A population-based study from South Australia on all births and perinatal deaths between 1991 and 2006 – one of the studies included in the review – reported that the overall perinatal mortality rate of nonhospital deliveries was similar to that for planned hospital births. However, there was a 7-fold higher risk of intrapartum death and a 27-fold higher risk of death from intrapartum asphyxia (Med. J. Austr. 2010:192;76-80).
A key complicating factor in planned home birth is the frequent need for transport to the hospital. Maternal and fetal reasons for transport during labor include failure for labor to progress, unbearable labor pain, fetal malpresentation, abrupt deterioration of fetal heart rate, uterine rupture, acute bleeding, placental abruption, acute sepsis, and cord prolapse.
Neonatal reasons for transport include signs of respiratory distress, unexpected very low or very high birth weight, and acute sepsis. Indeed, in the 2010 meta-analysis, respiratory distress and failed resuscitation contributed disproportionately to neonatal deaths among planned home births.
The 2010 review concluded that more data are necessary before drawing any conclusions regarding maternal mortality in planned home vs. planned hospital delivery. Although rare, preventable maternal death may nevertheless sometimes occur. Just recently, an Australian midwife and home-birth advocate died from postpartum hemorrhage after attempting to deliver her second child at home.
These complications and high-risk conditions are often impossible to predict, even with the best possible prenatal screenings, risk assessments, and fetal surveillance during labor. Women need immediate access to in-hospital care and emergency cesarean delivery.
Even studies that generally support home birth have reported high rates of transport. For example, the recent Birthplace in England prospective cohort study reported transport rates from nonobstetric units to the hospital of 36%-45% for nulliparous women and 9%-13% for multiparous women (BMJ 2011:343;d7400).
Adverse outcomes were similarly much higher in this study in women having their first baby at home. For women "without any complicating factor at the start of care in labour," the adjusted odds ratio of a primary outcome event for births planned at home, compared with planned obstetric unit births, was 1.59. The primary outcome in this study was defined as a composite measure of perinatal mortality and intrapartum-related neonatal morbidities (which include early neonatal death, neonatal encephalopathy, meconium aspiration syndrome, and brachial plexus injury).
This adjusted odds ratio of an adverse event increased to 1.75 in a subgroup analysis of nulliparous women, and to 2.8 when the sample was restricted to nulliparous women with no complications at the start of labor. Although the authors did not elucidate on the issue of transport, the 59%-75% increase in a poor primary outcome may largely be attributed to the delay in access to hospital care from transport time.
In the Netherlands, where there is a long tradition of organized home birth with well-trained midwives, 49% of primiparous and 17% of multiparous women are transported during labor (BJOG 2008:115:570-8). Research done in the Netherlands also shows that women who are transferred to a hospital have a significantly higher rate of operative vaginal and secondary cesarean delivery.
In the United States, women tend to envision that any complications can be easily mitigated by a rapid and seamless transport and transition to the hospital, but in reality, even the best of transport systems experience unavoidable delays that can result in increased mortality and morbidity.
The standard of care in the United States is that "decision to incision" should take no more than 30 minutes, and ACOG has said in a recent practice bulletin that once a decision for operative delivery has been made in the context of a Category III EFM tracing, it should be accomplished as expeditiously as possible. The standards outside the United States are much the same, if not stricter. In Germany, for instance, 20 minutes is the standard used in the assessment of perinatal centers.
None of these standards of care can be consistently met when pregnant patients have started the labor process at home and then are transported to obstetric units, and the inherent problems with transport are largely irremediable even with significant investments of capital. Moreover, even if rates of emergency transport were low, there still should be considerable concern given the severity and frequency of the reasons for transfer.
Ethics, our response
The RCOG-RCM statement emphasizes the psychosocial importance of planned home birth and says that the focus should not be exclusively on the physical safety of planned home birth.
Other supporters of home birth, including some experts in the United States, focus on the absolute risk of planned home birth rather than the relative risk. According to these experts, in the broader context, the numbers of adverse outcomes are so small that it is ethically acceptable to support a patient’s desire for home birth. The ACOG, meanwhile, says that pregnant women should be informed of the risks of planned home birth, as summarized in the 2010 review.