Friday, July 13, 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.


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


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.

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