Apgar Wars ~ 5th in series: The Consensus of the scientific literature support relative safety of PHB

by faithgibson on September 23, 2013

in Contemporary Childbirth Politics

Since the early 1970s, over a hundred peer-reviewed studies on the comparative safety PHB have been published. During this 43-year period of time, some of these studies were large, some small, some very good, others not so good.

We would all like to live in a world where none was the number of newborns that died just before or after birth, but the facts tell us that regardless of planned place-of-birth, neonatal (live birth to 28 days of age) mortality outcomes are statistically equivalent for all birth settings — OOH birth centers, PHB and hospitals.  The general consensus (aggregate of all PHB comparison studies) is about 2 neonatal deaths per 1,000.

So for every thousand live-births in essentially healthy women with normal pregnancies giving birth at term (37 or more completed weeks of pregnancy) — regardless of the setting — approximate 998 babies will be fine and two will will die within the first 28 days of their life.

So far, the only medical action that has effectively reduced this background neonatal mortality rate of 2 per thousand has nothing to do with the management of normal labor at the term of pregnancy or the birth itself.

Through the use ultrasound technology during the 1 and second trimesters of pregnancy, in combination with various kinds of prenatal genetics testings, it is often possible to identify the approximately one baby out of a thousand that has a life-threatening birth defect. When parents agree to have this testing performed (many families choosing OOH midwifery don’t) and when they are willing to have affected pregnancies terminated at a pre-viable stage (many are not), then aborting these affected pregnancies reduces the rate of stillbirths and neonatal deaths by about 1 per 1,000.

However, this does not reduce the total number of babies that die. It just moves their mortality statistics from birth certificate data to the informal records of pregnancies aborted due to congenital anomalies. This latter number does not show up in nationally collected data on the numbers of births and deaths. Obviously, there are NO five-minute Apgars being collected in these cases, so medical providers who increase early diagnosis and pre-viable terminations of affected pregnancies will ultimately reduce the number of low or zero 5-minute Apgars.

One PHB comparison study from Australian identified also an increased perinatal loss of 1.6 fold for home labor or birth, but only for pregnancies that were already identified as high risk or included a recognized complication. For the vast majority of home birth practitioners in the US, risk factors such as twins, breeches, post-mature pregnancies with abnormal NSTs and bio-physicial findings, and labors where there is significant meconium in the amniotic fluid would in most cases risk the mother out for a planned labor at home.

However, what I considered particularly interesting insight on in the study was as opinion stated in the introduction:

“Despite decades of political and academic debate, the relative merits of home versus hospital birth remains unproven. This is likely to remain so. Comparisons that are sufficiently unbiased and large enough to address crucial safety issues are unlikely to be forthcoming [1,2].

Although home and hospital offer different benefits for birth, neither has ‘standard care’ characteristics. In fact the range from safe to unsafe practice may be wider within each location that it is between them.

Addressing what constitutes safe practice at home may be a more pivotal concern than attempting to quantify the theoretical differences attributable to place of birth.” **emphasis added 

Ref: Bastian H et al; Perinatal death associated with planned home birth in Australia: population based study. BMJ 1998;317:384-8.

The sentence “the range from safe to unsafe practice may be wider within each location that it is between them” and “addressing what constitutes safe birth practice at home” really are the crux of the planned place-of-birth issue.

Bottom Line: Parity for all Planned Places-of-Birth

Stated more simply, OOH birth settings are something of a ‘red herring’, as no particular place-of-birth — home, hospitals, or birth centers — can either claim to produce superior results (i.e., virtual elimination of bad outcomes) nor can any of them point a finger at another and claim (in more polite terms of course) the either home or hospital is “killing babies”.

As the number of families choosing OOH births has increased, and the pool of trained midwives providing community-based birth services has gotten larger, there has been a big jump worldwide in the number of large, well-designed retrospective and prospective studies published in English the last 15 years. This is in general a good thing and the outcomes of these newer, often larger or better designed studies has reaffirmed the over-all consensus of the previous 100 studies. {see list}

In addition to a accounting for neonatal outcomes, newer studies have included other birth-related outcomes that were specific to in-hospital and out-of-hospital settings. One of the most important has been a comparison of medical interventions and surgical procedures based on the ‘planned’ place of birth. That means the number and type of interventions used on women planning a hospital birth were compared to women who had labored and gave birth at home and women who labored at home but prior to the birth (maybe many  hours or even a day) before the birth, were transferred to the hospital.

Studies that compare the frequency of obstetrical interventions have generally determined that healthy women who plan an OOH birth have 2 to 10 timesreduction in both interventions and Cesarean section deliveries, and of course all the downstream complication known to be associated with operative delivery.

However, this large cohort of positive studies has always included a trickle of notable exceptions. These studies from the US and elsewhere use data they claim proves OOH childbirth — especially home birth — to be exceedingly dangerous, especially for the unborn or newborn baby.

In the last 15 or so years, the role of a few ‘outlier’ studies (two in particular) has taken a decided ‘up-tick’  influence over the public discourse. It is not a matter of greater numbers — there are only about a half-dozen of these highly critical studies — but efforts to leverage their findings into the media have been both persistent and successful.

This newer, more aggressively negative cohort has focused heavily on the idea that merely planning an OOH birth, especially a home birth, is order of magnitude more risky as measured by neonatal deaths, zero-Apgars at 5 minutes, and variously defined neurological complications for babies either born at home, or whose parents planned a home birth but were transferred to the hospital either before or after the birth.

While the actual numbers of critical studies are tiny, they have frequently misuses or distorted information in prior studies (examples already recorded by me in long ver. PANG critique). In many cases, studies that very specifically found statistically favorable outcomes for PHB were referred to as proving the exact opposite.

The  methodologies used seems particularly  useful for defending high medical-intervention models of care (i.e, hospital), while allowing the authors to cherry-pick data generated the most alarming of headlines about ‘other’ midwives (CPMs instead of CNMs) and OOH (i.e.. low medical-intervention settings).

For midwives who actually attend OOH births one of the most disturbing and upsetting aspects of these studies is the wildly wrong ideas by obstetrician-researchers about the idea of “planned home birth” as a topic of research. The authors also did not understand the idea of “planned” home birth from the perspective of the practitioner.

The use of the term “birth” in PHB can only applied as a description of what has already happened. A childbearing woman had (part-tense) a PHB.

Prior to that the parents had a plan, a prefer, a possibility of giving birth at home, but birth is always something that come AFTER an effective labor. Until a childbearing woman get to term in perfect health with a normal pregnancy and goes into spontaneous progressive labor, then no home “birth” has occurred.

Midwives do not arrive at that determination until we have personally evaluated the mother after active labor has begun. This is the same protocol used by small community hospitals. They do not “plan” to provide intrapartum care to women with obstetrical complications and so routinely evaluate the mother at the onset of labor and transfer those found to be at high risk. So also for midwives.

However midwives and community hospitals still have “unplanned births” occur before transport can be accomplished. Both also have transfers of care, which I consider an indicator of success and not a failure. The Pang study did not/could not make this distinction because the Washington State birth registry does not identify the intended place of birth or the circumstances of hospital transfer. All births after 34 weeks of pregnancy associated with a midwife provider, occurring at home or after transfer to the hospital, were categorized as “planned”.

While the parents expressed their preference for a PHB by engaging the services of a community midwife,  what the midwife is “planning” is to first determine whether or not the mother-to-be is essentially healthy. If not, she is not a candidate for purposefully labor at home and will be referred to an MD. For those women who are healthy, the midwife ‘plans’ to provide primary pregnancy as long as both mother and unborn baby remain healthy and normal.

Not until the mother-to-be completes 37 weeks of pregnancy in perfect health, with a normal pregnancy, does the midwife ‘plan’ to attend her labor at home. Then the pregnant must have a spontaneous on-set of labor (SOOL) and only then will the midwife actually get in her car and begin the process of providing OOH care for labor, a plan that again hinges on a labor is continuing to progress, while mother-to-be and unborn baby are both health and able to tolerate the biological and psychological stresses of labor.

At any moment during the time-line of that labor that any kind of complication is identified or a situation that needs to be medically evaluated, the laboring woman (or in some cases, her newly born baby) will be

Assuming however that a healthy pregnant women is just having a normal labor (85% likelihood) what usually happens, sooner or later, is that the baby normally comes out. We call that birth.

The most egregious offenders based on the unique combination of poor data or flawed methodologies AND the use of PR strategies to make each of these publication into media events.

@@@ series continues with part 6 @@@


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