The Butterfly and the Caesarean

A man found a cocoon of a butterfly. A a small opening appeared, and he watched the butterfly struggle to force its body through that little hole.

It seemed to stop making any progress. It appeared as if it had gotten as far as it could and could go no farther.

The man helped the butterfly; he took scissors and snipped off the remaining bit of the cocoon. The butterfly then emerged easily. But it had a swollen body and small, shriveled wings.

The man expected that, at any moment, the wings would enlarge and expand to be able to support the body, which would contract in time.

It didn't. The butterfly spent the rest of its life crawling around with a swollen body and shriveled wings. It never was able to fly.

What the man did not understand was that the restricting cocoon and the struggle required for the butterfly to to get through the tiny opening were God's way of forcing fluid from the body of the butterfly into its wings so it would be ready for flight once it achieved freedom from the cocoon.

So, as I wrote a couple of posts back, I said I would take a look at the study summarized under the Medpage Today headline “Normal Vaginal Births Cause Infant Brain Hemorrhages.” I have pasted in the study’s abstract and the URL for it from PubMed for those of you not familiar with the study’s details.

Intracranial hemorrhage in asymptomatic neonates: prevalence on MR images and relationship to obstetric and neonatal risk factors.

Looney CB, Smith JK, Merck LH, Wolfe HM, Chescheir NC, Hamer RM, Gilmore JH.

Department of Psychiatry, CB No. 7160, 7025A Neurosciences Hospital, University of North Carolina School of Medicine, Chapel Hill, NC 27599-7160, USA.

PURPOSE: To retrospectively evaluate the prevalence of neonatal intracranial hemorrhage (ICH) and its relationship to obstetric and neonatal risk factors. MATERIALS AND METHODS: Pregnant women were recruited for a prospective study of neonatal brain development; the study was approved by the institutional review board and complied with HIPAA regulations. After informed consent was obtained from a parent, neonates were imaged with 3.0-T magnetic resonance (MR) imaging without sedation. The images were reviewed by a neuroradiologist with 12 years of experience for the presence of ICH. Medical records were prospectively and retrospectively reviewed for selected risk factors, which included method of delivery, duration of labor, and evidence of maternal or neonatal birth trauma. Risk factors were assessed for relationship to ICH by using Fisher exact test statistics. RESULTS: Ninety-seven neonates (mean age at MR imaging, 20.8 days +/- 6.9 [standard deviation]) underwent MR imaging between the ages of 1 and 5 weeks. Eighty-eight (44 male and 44 female) neonates (65 with vaginal delivery and 23 with cesarean delivery) completed the MR imaging evaluation. Seventeen neonates with ICHs (16 subdural, two subarachnoid, and six parenchymal hemorrhages) were identified. Seven infants had two or more types of hemorrhages. All neonates with ICH were delivered vaginally, with a prevalence of 26% in vaginal births. ICH was significantly associated with vaginal birth (P < .005) but not with prolonged duration of labor or with traumatic or assisted vaginal birth. CONCLUSION: Asymptomatic ICH following vaginal birth in full-term neonates appears to be common, with a prevalence of 26% in this study. (c) RSNA, 2007.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?CMD=Display&DB=pubmed

Here are the problems and weaknesses that jumped out at me:

• The study reports that instrumental vaginal delivery was not associated with these “small bleeds,” as they are described in the article (don't you love them using the word "hemorrhage" in the title and in the take-home message to be given to parents?), that caused no symptoms; however, studies consistently find an association between instrumental vaginal delivery and larger, symptomatic bleeds. With only 65 vaginal births, of which 13 were instrumental vaginal deliveries, the study lacks the statistical power to detect a difference, so this conclusion is misleading.
• These births were not “normal” by Lamaze International’s standards. Twenty out of every 100 women having a vaginal birth in this population had an instrumental delivery (13 out of 65). Fourteen out of every 100 babies (9 out of 65, assuming all trauma occurred during vaginal delivery) experienced delivery trauma, defined as “cephalohematoma [a fluid-filled swelling under the scalp], scalp laceration [cuts], or bruising associated with the use of forceps.” Given this rate of vaginal instrumental delivery and delivery trauma (can you imagine these stats in a home birth practice or at a free-standing birth center even including transfers to hospital?), it’s a safe bet that pushing position and technique were also not physiologic. “But,” as they say on the late night commercials, “there’s still more.” Investigators note that most bleeds were at the base of the skull. As a retired doula, I can tell you that conventional obstetricians often don’t just “catch” babies. The head emerges, and then they tug, and maneuver, and twist the baby’s head to “deliver” the shoulders, as if the shoulders wouldn’t come out on their own. It’s also a safe bet that a high proportion of the women were given drugs to start or intensify labor. Overly strong contractions in second stage might have a harmful effect too. In summary, like the accusations that vaginal birth weakens the pelvic floor, we don’t actually know to what degree these bleeds are inherent to vaginal birth and to what degree they are iatrogenic (caused by doctors) injuries. It would be interesting to do a study comparing MRIs of babies whose mothers pushed in positions other than on their backs, who pushed and breathed according to their inner urges, and who birthed their babies truly spontaneously with babies whose mothers had typical obstetric management.
• Amy Romano, my boss at Lamaze International, and author of Lamaze’s quarterly Research Roundup, points out another confounding factor: Babies with bleeds had the MRI at a mean of a week earlier than babies who didn’t have bleeds. Why is this important? The investigators note that they excluded infants older than 5 wks from the study because other studies had found that “all hemorrhages identified at birth had resolved by that age.” In other words, a week could make a big difference as to whether a bleed was found or not. If women having cesarean surgery tended to have their babies scanned later, this could explain some of the difference between groups.
• Even if vaginal birth is inherently associated with small bleeds, what the radiologists measured is a surrogate outcome, that is, an outcome believed to be in the causal pathway to a clinical outcome but not one itself. Surrogate outcomes often turn out to be misleading. For example, hormone replacement therapy improves blood lipid profiles in menopausal women but doesn't reduce heart attacks. It is likely that head molding can cause a bit of bleeding at the suture lines even when care during labor is optimal--which it certainly was not here--but it would be faulty logic to assume that this is anything but innocuous. Remember that no adverse effects were seen in these babies. In point of fact, we have no evidence that the liberal use of cesarean surgery improves neurologic outcomes compared with spontaneous labor and spontaneous vaginal birth. On the contrary, we have ample evidence of its potential harms for babies, not to mention women, in both the current and future pregnancies.

It is, to put it mildly, disingenuous to recommend telling parents that vaginal birth causes “brain hemorrhage” while cesareans do not, and then add “but we think it’s probably nothing to worry about.” There is, however, a real take-home message that was noted by the investigators but didn’t make it into the news or the study abstract: Should a baby in the first weeks of life undergo neurologic imaging, finding a bit of blood under the skull does not necessarily mean the baby has been physically abused—at least, considering the number of instrumental deliveries and the amount of delivery trauma reported in this study, not by the baby’s family.

-- Henci

I'm pleased to know that you find my post helpful. Deconstructing these studies is my idea of a good time. To be honest, I don't spend time surfing other sites. You could certainly link to my post, though, or copy and paste into a post on the BabyCenter.com site. And while you were at it, I can't say enough good things about the Lamaze Giving Birth with Confidence blog at http://birthwithconfidence.blogs.lamaze.org/. You might give them a plug. 

-- Henci

I just posted some talking points about the “brain bleed” study under "Resources for Educators" here.

Hi,

my baby was born 4 weeks ago, by a normal birth (vaginal) and yes, the doctor adviced us he has two cephalohematomes. They are two swollen areas filled with blood and liquid, they measure 3/4" each, but then again the same doctor (he's the pediatric doctor of the birth center in wich my baby was born) specified us that this hemorrhages are "normal" (at least in this center) and they should be disappeared by 6 months or so...

A cephalohematoma is a fancy word for a type of bruise, that is, bleeding under the scalp and outside the skull. It will take a while for the bruise to go away, as it does for any bruise, but they are not a problem. The study discussed in this thread is about bleeding inside the skull, which in the wrong place and in sufficient quantity--although not in the study under discussion--can be serious.

-- Henci

I had posted a question in another section about this same thing but I think you may be able to answer it from this blog. My son was born with what the doctors called two "epidural hematomas". They were very large and stayed on his head until his was about 4 months old. It has always scared me thinking that the blood could have gone under the skull instead of on top. I am now pregnant and due in Jan and am afraid of this happening again and maybe worse. I was wondering if there are some type of positions or something else I could do to try and prevent this from happening again? It was a very long and drawn out labor with my first and it seemed as though he was just stuck for a really long time.

Thank you.

Unfortunately, I have been in a car accident and am recovering from knee surgery. I will not be able to respond to your question at this time. Apologies.

~ Henci