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What’s in the water at waterbirth?

Waterbirth has been touted as an alternative form of pain relief in childbirth. Indeed, it is often recommended as the method of choice for pain relief in “natural” childbirth. It’s hardly natural, though. In fact, it is completely unnatural. No primates give birth in water, because primates initiate breathing almost immediately after birth and the entire notion of waterbirth was made up only 200 years ago. Not surprisingly, waterbirth appears to increase the risk of neonatal death.

Perinatal mortality and morbidity among babies delivered in water: surveillance study and postal survey was published in the BMJ in 1999. Out of 4,030 deliveries in water, 35 babies suffered serious problems and 3 subsequently died. It is unclear if any of the deaths can be attributed to delivery in water. However, of the 32 survivors who were admitted to the NICU, 13 had significant respiratory problems including pneumonia, meconium aspiration, water aspiration, and drowning. Other complications attributable to water birth include 5 babies who had significant hemorrhage due to snapped umbilical cord. In all, 18 babies had serious complications directly attributable to waterbirth. The risk of serious complications necessitating prolonged NICU admissions was 4.5/1000.

Hospitals in Ireland suspended the practice of waterbirth after a baby died from freshwater drowning after delivery in a waterbirth pool.

The most nonsensical aspect of waterbirth is that it puts the baby at risk for freshwater drowning. The second nonsensical aspect is that the baby is born into what is essentially toilet water, because the water in the pool is fecally contaminated. In Water birth and the risk of infection; Experience after 1500 water births, Thoeni et al. analyzed the water found in waterbirth pools both before and after birth. The water in a birth pool, conveniently heated to body temperature, the optimum temperature for bacterial growth, is a microbial paradise.

The authors were aware that the water system itself can harbor bacteria, given the report of at least two neonatal deaths from Legionella pneumonia, one that occurred in the hospital, and one that occurred at home. Therefore, they tested the water before anyone entered the pool. To their surprise and dismay, analysis of the water itself revealed that 12% of samples contained Legionella pneumophila, 11% Pseudomonas aeruginosa, 19% Enterococcus, 21% coliforms, and 10% Escherichia coli. Most of these organisms can and do cause infections in neonates. After installing a special water filter, and instituting more stringent pool cleaning procedures, contamination of the water by these bacteria was reduced, but not eliminated.

The analysis of the water after birth was shocking. Almost all 200 water samples were heavily contaminated with various infectious bacteria.

In the samples taken after the birth there was a high rate of contamination with coliforms (82%) and Escherichia coli (64%) with concentrations of up to 105cfu/100 ml; Pseudomonas aeruginosa, Staphylocooccus aureus, and yeasts were found less frequently.

The authors claim that the fecally contaminated water did not affect the rate of infection. However, the study is underpowered to reliably detect the impact of the contaminated water on the rate of infection. Second, the authors express their claim in a curious way:

Only 1.34% of children (10 of 741) born in water showed infectious signs such as tachypnea and suspect skin color compared with 3.40% (15 of 440) in the [control] group.

The relevant finding is not which babies displayed signs of infection. The relevant finding is which babies actually had infections. The authors neglect to share that information; we should keep in mind the possibility that there was a significant difference.

Waterbirth is praised for its ability to ease pain in some women, but is that really worth the risk of delivering a baby into fecally contaminated water teeming with harmful bacteria? What’s “natural” about that?

Posted in: Obstetrics & gynecology, Science and Medicine

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58 thoughts on “What’s in the water at waterbirth?

  1. dzelzkalns says:

    Is there a significant difference in the maternal mortality rate?

  2. storkdok says:

    Yuck! My first impression in residency when I heard about water births was, why would anyone want to deliver a baby into an E. Coli stew? Why take a chance? But most women have not worked in the NICU or seen how devastating these infections can be.

    I saw in the BMJ 1999 article several references to controlled trials to water births. I don’t have time right now to read them or look through the literature, the kids are awake! I’m wondering if there are any other studies/trials that have been done on this subject?

    *popping popcorn for the ensuing comments*

  3. Dawn says:

    I was never a fan of water births, and I saw a few. However, most of the birth center clients stayed in the water, or a shower, until late transition, then moved out of the water into another area and into a comfortable position to push.

    If a mother DID deliver in the tub, we brought the baby right to the surface to breathe. Usually, baby went right into mom’s arms, head above water, body below, then they both got out, were dried off and the delivery completed (cord cut, placenta delivered). I don’t think we ever had a placenta deliver in the tub.

    Anecdotally, (from my own records) none of the babies born in the water in the birth center developed any problems/infections within the first 6 weeks of life. The tub cleaning requirements were quite stringent, and I recall that the jets were cultured weekly. The cleaning regime must have been fairly effective as I can only recall one time that the tub was “off limits” while the jets were sterilized somehow (I don’t recall exactly what they did…but the whole birth center smelled of chlorine for DAYS!).

    Storkdok: I have worked in an NICU and seen neonatal infections. Yes, they are devastating. However, the most devastating infection I saw was the beta strep infection my best friend’s baby suffered. He was a very sick baby. Again, anecdotally from my records, within the first 6 weeks of life none of the babies born in the birth center were admitted to the hospital for an illness. We did have some admissions to NICU from other births, whose mothers were transports or direct admissions to labor and delivery as they were higher risk or PROM.

    And hey, will you pass the popcorn?

  4. storkdoc:

    “I’m wondering if there are any other studies/trials that have been done on this subject?”

    The American Academy of Pediatrics convened a study group to review the literature on waterbirth. The results of the review were published as Underwater Births, PEDIATRICS Vol. 115 No. 5 May 2005, pp. 1413-1414. They looked at 24 papers and case reports.

    According to the authors:

    “… Over the last several years, numerous case reports have associated underwater birth with respiratory distress, hyponatremia, infections, hypoxic ischemic encephalopathy, ruptured umbilical cords, seizures, tachycardia and fever (related to water temperature of the bath), and near drownings in newborns or fetuses.

    There is only 1 report of a randomized, controlled trial (RCT) of underwater birth, but it has not been published in a peer-reviewed journal. This study showed no difference in the number of neonates admitted to a NICU; however, it was not sufficiently powered to evaluate important morbidities (n = 120).

    There have been 6 published RCTs of water immersion during labor (only 1 in the United States). A Cochrane systematic review of 3 of theses trials, involving 988 mothers, found no benefits for pain relief, the course of labor, or perineal trauma for the mother and no differences in neonatal outcomes. The authors concluded that there were insufficient data to evaluate water immersion for labor.

    Subsequently, an RCT of water immersion for labor of 274 Australian women also found no benefit for pain relief, the length of labor, perineal trauma, or mode of delivery. However, more neonates born to mothers who labored underwater required oxygen or positive-pressure ventilation in the delivery room compared with the control group (49% vs 35%; relative risk: 1.41; 95% CI: 1.06–1.89).

    A Swedish study of 1237 women found no benefit or harm to mothers or infants after water immersion for labor.

    Cluett et al, from England, reported the results of an RCT in 99 women, comparing water immersion versus augmentation (amniotomy and oxytocin) for the subset of patients with labor dystocia. There were no differences between groups in the use of epidural analgesia, operative delivery, or duration of labor. Although women in the water-immersion group were less likely to receive augmentation than the routine-care group (relative risk: 0.74; 95% CI: 0.59–0.88) and generally had lower pain scores, 12% of neonates born to mothers who labored underwater were admitted to the NICU, compared with none in the augmentation group (P = .013).

    A second Cochrane systematic review of water immersion for labor by the same authors as the first was published recently. This report included the previously mentioned studies but also relied on unpublished data, personal communications, and data not published in peer-reviewed journals. The authors concluded that water immersion resulted in a reduction in the use of analgesia/anesthesia for mothers (odds ratio [OR]: 0.87; 95% CI: 0.71–0.99), but differences in vaginal operative deliveries (OR: 0.83; 95% CI: 0.66–1.05) and cesarean sections (OR: 1.33; 95% CI 0.92–1.91) did not reach statistical significance. The differences in the incidence of low Apgar scores (OR: 1.57; 95% CI: 0.63–4.01), admissions to a NICU (OR: 1.05; 95% CI: 0.68–1.61), and neonatal infections (OR: 2.01; 95% CI: 0.50–8.07) also did not reach statistical significance.

    The safety and efficacy of underwater birth for the newborn has not been established. There is no convincing evidence of benefit to the neonate but some concern for serious harm. Therefore, underwater birth should be considered an experimental procedure that should not be performed except within the context of an appropriately designed RCT after informed parental consent.”

  5. dzelzkalns:

    “Is there a significant difference in the maternal mortality rate?”

    No mother died in any studies. All of the studies are underpowered as to maternal mortality rates.

  6. storkdok says:

    Amy, thank you for the references!

    Call me a pessimist and a worry wort, but after infection and aspiration risks, I also worried about a shoulder dystocia. I have these really awful pictures in my mind about this occurring underwater. You’d have to get the patient out of the tub, and then…try to perform the maneuvers on the floor in a puddle of water? And how much room would there be for the necessary assistants? Or do you carry her over to the bed, or down the hall if the tub isn’t in the room? Not the most optimal place for resolving a shoulder dystocia, where seconds count.

  7. storkdoc:

    “I also worried about a shoulder dystocia.”

    There’s not enough data to be sure, but it does seem that the risk of shoulder dystocia is increased, although I’m not sure if it is true shoulder dystocia, or merely inability of the attendant to deliver because of lack of access.

    And, of course, shoulder dystocia, with its delay between delivery of the head and body would increase the risk of neonatal hypoxia, therefore possibly increasing the risk that the baby will aspirate a big gulp of water before being brought to the surface.

  8. caoimh says:

    Is there any evidence for some sort of vernix protection from the water?

    And on a lighter note, I wonder how this fits into the aquatic ape hypothesis!

  9. caoimh:

    “Is there any evidence for some sort of vernix protection from the water?”

    Vernix does contain antimicrobial peptides and, if vernix is present, that might afford protection against a skin infection. However, it would not be able to sterilize the water and would not prevent pneumonia after aspirating the water.

  10. Grinch says:

    caoimhon

    “And on a lighter note, I wonder how this fits into the aquatic ape hypothesis!”

    I think water birth is the final piece to the AAH puzzle! Oh, only if Sir Hardy were alive to see this breakthrough.

  11. I wonder how this fits into the aquatic ape hypothesis

    I believe it does. Leboyer cited such a hypothesis (that humans were formerly aquatic mammals) in his book, as I recall from reading it ca. 1970.

    This calls attention to the distinction between “water-birthing” in the Leboyer sense, in which it is claimed to be good for the baby to be born under water, and non-purposeful water births occurring in tubs that laboring women sit in to make laboring a little easier.

  12. Dacks says:

    “This calls attention to the distinction between “water-birthing” in the Leboyer sense, in which it is claimed to be good for the baby to be born under water, and non-purposeful water births occurring in tubs that laboring women sit in to make laboring a little easier.”

    Oh, yes. The (nationally known) medical center where I had my first child let me spend an hour in a hot tub during the middle part of labor. It was heavenly. They would not have allowed it if delivery were imminent.

  13. Plonit says:

    There’s not enough data to be sure, but it does seem that the risk of shoulder dystocia is increased, although I’m not sure if it is true shoulder dystocia, or merely inability of the attendant to deliver because of lack of access.

    +++++++++++++

    I think there is a level of misunderstanding here. The attendant does not typically “deliver” the baby in a waterbirth (i.e. it is a hands off procedure) – the baby is simply born into the water, then brought to the surface by the attendant (or mother).

    On what are you basing the suggestion that shoulder dystocia is more frequent at water births?

  14. rastan says:

    1) Water birth “is completely unnatural”

    -Fine

    2) Water birth “appears to increase the risk of neonatal death”

    -How does the BMJ reference support this? Isn’t one of the key findings that “the risk of perinatal mortality for babies delivered in water is similar to the risk for babies born by normal vaginal delivery to women at low risk of adverse outcome”? I may be misinterpreting the conclusion, but this doesn’t seem like the best reference to prove your point.

    3) Water birth “puts the baby at risk for freshwater drowning”

    -That makes sense, but how great is this risk? You reference the one drowning case in Ireland, and I see that there was one case in the BMJ study. Again, I’m not blown away by the evidence here.

    4) Water birth delivers “a baby into fecally contaminated water teeming with harmful bacteria”

    -Yuck indeed! Lots of scary sounding bacteria in the water samples from the study you referenced, but as you mentioned “the authors claim that the fecally contaminated water did not affect the rate of infection … the relevant finding is not which babies displayed signs of infection. The relevant finding is which babies actually had infections. The authors neglect to share that information; we should keep in mind the possibility that there was a significant difference.”

    So… the reference you chose to support your argument is one that a) doesn’t actually support your argument and b) you use to ask us to speculate along the lines of isn’t it interesting that there may have actually been many infections, but the authors may have left those results out?

  15. Grinch says:

    Dr. Tuteur,
    These studies or at least in the BMJ, were conducted in England. Is it possible that the results were also due to the less than tidy conditions in some hospitals?
    I wonder if those rates hold true in the United States?
    Also, there’s this Cochrane review,
    (http://www.ncbi.nlm.nih.gov/pubmed/19370552?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_SingleItemSupl.Pubmed_Discovery_RA&linkpos=2&log$=relatedreviews&logdbfrom=pubmed)
    Can you please comment on it?

    (Sorry don’t now how to use the “link” feature)

  16. “This calls attention to the distinction between “water-birthing” in the Leboyer sense, in which it is claimed to be good for the baby to be born under water, and non-purposeful water births occurring in tubs that laboring women sit in to make laboring a little easier.”

    Yes, most studies divided “waterbirths” into two groups, women who labored in water and women who actually gave birth in water. There are no risks associated with laboring in water. The risks are associated with birth in water.

  17. Plonit:

    “The attendant does not typically “deliver” the baby in a waterbirth (i.e. it is a hands off procedure) – the baby is simply born into the water, then brought to the surface by the attendant (or mother).”

    In a shoulder dystocia the baby isn’t “simply born.” An attendant is almost always required to rescue the baby.

  18. “there’s this Cochrane review”

    The American Academy of Pediatrics study group on waterbirth had this to say about the Cochrane review:

    “A second Cochrane systematic review of water immersion for labor by the same authors as the first was published recently. This report included the previously mentioned studies but also relied on unpublished data, personal communications, and data not published in peer-reviewed journals. The authors concluded that water immersion resulted in a reduction in the use of analgesia/anesthesia for mothers (odds ratio [OR]: 0.87; 95% CI: 0.71–0.99), but differences in vaginal operative deliveries (OR: 0.83; 95% CI: 0.66–1.05) and cesarean sections (OR: 1.33; 95% CI 0.92–1.91) did not reach statistical significance. The differences in the incidence of low Apgar scores (OR: 1.57; 95% CI: 0.63–4.01), admissions to a NICU (OR: 1.05; 95% CI: 0.68–1.61), and neonatal infections (OR: 2.01; 95% CI: 0.50–8.07) also did not reach statistical significance.”

  19. Plonit says:

    In a shoulder dystocia the baby isn’t “simply born.” An attendant is almost always required to rescue the baby

    +++++++++

    Quite right.

    I was trying to make sense of your comment that

    “There’s not enough data to be sure, but it does seem that the risk of shoulder dystocia is increased, although I’m not sure if it is true shoulder dystocia, or merely inability of the attendant to deliver because of lack of access.”

    It is not clear to me how “lack of access” in the context of waterbirth would increase the risk of shoulder dystocia occuring. Or did you mean that lack of access increases risks in the event that shoulder dystocia occurs?

    Also, can you explain your distinction between true and not-true shoulder dystocia, and how this relates to lack of access at delivery.

  20. Plonit:

    “Or did you mean that lack of access increases risks in the event that shoulder dystocia occurs?”

    The latter, since the issue wouldn’t even come up unless there was difficulty during the delivery.

    “Also, can you explain your distinction between true and not-true shoulder dystocia, and how this relates to lack of access at delivery.”

    A true shoulder dystocia occurs when the bisacromial (shoulder tip to shoulder tip) diameter of the fetus is larger than the antero-posterior diameter of the maternal pelvic inlet. As a practical matter, if the baby appears stuck but the attendant manages to deliver the baby with minimal difficulty, it wasn’t a shoulder dystocia.

    A true shoulder dystocia often can only be resolved when the baby’s clavicle is accidently or deliberately broken thereby reducing the bis-acromial diameter. Since the brachial plexus runs under the clavicle, resolving a shoulder dystocia may result in temporary or permanent damage of the nerves supplying the arm.

  21. Calli Arcale says:

    Frankly, water birth strikes me as one of the craziest of the “alternative” birth ideas. Babies drown in bathwater all the time; why would anyone think they’d be somehow protected from this during birth, the time when they’re most severely stressed and with the least knowledge of their environment? My second baby was born unconscious; she would surely have drowned. (Mind you, it was a c-section anyway.)

    Even forgiving the fact that it’s gotta be a very awkward setting for any kind of emergency intervention, and even ignoring the increased infection risk, the drowning risk should give anyone pause. It sure gives me pause, anyway.

    I’ve heard water-birth advocates claim that babies “instinctively” hold their breath when they emerge. Some use this as support of the “aquatic ape” hypothesis. (A whole ‘nother area of controversy, albeit among evolutionary biologists.) My question is this: is there really any scientific evidence behind that? I’m suspicious that there isn’t; to date, nobody’s shown me any evidence, and anecdotally, there are enough reported instances of accidental drownings that I’m dubious.

  22. Plonit says:

    A true shoulder dystocia occurs when the bisacromial (shoulder tip to shoulder tip) diameter of the fetus is larger than the antero-posterior diameter of the maternal pelvic inlet.

    ++++++++++++

    So, if the bisacromial diameter is not absolutely larger than the AP diameter, but nonetheless the shoulders are not born spontaneously due to the anterior shoulder being impacted under the pubis symphysis, that would not be a true shoulder dystocia in your book?

  23. Calli Arcale:

    “I’ve heard water-birth advocates claim that babies “instinctively” hold their breath when they emerge”

    Some waterbirth advocates embellish this claim even further by declaring that it is biological “diving reflex.”

    There is a diving reflex but it does not work the way that waterbirth advocates suppose. The scientific paper Respiratory responses to cold water immersion: neural pathways, interactions, and clinical consequences awake and asleep explains this reflex.

    1. The diving reflex exists to prevent drowning. Its primary purpose is to minimize oxygen consumption in pathological situations. It is elicited by the stress of attempting to avoid death, not as a typical response to normal phenomena.

    2. Breath holding is only one aspect of the diving reflex. The others are bradycardia and peripheral vasoconstriction; neither bradycardia (slow heart rate) or peripheral vasoconstriction (diminished blood flow to non-essential organs and tissues) are normal events. Bradycardia can be so profound as to lead to cardiac arrhythmias or cardiac arrest.

    3. The diving reflex is elicited by cold water, not by room temperature or warm water.

    The authors specifically address the physiologic response to waterbirth. Discussing the claims of waterbirth proponents, they write:

    “For some time it has been thought that the vagally mediated triad of responses to trigeminal nerve stimulation (apnea, bradycardia, and selective vasoconstriction) that constitute the oxygen conserving “diving response” provides protection against drowning for babies during underwater birth by conserving oxygen. However, it is known that the response in neonatal animals is markedly diminished in the presence of hypoxemia, as can occur with a difficult delivery, and recently underwater birth has been linked to neonatal distress and mortality as part of a near-drowning scenario with radiological evidence consistent with lung aspiration of birthing pool water. Thus it appears that the apnea associated with the diving response is insufficient in newborn babies to ensure that water is not inhaled during underwater delivery.”

  24. carrie says:

    I haven’t read through all the comments, but I wanted to ask: Is there increased risk for any issues when a woman uses water- either bath or shower or whatever- during labor but not for delivery?

    I know a hot shower/hot bath were both heavenly for me during a couple of my labors and my care provider (OB and CNM) never mentioned any risks to that. I am just curious if there really are risks as there are with birthing in the water.

    What about if your water has broke, does that change the risk?

  25. rastan says:

    “I’ve heard water-birth advocates claim that babies “instinctively” hold their breath when they emerge”

    “Some waterbirth advocates embellish this claim even further by declaring that it is biological “diving reflex.””

    ————————-

    Yeah, that diving reflex argument doesn’t really work for me either.

    Another reason I’ve heard water-birth advocates use is that the baby doesn’t actually take its first breath until the umbilical cord is cut (or until the cord “touches air”).

  26. Calli Arcale says:

    That’s about what I thought. Thank you.

    So the “diving reflex” is about as healthy and natural as the way the body shuts down organs to try to preserve brain function during asphixiation — i.e. there is such a response, but it’s only really helpful during life or death situations and it would be best not to need it in the first place.

  27. TsuDhoNimh says:

    As a microbiologist … EWWWWWW!!!!

    What were the colony counts? If the birthing tub were a beach or swimming pool, would it be closed by the health department?

  28. storkdok says:

    One of the requirements for laboring in the tub at our hospital was intact membranes. I don’t know if this is the norm at hospitals who offer laboring in water or not.

  29. Grinch says:

    far be it from me to step into a “birther” debate, but as I understand it, shoulder dystocia has to have certain elements such as
    1) It has to be a complicated (or abnormal, if you will) delivery which requires some sort of maneuver (“which additional maneuvers are required to deliver the fetus after normal gentle downward traction has failed”)
    2) The shoulder aspect would be, the shoulder not allowing proper passage through the vaginal canal, thereby requiring said additional maneuvers.
    2a) The impaction of the shoulder would, by logic, be due to, most likely an increase in the ratio of above stated diameter. In fact most are due to anterior vs posterior. The increase is most likely due to an increase in fetal birth weight, according to cochrane
    3) I’m so glad I don’t have to worry about this!

  30. provaxmom says:

    When I think of water birthing, I think of those ridiculous shows on Discovery that glamorize this. Sometimes I’m embarrassed for the women, because there they are…..putting it all out there, and often they have entire families circling the tub. It’s beyond bizarre to me. I’ve even seen one where the family did a home-water-birth with one of those portable whirlpools.

    And I can’t imagine, being in the final stages of L&D, and a baby getting stuck (shoulder dystocia or otherwise) and being able to climb out of a friggin bathtub! My first son required suction, and at that point of my labor (36+ hours) I wouldn’t want to climb out of a whirlpool and into a bed.

  31. TsuDohNimh:

    “What were the colony counts?”

    Up to 105 cfu/100 ml.

  32. Noadi says:

    Thank you for this article. I have a friend who told me she’d like to go with water birth when she has children. She’s obese and has heard it would make things more comfortable for her (sounds like laboring in water would be the way to go). Going to pass it along to her.

  33. nitpicking says:

    A true shoulder dystocia often can only be resolved when the baby’s clavicle is accidently or deliberately broken thereby reducing the bis-acromial diameter.

    I’m no doctor, but logically wouldn’t either episiotomy or a Caesarian section also resolve this situation? Or is it too late to do either by the time shoulder dystocia is obvious?

  34. magra178 says:

    I had thoughts similar to carrie’s: what about laboring in water? some women wish to do this, and some hospitals allow it (but not water births). I remember being told no baths if your water broke, but before that it could help in labor (while at home). So my question would be, is laboring in water safe if your water is broken?

  35. Plonit says:

    I’m no doctor, but logically wouldn’t either episiotomy or a Caesarian section also resolve this situation? Or is it too late to do either by the time shoulder dystocia is obvious?

    +++++++++++

    There is a procedure called the Zavanelli maneouvre (pushing the head back in and then performing caesarean section), but it very very rarely used and only used when other maneouvres have failed. Shoulder dystocia is a bony problem, so episiotomy won’t release the shoulder – however it is often cut to allow access for internal maneouvres.

    Dr Amy’s definition of true shoulder dystocia is much narrower than that which is generally used in the literature and by practitioners. A more conventional definition would be (following Resnick, RCOG etc) “additional maneouvers are required to deliver the fetus after normal gentle downward traction has failed.” This is why I wondered if the routine absence of ‘gentle downward traction’ in waterbirth was at issue.

    Using this conventional definition of shoulder dystocia the rate usually quoted is 0.6% (see ->

    http://www.rcog.org.uk/files/rcog-corp/uploaded-files/GT42ShoulderDystocia2005.pdf )

    Thöni et al, 2007, report a rate of 0.16% in a series of 1825 waterbirths over nine years. Now that lower incidence could be selection bias (although if obese women are being advised to give birth in water, I wouldn’t be so sure about that!) or it could be the result of a plausible biological mechanism – that the pelvis is more mobile in water than when the sacrum is fixed by the woman’s weight (as in dorsal and semi-recumbent positions).

    Is there any data that supports the assertion that waterbirth increases the risk of shoulder dystocia?

  36. Plonit:

    “Thöni et al, 2007, report a rate of 0.16% in a series of 1825 waterbirths over nine years.”

    No, that’s not what they found.

    Although the title of the paper is “Giving birth in the water: experience after 1,825 water deliveries. Retrospective descriptive comparison of water birth and traditional delivery methods” that’s not really what the study is about. According to the authors:

    “We compared 830 primipara deliveries in water with 424 primipara deliveries in the traditional bed and 136 on the delivery stool. We also evaluated the duration of labour, arterial cord blood pH and base excess in the primiparae, and perineal trauma, shoulder dystocia and deliveries after preceding caesarean section as well as rates of neonatal infection in all the 1,825 water births.”

    There were 3 shoulder dystocias among 830 deliveries for a rate of 0.36%.

    “that the pelvis is more mobile in water than when the sacrum is fixed by the woman’s weight”

    What evidence is there for that claim?

    After all, waterbirth has no impact on c-sections or operative vaginal deliveries suggesting that it has no impact on pelvic dimensions.

  37. Réka Morvay says:

    Some questions:

    1. How long did they wait after the birth until they sampled the water? Time lapsed between the birth of the baby and taking the sample (as well as variations in water temperature) could seriously affect colony counts, couldn’t it?

    2. What kind of infectious bacteria could be grown from samples taken from a woman’s vagina and perineum if sampled right after birth?

    3. When will we see a balanced discussion on the risks and benefits of hospital-based obstetric procedures? I appreciate Dr. Amy’s posts calling attention to medical literature on natural birth practices, but where is the same dissecting common hospital procedures and the misconceptions surrounding those, such as the high rate of inductions and the resulting rate of iatrogenic prematurity? Dr. Amy, your credibility would be greatly enhanced if you discussed problems on both sides of the natural vs. medicalized debate.

  38. Reka Morvay:

    “What kind of infectious bacteria could be grown from samples taken from a woman’s vagina and perineum if sampled right after birth?”

    The same bacteria. That’s where the bacteria come from. The difference is that we don’t expect the baby to inhale a big lungful of flora from the perineum.

    “where is the same dissecting common hospital procedures and the misconceptions surrounding those, such as the high rate of inductions and the resulting rate of iatrogenic prematurity? Dr. Amy, your credibility would be greatly enhanced if you discussed problems on both sides of the natural vs. medicalized debate.”

    I have a long list of issues like those that I plan to address. I predict that you may be surprised to find that much of what you have heard about these issues is not substantiated by the scientific evidence.

    For example, it is true that increasing the rate of inductions has increased the rate of iatrogenic prematurity. But it is also true that in the same time period stillbirths have dropped by 29%. It seems that the benefits outweigh the risks.

    Much of the band press about hospital interventions is simply not warranted. That’s why it’s always important to review the scientific literature, and review all of it. The findings are often the direct opposite of the conventional wisdom.

  39. Basiorana says:

    I can’t imagine water birth would affect maternal mortality that much. If a woman had a big cut or had a bad gastroentestinal infection and the fecal matter got into her birth canal, maybe. But I imagine if you had diarrhea or vomiting you probably wouldn’t have a water birth anyway. Besides, any infection would likely be easily treatable in a first-world nation where these births take place, with simple antibiotics– the risk isn’t as big as it would be with a baby.

    “I’m no doctor, but logically wouldn’t either episiotomy or a Caesarian section also resolve this situation?”

    My mom had an epi to birth my sister’s shoulders. My sister was too far down the birth canal for a C-section, though, by the time dystocia can be diagnosed their head is out or partly out. It wasn’t really dystocia, though, because dystocia implies the shoulder is caught on the pubic symphysis– the cartilage.

    What I like about water birth is some women will sit there, cuddling the baby, in the water until the placenta is out. And they talk about how it’s not gross because the midwife uses a fish net to scoop out the poop. Just…. ick.

  40. Calli Arcale says:

    Dr. Amy, your credibility would be greatly enhanced if you discussed problems on both sides of the natural vs. medicalized debate.

    My two cents:

    There shouldn’t be a “natural” versus “medicalized” debate. It’s a false dichotomy. The emphasis shouldn’t be on which is better but on which particular procedures/interventions produce what results. This particular post is focusing on waterbirth, so I don’t think it’s surprising that it doesn’t discuss induced labor. (I think induced labor would contraindicate waterbirth, since you have to be attached to an IV drip. I know because my first was induced at 42 weeks.)

    This is offtopic, but as far as “iatrogenic prematurity”, whether it’s a good thing or a bad thing has to look at what would have happened otherwise, and the reasons why it is done. Certainly prematurity is not a good thing. It is best if the baby “cooks” the full duration. But sometimes it is better than the alternative. In her response to you, Dr Tuteur alludes to the rate of stillbirths. Are these babies being induced because of indications of distress? If so, it may not be a bad thing after all. I, too, would be very interested to see a post on that topic. It’s a big one. Of course, there are *lots* of topics I’d like to see, so I would not be disappointed if she doesn’t do that one soon. ;-)

  41. Deetee says:

    Forgive me if this has been covered already.

    Regarding the fecal contamination, so what?
    It is accepted that within a few hours of birth neonates have been colonised by the mother’s gut flora. In fact it is something thought to be quite important for the baby’s health.
    How does being delivered into a diluted broth of the bacteria differ from being forced through a contaminated birth canal anyway, with its undoubtedly higher bacterial counts (judged by CFUs)?

  42. Deetee:

    “How does being delivered into a diluted broth of the bacteria differ from being forced through a contaminated birth canal anyway, with its undoubtedly higher bacterial counts”

    If the baby is delivered underwater, it could aspirate a large amount of contaminated water with its first breath leading to pneumonia and potentially death.

    Babies should not be born underwater. There is no benefit to the baby, only risk, including the risk of fresh water drowning and aspirating fecally contaminated water.

  43. Basiorana says:

    Yeah… I always figured the mother’s gut flora was supposed to colonize the baby’s gut, not their lungs.

  44. rastan says:

    So if we put aside the distracting “natural” definitions and bacteria discussions, it seems that the bottom line is: babys born underwater are at risk of taking their first breath underwater, and that may lead to drowning, aspirating fecally contaminated water, etc.

    That sounds plausible enough, but as I asked in my previous comment: how great is this risk? There is the one case of drowning in the BMJ study, but didn’t the study also declare that “no deaths were directly attributable to delivery in water” and “perinatal mortality is not substantially higher among babies delivered in water than among those born to low risk women who delivered conventionally”?

    Maybe I’d be better able to understand the risk if you could explain what factors contribute to a baby taking its first breath. As I mentioned in a different previous comment, I’ve heard the “the baby doesn’t take its first breath until after the umbilical cord is cut or ‘touches air’” explanation, but I’m curious whether there is any truth to that or not.

  45. rastan:

    “I’ve heard the “the baby doesn’t take its first breath until after the umbilical cord is cut or ‘touches air’” explanation, but I’m curious whether there is any truth to that or not.”

    No, there’s no truth to that. The baby can take its first breath at any time, even before the body is fully born.

    “how great is this risk?”

    There are a number of case reports in the literature about drowning and pneumonia from waterbirth.

    The key point is that proponents deny that there is any risk, since they lack understanding of newborn physiology. Delivering in water is the equivalent of delivering into the toilet and then lifting the baby out. Why would anyone want to take that risk?

  46. TsuDhoNimh says:

    rastan … In all, 18 babies had serious complications directly attributable to waterbirth. The risk of serious complications necessitating prolonged NICU admissions was 4.5/1000.

    When delivery in a water bath is 100% optional, and complications serious enough to put the baby in NICU (Neonatal ICU) happened at a rate of 4.5 of every 1,000 births, over a series of 4,000+ births (quite a large sample) … it’s medically a no-brainer.

    Maybe no babies died, but admission to NICU means the complications were, uh, complicated. It means the baby was sick enough to need some complicated, high-tech support.

    There are no medical reasons for a water birth – there are lower risk ways to control pain and relax muscles.

  47. rastan says:

    I think it would really help answer my “how great is this risk” question if that 4.5/1000 NICU rate could be put into perspective. What is a typical NICU rate for low risk, conventional births? If it is closer to 0, then I can follow the “no-brainer” logic. However, the main cause of my confusion is the BMJ study. They observed a 4.5/1000 NICU rate with water births, and then they state:

    “UK reports of mortality and special care admission rates for babies of women considered to be at low risk of complications during delivery who delivered conventionally ranged from 0.8/1000 (0.2 to 4.2) to 4.6/1000 (0.1 to 25) live births and from 9.2 (1.1 to 33) to 64/1000 (58 to 70) live births respectively.”

    They make it sound like the risks of underwater birth are not very different from low risk conventional births. Even in their conclusion, they specifically state “perinatal mortality is not substantially higher among babies delivered in water than among those born to low risk women who delivered conventionally.”

  48. “I think it would really help answer my “how great is this risk” question if that 4.5/1000 NICU rate could be put into perspective.”

    There are no large scale studies that will answer your question.

    The risks of underwater birth, by Pinette et al. (AJOG, Volume 190, Issue 5, 2004) summarizes what we know:

    “A surveillance study by Gilbert and Tookey[the BMJ study I referenced above] suggests that the relative risk of underwater birth in terms of death and admission to a neonatal intensive care unit is small. Gilbert and Tookey report 15 cases of respiratory tract problems that are attributed directly to water aspiration. Grade 2 to 3 ischemic encephalopathy was reported in 5 cases. The surveillance study also reported 5 cases of cord avulsion (1 in 270 water births), which was thought to be the result of rapid cord traction as the infant was brought to the surface. One of the 5 neonates required a transfusion. In this report, the perinatal mortality rate was 1.2 per 1000 births, as compared with 0.8 per 1000 births in a similar low-risk group. The authors of the study correctly point out that the perinatal mortality rate for infants who are delivered in water was not increased statistically. The confidence limits, however, were wide (0.4-2.9). In a separate letter to the editor, Gilbert stated that the additional risk that is attributable to underwater births has not yet been determined because of insufficient data. Gilbert stated that water birth “undoubtedly” causes serious adverse outcomes and that the “population-based studies cannot exclude a clinically important increased or decreased risk in mortality, much less morbidity.”

    Cases of near-drowning that have been reported with water births raise the issue of impaired fetal lung fluid removal. Bypassing normal physiologic condition could also lead to increased transient tachypnea. The retention of water as a drowning experience with water birth has been reported. Rosser reports 2 home births with likely drowning, which resulted in the death of 1 neonate and severe brain damage in a second neonate who was left under water for 25 minutes. The newborn infant death occurred while under the care of experienced midwives. The neonate was observed to make respiratory efforts on its way to the surface. The infant was born in distress and was not able to be resuscitated, because it was impossible to ventilate presumably because of the water-logged lungs that were identified clearly at autopsy. Recently, Nguyen et al reported a series of 4 cases of near-drowning with moderate-to-severe respiratory distress after underwater deliveries. All 4 cases demonstrated classic radiographic features that are consistent with fresh water drowning. Although decidedly uncommon, these case reports of respiratory complication that was associated with water birth are of concern.

    Hyponatremia at birth as a function of swallowing free water in the tub seems likely to be a result of a water birth. In cases of fresh water drowning, fluid can be absorbed quickly through the lungs into the circulation, which results in intravascular dilution and fluid overload. As a result, it has been suggested that salt should be added to the pool to make the solution more isotonic, which most probably would prevent dilution and hyponatremia.

    Hypoxic ischemic encephalopathy has been reported in neonates who were delivered underwater. Rosevear et al reported a case of asphyxia and a case of encephalopathy in 2 women who labored 7 hours in the birthing pool. Both left the pool a few minutes before delivery and technically would not have been considered an underwater birth. They suggest that hyperthermia possibly played a role in the diversion of maternal circulation to the skin, to reduce maternal core temperature. Decreased utero placental perfusion combined with increased fetal metabolic rate as the result of hyperthermia may worsen fetal oxygenation. No obvious cause of the in utero hypoxia was apparent. Table I includes several other cases of hypoxic ischemic encephalopathy, which can be seen in normal deliveries. However, 5 of the 8 deliveries were associated with other complications that most likely were attributed to water birth, such as cord avulsions and drowning…

    There are a number of reports of neonatal infections that are thought to be potentially due to underwater births. In particular, neonatal pseudomonas sepsis has been identified in mothers who undergo water birth, with the identical strain being isolated within the tub in some cases. The culturing of pseudomonas from both the tub and the neonate suggests a potential link. Reports of very unusual waterborne bacteria, such as legionella, that caused neonatal infections that were discovered after water birth likewise suggest the birthing tub as a potential source. These water-borne infections, when acquired in a hospital setting, may be at an increased risk for more virulent and more difficult to treat organisms…

    There is a lack of evidence to suggest a benefit of underwater birth and mounting evidence to suggest occasional poor outcomes that might be attributable to the procedure. The reports of hyponatremic seizures, drowning, waterborne infections, the potential of delivering an unexpectedly compromised fetus in a difficult to resuscitate environment, potential for fetal hemorrhage from snapped umbilical cords, risk of delayed delivery in cases of fetal asphyxia, risk of shoulder dystocia, and injury to health care workers moving patients in and out of the tub are complications that may be possibly attributed to underwater births.

    Some proponents of water birth make a case that the perceived unproven benefit of water birth in terms of labor duration, pain control, and perineal tears outweighs the small potential risk. Women who contemplate water birth, as all women about to give birth, regard the well-being of their newborn child to be the most important consideration. To make an informed decision, these women must know the likelihood of a significant adverse outcome that is attributable to water birth. However, the additional attributable risk of water birth is uncertain because of a lack of data. Although Gilbert and Tookey surveillance study suggests that delivery in water does not increase perinatal complications substantially overall, the additional attributable risk for specific harms (such as water aspiration, drowning and aspiration, hyponatremia, neonatal infections and even death) are not known. The confidence limits on mortality rates alone was wide (0.4-2.9 per 1000 births). We would agree with the conclusions of the Cochrane database that there is a need for a large collaborative, randomized controlled study of underwater birth to determine the possible harmful effects on the fetus and/or newborn infant. To make an informed decision, women who are considering water birth should be given balanced information that includes the potential harms of the procedure.”

  49. Dacks says:

    Amy,
    Thanks for that long quote. It really makes clear the numerous risks of underwater birth. (shudder!)

  50. rastan says:

    “There are no large scale studies that will answer your question.”

    I’m sorry to hear that. It seems that the main challenge in arguing against alternative birthing procedures (and alternative medicine in general) is presenting a clear, evidence-based argument that can be easily understood by the general public. Something along the lines of “vaccines do not cause autism”, “there is no difference between real acupuncture and fake acupuncture”, or “homeopathy is water”.

    It certainly would help the “water birth is riskier than conventional birth” argument if there was either a conventional birth NICU rate or an “acceptable” NICU rate for comparison. Looking back at your previous C-section post, I suppose I could conservatively use your “acceptable” MMR of 15/100,000 (as a quick “back of the envelope” calculation; I realize that an acceptable mortality rate is likely lower than an acceptable rate of complications). That gives an “acceptable” rate of 0.015%, which is 30 times lower than the 0.45% (4.5/1000) NICU rate of water birth from the BMJ study.

    Although, now I’m realizing that it may be difficult for most people to see why having 99.985% complication-free births is acceptable and having 99.550% complication-free births is too risky.

    Hmm, I guess I can’t blame you for using the more emotionally-charged “water birth is not natural!” and “It’s like giving birth in a toilet!” arguments.

  51. rastan:

    “It seems that the main challenge in arguing against alternative birthing procedures (and alternative medicine in general) is presenting a clear, evidence-based argument that can be easily understood by the general public.”

    The main indictment of alternative birthing practices is that there is no scientific evidence to support them. The sad fact is that the claims about them and the empirical claims underlying them were simply fabricated from whole cloth.

    Waterbirth is a paradigmatic example, but there are many others. It is entirely “unnatural.” Neither its benefits or risks were ever examined before it was instituted. The claim that babies won’t attempt to breathe underwater was made up, contradicting everything we know about fetal physiology and the diving reflex.

    Almost every practice exclusive to midwifery (as opposed to copied from obstetrics) and promoted by “natural” childbirth has never been tested or has been tested by others and shown to be ineffective or dangerous.

    Lamaze and other “natural” childbirth advocacy groups like to claim that obstetricians ignore the scientific evidence. That’s just another claim they made up. Obstetrics is based on scientific evidence, evidence that is imperfect and changes, but evidence nonetheless. “Natural” childbirth has no basis in science, from its inception to this very day.

  52. rastan says:

    “The main indictment of [water births] is that there is no scientific evidence to support them.”

    Doesn’t the evidence from the BMJ study suggest that water births were “successful” (i.e. without complications) in 4014 of 4032 cases?

    ————————————————————————-

    “The claim that babies won’t attempt to breathe underwater was made up”

    Origin aside, isn’t there some truth to that claim (again, pointing to 99.550% complication-free water births from the BMJ study)?

  53. “Doesn’t the evidence from the BMJ study suggest that water births were “successful” (i.e. without complications) in 4014 of 4032 cases?”

    That doesn’t make it safe. There should be no complications attributable to waterbirth since it is supposed to have no risks and only benefits.

    “Origin aside, isn’t there some truth to that claim (again, pointing to 99.550% complication-free water births from the BMJ study)?”

    No.

    First of all 99.55% doesn’t mean it is safe; it’s means that it is dangerous.

    For comparison, consider: If 99.55% airline flights didn’t crash. there would have been 2,397 plane crashes in 2008. Instead there were 28.

  54. StatlerWaldorf says:

    Again Amy, what is your complete definition of natural childbirth if you are going to claim, ““Natural” childbirth has no basis in science, from its inception to this very day.”

    Do the research studies highlight problems in how the waterbirths were conducted that lead to those particular cases of complications. Could there be protocols for waterbirths that reduce the risk of complications? Wouldn’t you agree that more research is necessary?

    Since so few women are homebirthing and waterbirthing anyway, don’t you think it would be productive to create articles that deal with more widely important controversies in obstetrics, like continuous vs intermittent fetal monitoring, birth position, episiotomies, and induction of labour to name a few. The vast majority of women are birthing in hospitals where these are pressing issues, and many women who are attracted to homebirth because of these issues would benefit from the discussion as well.

    Finally, is the only measure of this scientific debate on birth practices the neonatal mortality rate? Are there perhaps other measures to consider as well? What about cultural, sociological, psychological, ethical, legal aspects…

  55. joline says:

    What kind of water was used in the study?
    IE: clorinated tap water, such as might be used for waterbirths here in the US?

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