Homebirth is a risk factor for meconium aspiration syndromeA new study on meconium aspiration syndrome found that homebirth is a risk factor. The Epidemiology of Meconium Aspiration Syndrome: Incidence, Risk Factors, Therapies, and Outcome by Dargaville and Copnell (PEDIATRICS Vol. 117 No. 5 May 2006, pp. 1712-1721) looked at "all of the infants in Australia and New Zealand who were intubated and mechanically ventilated with a primary diagnosis of MAS between 1995 and 2002, inclusive. Information on all of the live births during the same time period was obtained from perinatal data registries."
From the article:
Meconium aspiration syndrome (MAS) is a disease of the term and near-term infant that is associated with considerable respiratory morbidity. The disease is characterized by early onset of respiratory distress in a meconium-stained infant, with poor lung compliance and hypoxemia clinically and patchy opacification and hyperinflation radiographically. At least one third of infants with MAS require intubation and mechanical ventilation,..Among the findings:
In the past few decades, there seems to have been a reduction in the incidence of MAS in many centers, at least in the developed world... The apparent reduction in the risk of MAS has been attributed to better obstetric practices, in particular, avoidance of postmaturity and expeditious delivery where fetal distress has been noted.
We found that during the period 1995–2002, there was ... a strong association of MAS [requiring intubation] with low 5-minute Apgar score, a clear increase in risk in Pacific Islander and indigenous Australian pregnancies, and a similar association with advanced gestation to that noted previously. A heightened risk of MAS [requiring intubation] was also noted after planned home birth... Mortality directly attributable to MAS was 2.5% in the MAS [requiring intubation] cohort.The authors found that homebirth increased the risk of meconium aspiration syndrome requiring intubation by a factor of 2.7.
Why might homebirth be associated with an increased risk of this serious complication? Both increased gestational age and fetal distress are independent risk factors for meconium aspiration syndrome. Indeed, induction of labor and more aggressive managment of fetal distress were associated with a decrease in meconium aspiration syndrome requiring intubation over the course of the study. The refusal of postdates inductions and the inability to diagnose and manage fetal distress in a timely manner at home may be contributing to the increased risk of MAS requiring intubation posed by homebirth. This is not a trivial complication. The neonatal death rate in this group of infants was 25/1000 (2.5%).