Cherrypicking stats: bad form and not helpful

by Amy Romano, CNM (Originally published on Science and Sensibility for Lamaze International)

Science & Sensibility contributor, Andrea Lythgoe, has a great post up at her own blog. In The Doula Numbers Game, Andrea shows that many of us may be overestimating – and overstating – the beneficial effects of continuous support from doulas. She argues and I agree that using outdated statistics that yield “better” results could compromise our integrity. Moreover, doing so is not necessary to advocate for greater access to doulas.

Data from the Cochrane Systematic Review show more modest effects of doula support, but they still add up to “clinically significant” benefits, greater satisfacation, and no evidence of harm. Maternal-fetal medicine researchers who evaluated the evidence for a variety of obstetric interventions in the November 2008 issue of the American Journal of Obstetrics and Gynecology called doula support “one of the most effective interventions” (p. 446) for improving outcomes. And they did so without being wowed by the inflated early statistics. (They stuck to the Cochrane.)

It can be extremely difficult to look at research objectively. It is human nature to want to cherrypick the research that furthers our cause the most. We may try to find fault with statistics we don’t like and subconsciously ignore problems or limitations of statistics we do. But improving the safety and effectiveness of maternity care requires that we critically analyze the research, which means recognizing limitations and flaws in the studies we agree with and standing behind solid research even when we don’t like the conclusions. We need not worry. Even with a critical lens, research points to a need to radically reform our system to make it more mother-friendly.

Andrea finishes each post in her Understanding Research series with a familiar plea to practice, practice, practice finding and reading research literature. One of the skills we all should practice is to read the studies that seem to contradict our beliefs or biases. Often, these studies are flawed, and spending time reading them helps us hone our ability to spot methodological problems and logical inconsistencies in other research. Other times the research is valid, and we see circumstances where technology and medicine do in fact improve outcomes. Reading these studies can also shed light on important unanswered research questions.

I highly recommend that readers take a look at Andrea’s post for an example of thoughtful critical analysis of statistics on doula support in labor. It is hard to update our long-held beliefs or alter the ways we teach and practice. But this is just what we’re asking of our “medical model” counterparts. We should lead by example.

How Many Preemies Does it Take?

by Melissa Avery, CNM, PhD, ACNM President

As National Prematurity Awareness Month closes, we’re digesting a lot of statistics. Today, in the US, more than 1,400 babies will be born prematurely. Between the early 1980s and 2006, the rate of premature birth rose by 36%. These are fascinating and disturbing statistics, but as a midwife who is actively engaged in research, there is one companion statistic that startles me even more: From 1992 to 2002, the average gestational age at birth in the US dropped from 40 weeks to 39 weeks.

It does not take a statistician to appreciate that a drop in the average time a baby is born by a full week over the course of just 10 years means something big has been happening. Over 4 million babies are born each year in the US. A substantial increase in the rate of prematurity would be needed to reduce the average time of birth by a full week.

Why the rise in prematurity despite advances in medical knowledge and technology? According to the most recent March of Dimes prematurity summit, the primary reason is not obesity or smoking, as you might expect—it’s labor induction. In 1990, the rate of inductions was 9.5%. By 2006, the rate more than doubled to 22.3%.

Research documents that preterm infants have an increased risk of being admitted to level 2 or 3 nurseries and that important brain development continues all the way to full-term. More recently, late preterm infants (born at 34-37 weeks gestation) have been shown to have a 30-fold increase in complications like respiratory problems, hypoglycemia, and hypothermia.

Certified nurse-midwives and certified midwives have a long history of reserving labor induction for the situations when it is absolutely necessary. The American College of Obstetricians and Gynecologists (ACOG) recently issued a statement calling for an end to inductions prior to 39 weeks unless there is a clear medical indication. Now that the US has enough preemies to impact a national statistic and a national medical organization, let’s support a re-examination of medical indications for labor induction prior to full-term and promote a renewed emphasis on waiting for spontaneous labor and birth.

Moms Reveal Telling Facts About Breastfeeding

by Melissa Garvey, ACNM Writer and Editor

Did anyone listen to the Bravado Breastfeeding Information Council (BBIC) launch event this past Tuesday? I was pleasantly surprised by the amount of solid facts they revealed from their database of 80,000 women. In case you missed it, here’s a snapshot of what they shared:

• First generation breastfeeding moms need special support. Of first generation breastfeeding moms (women whose mothers did not breastfeed), only 40% said they received amazing support from their mothers, 30% hoped for more support, and 10% were actively discouraged in their efforts to breastfeed.
  
  
• Breastfeeding works better with three. 75% of women said their decision to breastfeed was influenced by their partner. As one woman explained, “Without his support, I would have given up in the first week.”
  
  
• Being friendly to breastfeeding moms is good business. Business owners take note: more than 85% of nursing mothers will go out of their way to visit a store or restaurant that is breastfeeding friendly.
  
  
• It’s easy to create a breastfeeding friendly workplace. More than 80% of breastfeeding mothers are committed to continue nursing when they return to work, and they say all they need is a door, a plug, a refrigerator, and a sink. Panelists shared innovative ideas worth passing along on this topic. At one company, moms are able to reserve the breastfeeding lounge via their Outlook calendar. Some companies are also including their breastfeeding policy in the maternity leave paperwork, so women have plenty of time to consider their options and plan ahead.
  

Did you listen in, too? Tell us what you learned.

(Note to women: More information about breastfeeding is available from the Journal of Midwifery & Women’s Health. Read Bringing Your Baby to Breast: Positioning and Latch and What to Expect in the Early Days of Breastfeeding.)

U.S. Infant Mortality Rate Compares Poorly with Europe

by Melissa Garvey, ACNM Writer and Editor

Just in time for Prematurity Awareness Month, the CDC released a new NCHS Data Brief that ranks the U.S. 30th in the world in infant mortality rate. At 6.8 infant deaths per 1,000 live births (5.8 when excluding births less than 22 weeks of gestation), the U.S. falls behind most European countries, Canada, Australia, New Zealand, Hong Kong, Singapore, Japan, and Israel.















What’s the reason for our poor performance in this critical indicator of national health? It’s our “very high percentage of preterm births.”

Since 1984, the percentage of preterm births (infants born before 37 weeks of gestation) in the U.S. has risen 36%. Lowering that percentage appears to be the key to bringing the U.S. infant mortality rate in line with the rest of the developed world.

The Data Brief goes on to show just how dramatic lowering the preterm birth rate in the U.S. could be:

“If the United States had Sweden’s distribution of births by gestational age, the U.S. infant mortality rate (excluding births less than 22 weeks of gestation) would go from 5.8 to 3.9 infant deaths per 1,000 live births—a decline of 33%.”

Sweden and Norway have the lowest infant mortality rates in Europe. Here’s an interesting fact that was not included in the Data Brief: In stark contrast to the U.S., Sweden and Norway (along with most of the developed world) use midwives as their primary birth care providers.

Donate Your Data to Help Mainstream Midwives

One of the most tiring things about being a midwife is having to justify and explain your profession. It’s not common knowledge that most midwives can provide primary care, write prescriptions, and even handle complications in childbirth. It’s frustrating as a midwife supporter, too. We need to keep up our efforts to get the word out!

Part of ACNM’s role is to update midwifery fact sheets that educate consumers, media professionals, policymakers, and others about the profession. While the Childbirth Connection’s Evidence-Based Maternity Care report and a recent Cochrane Review gives us a nice new pool of information to draw from, we still need more data to advocate for the profession and for improved maternity care.

Whether you’re a midwife or a midwife supporter, please help mainstream midwives by donating your data. Imagine what we could do in health care reform, media outreach, and public education if we had proof that midwifery care leads to X% less cesarean sections, X% lower health care bills, and X% higher patient satisfaction.

If you’re an ACNM member, you have until Wednesday, April 15, to complete the Benchmarking Survey, which tracks interventions, maternal health, infant health, and practice information. And you have the remainder of 2009 to take the Core Data Survey, which keeps track of current trends in CNM/CM practice.

If you’re a woman who has given birth, donate your data to the Transparency in Maternity Care Project by taking The Birth Survey—a comprehensive survey designed to give the public access to accurate information about maternity care providers and institutions.