Wednesday April 15 2009
The study used data on over one million births
“Giving birth at home is as safe as doing so in hospital with a midwife,” BBC news reported. The news service said a large Dutch study has found that for low-risk women, a home birth presents no more danger than a hospital delivery.
This study of 530,000 births demonstrated that the offspring of low-risk women with the same midwife during pregnancy, labour and birth, have the same risk of death or severe illness as those born in hospital. It is important to note that this analysis excluded a large number of women with pregnancy and labour complications, as well as those who had premature onset of labour, required induction or who had additional risk factors such as a previous caesarean or twin pregnancy.
The safety of home births is a subject of frequent debate. These results are encouraging, but it should be noted that these Dutch findings may not be representative of outcomes that would be seen in other countries. The effectiveness and safety of maternity care services relies on well-trained professionals, the facilities to support the woman’s choice and the systems to ensure appropriate access to expert care if needed.
Where did the story come from?
This research was conducted by A de Jonge and colleagues from various medical institutions in the Netherlands. The study was funded by the Dutch Ministry of Health, and published in the peer-reviewed British Journal of Obstetrics and Gynaecology.
What kind of scientific study was this?
This was a nationwide cohort study comparing the perinatal mortality (death around the time of birth) and severe perinatal morbidity (illness) between planned home and hospital births among low-risk pregnant women.
Data for this study was collected from the Netherlands primary care, secondary care obstetric, and paediatric care databases for all women who gave birth between January 2000 and December 2006. The study compared women on their intended place of birth (home, hospital or unknown) for outcomes of death of the baby during birth, up to 24 hours after, and up to seven days after, and admission to a neonatal intensive care unit (as an indicator of severe morbidity).
The study included only low-risk women who were solely under midwife care at the time of onset of labour (in the Netherlands any woman with risk factors identified during pregnancy is placed under the care of an obstetrician in hospital). Such women could choose to give birth either in hospital or at home but would still be under midwife care.
There were a number of factors that excluded women from being in the low-risk group. For example, births requiring pain relief drugs during labour, foetal monitoring or induction of labour would only take place in secondary care under the supervision of an obstetrician, and would no longer be considered to be in the low-risk category. Some women also began labour at home but were later referred to hospital due to complications (such as failure to progress or abnormal foetal heart rate) and transferred into secondary care.
All women categorised as being in the low-risk sample gave birth to a single baby at term (between 37 and 42 weeks gestation) and did not have any medical or obstetric risk factors that were known before labour, such as breech presentation or a previous caesarean section. Additionally, the study excluded women who remained under midwife care but who had risk factors including history of postpartum haemorrhage, those with prolonged rupture of membranes, or a child with congenital abnormality.
What were the results of the study?
Of the 529,688 women in midwife-led care at the onset of labour, 321,307 (60.7%) planned to have a home birth, 163,261 (30.8%) planned to have a hospital birth, and for 45,120 women (8.5%), the intended place of birth was unknown. Women who were planning a home birth were more likely to be aged over 25, to have had previous children and to be of medium-to-high social/economic status than those planning a hospital birth.
Incidence of infant death during labour and the first 24 hours following birth was low for all women in the cohort: 0.05% (84) of all those having hospital birth; 0.05% (148) of all those having a home birth; and 0.04% (16) of those whose planned location of birth was unknown.
No significant differences were found in the relative risks of perinatal mortality among the planned home birth or unknown birth place groups, compared to the planned hospital birth group. This was found in analyses both with and without adjustment for the confounder factors of gestational age, the mother's age, ethnic background, number of previous children and socio-economic status.
Risks of mortality at any time and of admission to neonatal intensive care service was higher among women having their first baby, those giving birth at 37 or 41 weeks gestation, and who were aged over 35.
What interpretations did the researchers draw from these results?
The authors conclude that a home birth does not increase the risks of perinatal mortality and severe perinatal morbidity among low-risk women. However, they say that a successful system relies upon a good maternity care that facilitates the choice of place of birth through the availability of well-trained midwives combined with a good transportation and referral system to secondary care where necessary.
What does the NHS Knowledge Service make of this study?
This study of a very large sample of pregnant women has demonstrated that there is no difference in risk of death or severe illness in the newborn for low-risk women who remain under sole midwife care during pregnancy, labour and birth.
It is important to note that the study has not assessed the outcomes of women who were referred to obstetrics due to any pregnancy complications, having a multiple pregnancy, previous Caesarean, non-cephalic presentation (e.g. breech), or who went into premature labour, had prolonged rupture of membranes or who required induction. Women who remained under midwife care (either at home or in hospital) but who were considered to have medium, risk factors, such as history of postpartum haemorrhage were also excluded.
Additionally, as the extracted data relies upon the accuracy of recording all outcomes within national databases there may be some error in data entry or missed information, but within the study paediatric data on intensive care admissions was missing for 50% of non-teaching hospitals. Due to this method of assessment, it is also difficult to answer questions relevant to many home births, such as outcomes if complications were to develop, e.g. transportation times to hospital and time-delay prior to receiving expert obstetrician or neonatal care.
It should be noted that this study has assessed the situation over a seven-year period in the Netherlands only. These findings may not be representative of other countries and populations.
The safety of home births has often been debated but they offer an alternative to many women who would prefer to be surrounded by the comforts of home during labour and birth rather than the more clinical atmosphere of a hospital. However, as the authors of this study appropriately conclude, such a system relies upon a good maternity care system that allows pregnant women the choice of where they give birth through the availability of well-trained midwives, and through a good transportation and referral system to secondary care where necessary.