Examining Home and Birth Center Birth Safety in Various Risk Populations

Last month, UPI published an article on the Midwives Alliance of North America (MANA) data analysis, "Perspectives on risk: Assessment of risk profiles and outcomes among women planning community birth in the United States." As you can tell by the title, the study evaluates the effects of various maternal factors on outcomes among people planning birth at home or a freestanding birth center (community birth) at labor onset. In the UPI article, one of the study's authors positions the study as assisting people in weighing the potential benefits vs. harms in their individual case, and as you would predict, the two obstetricians interviewed for the article pronounce that birth outside of a hospital is always more dangerous than birth in one. Granted, they acknowledge that women have the right to choose community birth, but the implication is that they are irresponsible to do so. Let's see what the study found, together with additional information from a webinar presentation by Melissa Cheyney, one of its authors, and consider the implications.

Community Birth Risks?

The MANA dataset is some of the best information we've got on community births because it is large enough (47,394 people planning community birth at onset of labor in this study) to measure differences in rare outcomes; because, unlike generic hospital or government data sources used by obstetric researchers, data collection was specifically designed for studying community birth care and outcomes; and because it is prospective, that is, midwives enter their clients into the database when they enroll in care, and they are tracked thereafter, which means midwives can't cherry pick which cases to submit.

As the UPI article states, after adjusting for correlating factors, a first labor after cesarean increased the risk of newborn death during labor and in the 28 days after birth 10-fold (10 vs. 1 baby per 1000) compared with women with prior births and no prior cesarean, and labor with a breech increased the risk 8-fold (17 vs. 2 per 1000) compared with labor with a head-down baby. However, these comparisons are with women in the population planning community birth who don't have the risk factor, not with women with the same risk factors planning hospital births. This means they don't tell us how much-or even whether-births with these factors would have turned out differently had they been planned hospital births, although it is likely that at least some of them would. Furthermore, the database didn't allow analysts to determine which women were immediately transferred to hospital care when first seen in labor by their midwife, which further clouds the picture if the point is to determine the degree to which outcomes would be improved by planned hospital birth.

There's still more: Cheyney noted in the webinar that planned out-of-hospital VBAC was more common in regions where access to hospital VBAC was limited. In other words, women choose community birth because contrary to every patient's right to refuse surgery, pregnant ones not excepted, they can't get a vaginal birth in the hospital. Community birth is their only option if they wish to avoid the hazards of accumulating cesarean surgeries to themselves, their babies, and future pregnancies. Ditto for breech. So, if women are choosing a riskier option, whose fault is that?

We're not done yet. The discussion that followed the webinar considered the role played by the lack of an integrated system. Where direct-entry midwives are illegal or hospital staff is antagonistic to women transferring in from homes or birth centers, transfer delay in the face of concerning symptoms is more likely. In support of that argument, Cheyney observed that midwives are licensed in both Oregon and Washington State, but Washington State, which has integrated community birth into the system, has better outcomes than Oregon, which hasn't. Again, if transfer is being delayed because of fear of legal repercussions, or because women transferring in are treated with hostility, or because care after transfer isn't timely because the hospital won't work with out-of-hospital midwives to handle transfers smoothly and expeditiously, whose fault is the resultant poor outcome?

Hospital Delivery Hazards?

The UPI article also points out that the babies of older women, high BMI women, and women who have already had a VBAC are not at excess risk for death. Neither, according to the study, are the babies of women with gestational diabetes or, according to the webinar presentation, babies before 42 weeks' gestation. This means that the conventional medical management belief that age, weight, prior cesarean, gestational diabetes, and pregnancy past 41 weeks inherently confer increased risk is wrong. Babies of otherwise healthy women aren't at increased risk simply because of their mother's age, weight, mild glucose intolerance, or because the pregnancy has reached 41 completed weeks. Likewise, women who have had a prior VBAC aren't in the same risk category as women who haven't. And that means that management based on the belief that they are exposes women and their babies unnecessarily to the harms of tests, restrictions, and procedures to their detriment.

There's still more here too. Not mentioned in the UPI article is the other side of the coin: the benefits of planning community birth. The MANA dataset sets the standard by which medical-model management is tried and found wanting. Planning birth at home or in a freestanding birth center greatly reduces the odds of cesarean. The cesarean rate in 1^st-time mothers was 11% whereas it is currently 26% nationally in U.S. low-risk 1st-time mothers (NTSV nullip, full-term, singleton, head-down baby). (Martin 2017). The VBAC rate in women with no prior VBAC was 78%. The rate in gestationally diabetic women was 8%; it was 6% in women older than 35; and it was 6% and 7% in high BMI (25-34) and very high BMI (35 or more) women, respectively. Cesarean surgery, as noted, has serious potential consequences, including one more fetal demise per 1000 in late pregnancy of unknown cause in the next pregnancy (Moraitis 2015)

The Take-Away

What are we to make of all this? Unless women can be assured of optimal care (the least use of medical intervention that produces the best outcomes given the woman's individual case) in the hospital, if they are healthy, they are better off planning community birth with a qualified midwife because of their greatly reduced risk of exposure to medical interventions they neither need nor benefit from. Women may still be better off planning community birth even with moderate risk factors, especially if they live reasonably close to a hospital and their midwives have a transfer protocol in place or at least a cordial relationship with hospital staff. If none of the above is true, women are forced into a painful dilemma whose cause rests entirely on the shoulders of the very same doctors who decry out-of-hospital birth.

What do you share with the low-risk families you work with about home or freestanding birth center birth options in your community? Do you feel that people believe that out-of-hospital birth is not a safe option for them? - SM

References

Bovbjerg, M. L., Cheyney, M., Brown, J., Cox, K. J., & Leeman, L. (2017). Perspectives on risk: Assessment of risk profiles and outcomes among women planning community birth in the United States. Birth.

Martin, J. A., Hamilton, B. E., Osterman, M. J., Driscoll, A. K., & Mathews, T. J. (2017). Births: Final Data for 2015. National vital statistics reports: from the Centers for Disease Control and Prevention, National Center for Health Statistics, National Vital Statistics System, 66(1), 1.

Moraitis, A. A., Oliver-Williams, C., Wood, A. M., Fleming, M., Pell, J. P., & Smith, G. C. S. (2015). Previous caesarean delivery and the risk of unexplained stillbirth: retrospective cohort study and meta-analysis. BJOG: An International Journal of Obstetrics & Gynaecology, 122(11), 1467-1474.

About Henci Goer

Henci Goer, award-winning medical writer, and internationally known speaker, is an acknowledged expert on evidence-based maternity care. Her first book, Obstetric Myths Versus Research Realities, was a valued resource for childbirth professionals. Its successor, Optimal Care in Childbirth: The Case for a Physiologic Approach, won the American College of Nurse-Midwives "Best Book of the Year" award. Goer has also written The Thinking Woman's Guide to a Better Birth, which gives pregnant women access to the research evidence, as well as consumer education pamphlets and articles for trade, consumer, and academic periodicals; and she posts regularly on Lamaze International's Science & Sensibility. Goer is founder and director of Childbirth U, a website offering narrated slide lectures at modest cost to help pregnant women make informed decisions and obtain optimal care for themselves and their babies.