Saraswathi Vedam's deeply disingenuous annotated guide to the homebirth literature

I never cease to be amazed at the pervasive contempt in which professional homebirth advocates hold their own followers.

• Contempt for the intelligence of their followers: they are confident that followers can be easily tricked with long lists of citations;
• Contempt for their unfamiliarity with forms of scientific literature: they are confident that their followers will believe something is a scientific paper if they just make it look like a scientific paper; but most of all,
• Contempt for the obligations they owe their followers: they have no compunction about tricking them into risking the lives of their babies by using mendacious means to convince them of homebirth safety.

Saraswathi Vedam's Homebirth: An Annotated Guide to the Literature © is a case in point. Vedam has helpfully provided a list of 66 separate citations. But if you read each and every citation, as I have done, you will find that only 3 of the 66 "citations" support the claim that homebirth is as safe as hospital birth.

Vedam was one of the organizers of the recent Homebirth Consensus Summit, a public relations ploy to elevate the status of homebirth midwives, giving the impression that they were "invited to the table" by the expedient of creating the table and issuing all the invitations.

Vedam describes her Guide:

This annotated bibliography provides citations and critical appraisal of original studies on home birth.

It's all very official and "scientific" looking, complete with elaborate subcategories and a table of contents. It's true purpose is betrayed by a statement on the first page:

Please distribute widely.

In other words, it's a document designed for advocacy of homebirth, not truth about homebirth safety. And homebirth advocacy organizations, including Citizens for Midwifery (CfM), the Center for the Childbearing Year, and the Coalition for Improving Maternity Services (CIMS) are duly offering copies of the Guide on their websites.

What does the Guide offer?

Let's start with the title. Reading it, you might think that the guide provides an overview of scientific citations and original scientific research on home birth. You'd be wrong.

Sure, there are some scientific studies in there, but out of 66 total "citations," fully 25, more than 1/3, are not scientific studies at all, 1 was never published and 1 was published in a non-peer reviewed publication.

Well, that's not too bad, is it? Vedam has compiled and annotated a list of 39 studies that "support" homebirth and its safety.

Not exactly.

Of the 39 actual scientific citations:
1 was publicly retracted
17 do not address the issue of homebirth safety.

Okay, so in an effort to support homebirth, Vedam has compiled and annotated 21 contemporary scientific studies that address the issue of homebirth safety. And they show that homebirth is safe, right?

Not exactly.

Of the 21 scientific studies:
2 are underpowered
4 compared homebirth to a hospital group containing high risk women

That leaves 15 studies of which:
12 showed that homebirth had an INCREASED risk of perinatal or neonatal death
3 showed homebirth may be as safe as hospital birth under very strict conditions

That's right. Out of 66 separate citations in Vedam's Guide, only 3 show that homebirth is as safe as hospital birth, 2 from Canada and 1 from the Netherlands. The results from the Dutch study are called into question by the fact that it compared homebirth with a midwife to hospital birth with a midwife. A more recent study showed that low risk birth (home or hospital) with a Dutch midwife has a HIGHER perinatal mortality rate than high risk delivery with a Dutch obstetrician.

Of course, nothing brings the point home like an illustration, such as the view of a typical page of the Guide posted below.



You can view the complete document, with my annotations, here:

Dr. Amy's Annotated Guide to the Annotated Guide

Vedam's deeply disingenous Guide shows how professional homebirth advocates use the forms and language of science to mislead their readers and the contempt that they have both for their readers and for the truth.


This piece first appeared on The Skeptical OB in December 2011.

No wonder Colorado homebirth midwives hid their 2010 death rates

Each year, licensed Colorado homebirth midwives (certified professional midwives, CPMs) are mandated to report their safety statistics. As I detailed in a post about the 2009 statistics, in every year since homebirth midwives were first licensed in 2006, the midwives had a death rate that exceeded the state as a whole (including all races, all gestational ages, all pregnancy complications, all pre-existing medical conditions). Even worse, from 2006 to 2009, the death rate rose dramatically.

Imagine my surprise, therefore, when I looked for the 2010 statistics and learned that the homebirth midwives had failed to released them. Now I know why. They were ever more horrendous than the 2009 statistics.

How did I obtain the 2010 statistics? It's not because the midwives publicly released them. No, they were required to hand them over after a Colorado citizen filed a CORA petition (Colorado Open Records Request). She shared those statistics with me, both the raw data and the summary data complied by the midwives themselves.

I've created a table of mortality rates from 2006-2010.



As you can see, the perinatal death rate for planned homebirth with a licensed Colorado midwife rose from 11.3/1000 in 2009 to an astounding 16.4/1000 in 2010! Compare that to the overall perinatal mortality rate for the entire state of Colorado (all races, all gestational ages, all pregnancy complications, all pre-existing medical conditions) of 6.3/1000.

Colorado homebirth midwives cared for fewer than 1000 patients and managed to lose 15 babies. It is difficult to convey just how appallingly large a number that is. Colorado licensed midwives have a perinatal mortality rate nearly triple that of the state as a whole. That actually dramatically understates the danger of homebirth in Colorado since the correct comparison (if it were available) would be to the mortality rate of low risk white women at term with normal sized babies.

It's easy to understand why Colorado homebirth midwives hid their 2010 statistics; they are an appalling indictment of the midwives and irrefutable evidence that they are unfit and unsafe practitioners.

This is the same tactic being employed on the national level by the Midwives Alliance of North America (MANA). MANA collected death rates for the years 2001-2008. While they were collecting the statistics, they publicly promised they would be used to demonstrate the safety of homebirth midwives, but once they saw the results, they decided to hide them instead.

Now that Colorado homebirth midwives have been licensed for 5 years and had appalling and RISING death rates over that period, it is time to acknowledge the obvious. Licensed homebirth practitioners are grossly incompetent. They lack the education and training required of ALL other midwives in Europe, Canada and Australia and required of US nurse midwives (CNMs). It is time to end the experiment and declare it a resounding failure.

Homebirth in Colorado (and everywhere else in the US) is not about babies, and it is not about birth. It is about a bunch of high school graduates who couldn't or wouldn't get real midwifery training and made up a pretend credential they award to themselves to fool an unsuspecting public.

Colorado homebirth midwives are unethical in the worst possible way; they don't care how many newborn lives are sacrificed, indeed that will go to great lengths to hide how many newborn lives are lost, in an effort to continue collecting fees for appallingly incompetent care. Of course, they are merely copying the behavior of their national leaders. The entire leadership of American homebirth, from the President of MANA on down should be ashamed of themselves.

How do American homebirth midwives handle their mistakes? They bury them --- both literally and figuratively.


This piece first appeared on The Skeptical OB in June 2012.

Uterine rupture: how much time do you have to save the baby?

A new study to be published in the April issue of Obstetrics and Gynecology demonstrates that in the wake of a uterine rupture, providers have no more than 18 minutes to deliver the baby before the baby experiences significant hypoxia, and only 30 minutes until the baby suffers major neurological impairment.

The paper, entitled Uterine Rupture With Attempted Vaginal Birth After Cesarean Delivery: Decision-to-Delivery Time and Neonatal Outcome by Calla Holmgren et al. was undertaken to provide the most accurate information possible about the conditions needed to make attempted vaginal birth after cesarean (VBAC) as safe as possible.

The authors note:

The increasing rate of primary and repeat cesarean delivery in the United States is of concern to physicians and patients, and vaginal birth after cesarean delivery is considered to be one way to lower the overall cesarean delivery rate. Trial of labor after cesarean delivery (TOLAC), which peaked at 31% in 1998, has decreased progressively since (8.5% by 2006), primarily because of issues surrounding uterine rupture. Although rupture of the uterus during TOLAC is rare, it can be devastating for both the mother and neonate when it occurs, and it is a major liability risk for physicians. The American College of Obstetricians and Gynecologists’ guidelines advise physicians that TOLAC is most safely undertaken in hospitals where staff can immediately carry out an emergency cesarean delivery. This view is based on the premise that the ability to rapidly intervene will minimize adverse neonatal outcomes. However, immediate availability is loosely defined, and it is not clear how rapidly the fetus must be delivered after uterine rupture to prevent neonatal death or neurologic sequelae. The purpose of this study was to examine whether an association exists between neonatal outcomes and the time from diagnosis of uterine rupture to delivery of the neonate.

In other words, should hospitals refuse a trial of labor to women with a previous C-section if they cannot guarantee that both an obstetrician and and anesthesiologist are on site to start a C-section with less than a half hour?

What did they look for?

The primary adverse outcome was defined as an abnormal umbilical pH level less than 7.0 or a 5-minute Apgar score of 7 or less. Secondary adverse outcomes included fetal or early neonatal death and neonatal neurologic injury attributed to uterine rupture. Neonatal neurologic injury was defined as otherwise unexplained seizures, clinically obvious cerebral palsy, or developmental delay attributable to hypoxia resulting from the uterine rupture.

Who was included in the study?

Within the 10 hospitals studied, 40,772 women were identified with a prior cesarean delivery between January 1, 2000, through December 31, 2009. Of these, 11,195 women (27.5%) attempted TOLAC, with successful vaginal delivery for 9,419 (84.1%) patients... In total, there were 36 cases of documented uterine rupture (0.32%) during TOLAC.

What did they find?

Of the 36 patients, 13 (36.1%) met our criteria for a primary adverse outcome of umbilical artery pH level less than 7.0 or 5-minute Apgar score less than 7. These patients were compared with the 23 patients without this outcome. Median (range) time to delivery for the primary adverse outcome group (n=13) was 19 (9–40) minutes compared with 14 (0 –38) for the nonadverse outcome group. Results after stratifying the sample by hospital type yield a similar result, with those experiencing the primary outcome having, on average, a 5.5-minute (95% confidence interval [CI] 0.0 –15.0) longer time to delivery than those who did not experience the outcome...

Seventeen neonates (47.2%) were delivered less than 18 minutes after identification of uterine rupture. Of these, two neonates had an abnormal 5-minute Apgar score, but both of these neonates had an umbilical pH level greater than 7.0 and none had neurologic injury. Eighteen patients were delivered more than 18 minutes after suspicion of uterine rupture (50.0%). Of these, 11 met criteria for a primary adverse outcome and three met criteria for an adverse secondary outcome. One patient did not have suspected uterine rupture during labor.

Seventeen neonates (47.2%) were delivered less than 18 minutes after identification of uterine rupture. Of these, two neonates had an abnormal 5-minute Apgar score, but both of these neonates had an umbilical pH level greater than 7.0 and none had neurologic injury. Eighteen patients were delivered more than 18 minutes after suspicion of uterine rupture (50.0%). Of these, 11 met criteria for a primary adverse outcome and three met criteria for an adverse secondary outcome. One patient did not have suspected uterine rupture during labor.

A chart of the data makes the relationship between time to delivery and risk of adverse outcomes quite clear.



More than 83% of babies delivered more than 30 minutes after uterine rupture experienced major neurological complications.

As the authors explain:

Our study focused on serious neurologic morbidity in cases of confirmed uterine rupture during TOLAC. In 36 cases of acute uterine rupture, there were no fetal or neonatal deaths. Delivery within less than 18 minutes was associated with adverse primary outcome in two cases, but this was based on a 5-minute Apgar score less than 7; both neonates had normal umbilical pH levels. Three neonates in our study sustained long-term neurologic damage. These neonates were delivered 31, 40, and 42 minutes after uterine rupture was suspected on clinical grounds. When uterine rupture was identified in a timely fashion and delivery occurred in less than 30 minutes, there was no long-term neonatal morbidity in our study. However, delivery within 30 minutes did not prevent every case of low umbilical cord pH level or low 5-minute Apgar score, so these results should be interpreted with caution...

The authors conclude:

Uterine rupture during TOLAC is a rare but serious complication that requires prompt recognition and delivery of the fetus. The response time necessary to prevent neonatal injury has been uncertain and controversial. In our study, all neonates delivered within 18 minutes from decision to delivery had normal umbilical cord pH levels. Delivery within 30 minutes was associated with good long-term outcomes...

This is an important study that has the potential for wide impact. The study strongly confirms the ACOG recommendation that babies should be delivered as soon as possible in the wake of a uterine rupture. Intervals longer than 18 minutes resulted in demonstrable hypoxia and intervals longer than 30 minutes resulted in major neurological impairment. Studies like these make it extremely unlikely that hospitals and malpractice insurers will liberalize access to VBAC.


This piece first appeared on The Skeptical OB in March 2012.

International comparisons of neonatal and infant mortality are invalid

The annual meeting of the Society for Maternal-Fetal Medicine is currently being held in Dallas. Two different papers will be presented today, both of which highlight the increased risks of homebirth.

The first is Neonatal outcomes associated with intended place of birth: birth centers and home birth compared to hospitals (abstract 65) by Cheng, Snowden and Caughey. According to the authors:

This was a retrospective cohort study of singleton live births that occurred in 2008 in the U.S. that had specified birthing facility information. Deliveries were categorized by location of occurrence: hospitals, birthing centers, or intended home births...

What did they find?

While the risk of cesarean delivery was much lower for women who delivered/or intend to deliver outside of hospitals (0.02-4% vs. 24%, <0.001), the odds of 5-minute Apgar score <7 and neonatal seizure was significantly higher for intended home births compared to hospital birth.

In other words, while homebirth has a dramatically lower C-section rate, the price is double to triple the rate of birth asphyxia. This study actually substantially underestimates the risk of these serious complications at homebirth because it compares homebirth to all risk hospital birth instead of low risk hospital birth.

The second study is entitled Does planned home birth affect neonatal mortality? (abstract 563) by Joel Larma.

This is a population based retrospective cohort study of all births between 37 and 42 weeks gestation using the National Health Center for Vital Statistics 2005 Linked Birth/Infant Death Cohort Data Set. The primary outcome was neonatal mortality and the primary predictor was planned home birth. The referent group for the regression model was births that occurred in a hospital...

The authors did not separate homebirths attended by CNMs from homebirths attended by non-nurse midwives. The analysis showed that homebirth more than doubled the risk of neonatal death. This actually underestimates the risk because it compares homebirth to term hospital birth in women without pre-existing medical conditions, but apparently includes hospital births with pregnancy complications.

The adjusted OR for neonatal mortality among individuals having a planned home birth was 2.32 (95% CI 1.33, 4.06) after controlling for the aforementioned covariates [age, race, marital status, education, prenatal care, tobacco use, composite medical comorbidities].

CONCLUSION: The odds of neonatal mortality are significantly increased among those individuals having a planned home birth compared to those individuals giving birth in the hospital.

The amount of data on planned homebirth is slowly growing and the findings are remarkably robust. These studies, like all the existing scientific evidence, state and national statistics show that homebirth doubles or triples the rate of neonatal death and other adverse outcomes, and that the analyses almost certainly underestimate the real increased risks at homebirth.


addendum: These studies underestimate the risk even further because, as far as I can determine, bad outcomes that occurred after homebirth transfer are included in the hospital group and removed from the homebirth group. The real number of bad outcomes and deaths is higher than what the authors were able to determine.


This piece first appeared on The Skeptical OB in March 2012.

Two new studies show increased risk of death, serious complications at homebirth

The annual meeting of the Society for Maternal-Fetal Medicine is currently being held in Dallas. Two different papers will be presented today, both of which highlight the increased risks of homebirth.

The first is Neonatal outcomes associated with intended place of birth: birth centers and home birth compared to hospitals (abstract 65) by Cheng, Snowden and Caughey. According to the authors:

This was a retrospective cohort study of singleton live births that occurred in 2008 in the U.S. that had specified birthing facility information. Deliveries were categorized by location of occurrence: hospitals, birthing centers, or intended home births...

What did they find?

While the risk of cesarean delivery was much lower for women who delivered/or intend to deliver outside of hospitals (0.02-4% vs. 24%, <0.001), the odds of 5-minute Apgar score <7 and neonatal seizure was significantly higher for intended home births compared to hospital birth.

In other words, while homebirth has a dramatically lower C-section rate, the price is double to triple the rate of birth asphyxia. This study actually substantially underestimates the risk of these serious complications at homebirth because it compares homebirth to all risk hospital birth instead of low risk hospital birth.

The second study is entitled Does planned home birth affect neonatal mortality? (abstract 563) by Joel Larma.

This is a population based retrospective cohort study of all births between 37 and 42 weeks gestation using the National Health Center for Vital Statistics 2005 Linked Birth/Infant Death Cohort Data Set. The primary outcome was neonatal mortality and the primary predictor was planned home birth. The referent group for the regression model was births that occurred in a hospital...

The authors did not separate homebirths attended by CNMs from homebirths attended by non-nurse midwives. The analysis showed that homebirth more than doubled the risk of neonatal death. This actually underestimates the risk because it compares homebirth to term hospital birth in women without pre-existing medical conditions, but apparently includes hospital births with pregnancy complications.

The adjusted OR for neonatal mortality among individuals having a planned home birth was 2.32 (95% CI 1.33, 4.06) after controlling for the aforementioned covariates [age, race, marital status, education, prenatal care, tobacco use, composite medical comorbidities].

CONCLUSION: The odds of neonatal mortality are significantly increased among those individuals having a planned home birth compared to those individuals giving birth in the hospital.

The amount of data on planned homebirth is slowly growing and the findings are remarkably robust. These studies, like all the existing scientific evidence, state and national statistics show that homebirth doubles or triples the rate of neonatal death and other adverse outcomes, and that the analyses almost certainly underestimate the real increased risks at homebirth.


addendum: These studies underestimate the risk even further because, as far as I can determine, bad outcomes that occurred after homebirth transfer are included in the hospital group and removed from the homebirth group. The real number of bad outcomes and deaths is higher than what the authors were able to determine.


This piece first appeared on The Skeptical OB in February 2012.

The death toll of California homebirth

The state of California has released a comprehensive summary of outcomes of California licensed homebirth midwives of the year 2010. The reports makes for disturbing reading. Homebirths exceed low risk (and sometimes high risk) hospital birth on almost every negative outcome including deaths.

Before we look at the outcomes, let's look at whether California licensed homebirth midwives comply with their own rules.

The first thing to note is that although all midwives are required to report outcome statistics, 16% never bothered to report their outcomes.

The second is that midwives are required to consult with and generally transfer care to obstetricians if a baby is known to be breech or in the case of twins. Nonetheless, California midwives delivered 13 breech babies and 5 sets of twins at home.

Let's look at the basic statistics.

There were 2245 who planned homebirths at the onset of labor. 1840 delivered at home, for a transfer rate of 18%. There were 205 C-sections for a C-section rate of 9.1%.

How about outcomes? Simply put, the outcomes are dreadful as the chart below demonstrates.



The fetal mortality rate was 11/1000 compared to the California rate for white women (all gestational ages, all pre-existing medical conditions, all pregnancy complications) of 4.9/1000 for a rate more than double that expected.

The intrapartum mortality rate was 2.6/1000 compared to the expected rate of 0.3/1000, for a rate more than 8 times higher than expected.

The neonatal mortality rate was 0.9/1000 compared to the national rate for low risk white women of 0.4/1000, for a neonatal mortality rate more than double that expected.

A perinatal mortality rate of 12/1000 compared to the California rate for white women (all gestational ages, all pre-existing medical conditions, all pregnancy complications) of 5/1000 for a rate more than double that expected.

These numbers potentially under-count the real death rates for 2 reasons. First, among reported perinatal outcomes after transfer 11 were classified as unknown. Second, fully 16% of California homebirth midwives failed to report their outcomes.

How about birth complications? There were quite a few considering that the mothers were extremely low risk.

maternal

4 cases of massive PPH
1 case of seizure/shock
10 cases of retained placenta

neonatal

1 case of birth injury
2 cases of abnormal cry/seizures/loss of consciousness
6 cases of clinically apparent infection
9 cases of significant cardiac of respiratory issues
3 cases of 5 minute Apgar less than 6

Untimately, 14 mothers suffered serious complications resolved by 6 weeks and 1 mother suffered serious complications that persisted beyond 6 weeks. 21 infants suffered serious complications resolved by 6 weeks and 4 suffered serious complications that persisted beyond 6 weeks.

What conclusions can we draw from this data?

First and most important, despite the fact that the homebirth population presumably represents the lowest of low risk patients, the neonatal death rate is double that expected for low risk white women. The overall perinatal mortality rate is double that for all white women in California (including premature births, all pre-existing medical conditions, and all complications of pregnancy).

Second, homebirth in California has an extraordinarily high rate of intrapartum death, more than 8 times higher than the intrapartum death rate for women of all races, all gestational ages, all pre-existing medical conditions and all complications of pregnancy. While rigorous intermittent auscultation might be equivalent to electronic fetal monitoring under experimental conditions, that is clearly not true of intermittent auscultation as practiced by California homebirth midwives. In a population this size, we would expect that every woman who enters labor with a live baby will deliver a live baby. Instead, 6 babies died in the course of labor, because midwives didn't recognize fetal distress and/or didn't transfer in a timely fashion if they did recognize it.

Third, these results probably underestimate the dangers of homebirth in California because a substantial proportion of information is missing.

The bottom line is that homebirth in California increases the risk of perinatal and neonatal death by 100% or more. California homebirth midwives, like all homebirth midwives, "trust birth" and birth, far from being trustworthy, is inherently dangerous.


California birth outcomes can be found here.
For more information on the source of the homebirth statistics: Licensed Midwife Annual Report user guide.

addendum: Ideally, the California homebirth statistics should be compared to the mortality rates for California women in 2010 without any of the following risk factors (in order of importance): African descent, prematurity, pre-existing medical conditions and pregnancy complications that occur before onset of labor. Unfortunately, the mortality rate of that group is unavailable, so each comparison is made with the available group having the least number of risk factors.

In the case of neonatal mortality, the comparison group is hospital birth for low risk white women at term for 2007; for intrapartum mortality the only available group is all women; for fetal mortality the best available group is California white women of 2009; similarly for perinatal mortality the best available group is California white women of 2009.

Practically speaking, the substitution of these groups means that in all cases besides neonatal mortality, the correct comparison group would have much smaller mortality rates and that, therefore, the real increased risk of homebirth is much higher than that depicted here.

It is also important to note that homebirth appears to be associated with dramatically higher rates of intrapartum mortality, a vanishingly rare event among low risk women at term. Therefore, the figures that I routinely quote demonstrating that homebirth has a neonatal mortality rate at least 3 times higher than comparable risk hospital birth, dramatically underestimate the true risk.


This piece first appeared on The Skeptical OB in February 2012.

Near-miss maternal mortality

Maternal mortality has dropped 99% in the past 100 years. A maternal death is now, fortunately, a rare event. Attention, therefore, is shifting to maternal morbidity, in particular, life-threatening morbidity. The results of a new study are instructive.

Near-Miss Maternal Mortality: Cardiac Dysfunction as the Principal Cause of Obstetric Intensive Care Unit Admissions by Small et al. will be published in the February 2012 issue of Obstetrics and Gynecology. The title gives away the principle finding; heart disease is the most common cause of maternal ICU admission.

The study took place at Duke University from January 2005 to April 2011. There were 19,575 births and 5 maternal deaths for a maternal mortality rate of 25/100,000. That is approximately double the US maternal mortality rate, but that is only to be expected in a tertiary center that receives the most complicated cases from the surrounding area. There causes of the five maternal deaths were: two from metastatic cancer, two secondary to cystic fibrosis, and one the result of sepsis.

The authors then looked at maternal admissions to the intensive care unit:

Ninety-four obstetric patients—five per 1,000 deliveries—were admitted to ICUs. Eight declined participation in the study. Eighty-six patients were included in this analysis.

... African American women comprised the largest population admitted to the ICU (45%). Significant differences were found by race and ethnicity in the following variables: parity, BMI, and marital and insurance status. African American (mean 35) and Hispanic women (mean 36) had significantly higher BMIs than white women (mean 28). African American and Hispanic women were also more likely to have Medicaid or no insurance and were more likely to be unmarried and multiparous.

The following table shows the reasons for ICU admission.



The authors write:

... The leading admission diagnosis for pregnant and postpartum women was maternal cardiac disease (36%). Maternal hemorrhage (both obstetric and nonobstetric) was the second leading reason for admission (29%). Hypertensive disease accounted for 9% of ICU admissions...

The majority of cardiac conditions prompting ICU admission resulted from cardiomyopathy. Acute complications associated with peripartum cardiomyopathy
comprised the majority of this group. Congenital heart disease is the underlying etiology for many of these valvular lesions and cardiomyopathies. Congenitally
acquired conditions were the second leading cause of maternal cardiac ICU admissions...

The findings of this study are notable for the following:

1. Race is a major risk factor for near-miss maternal mortality.
2. Obesity (BMI greater than 30) is a major risk factor for near-miss mortality.
3. The leading cause of near-miss mortality is cardiac disease.
4. Infection and bleeding account for only one third of the near-miss events.

This paper demonstrates that near miss-maternal mortality, like maternal mortality, is the result of complex medical and non-medical factors. Both race and maternal BMI appear to play important roles. Pre-existing medical conditions account for a substantial proportion of near-miss maternal mortality. The traditional causes of maternal mortality and near-miss mortality have been eclipsed by cardiac complications of pregnancy.

In other words, contrary to the claims of natural childbirth and homebirth advocates, maternal mortality and near-miss maternal mortality are not related to obstetric interventions. The most common risk factor is pre-existing maternal health issues. Women with serious medical problems (including obesity) prior to pregnancy are the ones most likely to develop life threatening medical problems during pregnancy and childbirth.


This piece first appeared on The Skeptical OB in January 2012.