<<Print>>

Several drugs often given during labor reduce breastfeeding rates, say researchers from the UK in the November BJOG: An International Journal of Obstetrics and Gynaecology. On the other hand, inhaled nitrous oxide during labor appears to increase breastfeeding rates in primiparous women, according to Dr. Susan Jordan from Swansea University and colleagues. The study findings "suggest where additional support to mothers wishing to breastfeed might be usefully targeted," Dr. Jordan told Reuters Health by email. "We should be very pleased if our findings could lead to further support being offered to women receiving ergometrine and multiple medications during labor." Dr. Jordan and her colleagues used Cardiff Births Survey data on 48,366 deliveries to explore the hypothesis that routine intrapartum medication is associated with reduced chances of breastfeeding by healthy singletons born to healthy mothers. At 48 hours after delivery, 43.3% of women were not breastfeeding, including 37.4% of primiparous women. After accounting for maternal age, parity, social class, and deprivation - all known to affect breastfeeding rates - the authors found that the results in this large cohort upheld previously described associations of breastfeeding with intramuscular opioids and epidurals. Oxytocin and ergometrine in the third stage of labor and prostaglandins for induction of labor were associated with significant reductions in breastfeeding rates between 6% and 8% at 48 hours, the researchers note. "Retrospective observational studies are useful for identifying associations and generating hypotheses, but confirmation of hypotheses needs more robust evidence such as randomized trials," writes Dr. A. Bhide from St. George's Hospital, London, in a related editorial. "A Cochrane review based on two randomized trials involving 3142 women did not detect any influence of uterotonic drugs on the rate of breastfeeding." Dr. Jordan said, "We fully concur with editorialists' statements that our findings, based solely on retrospective analyses, are insufficient grounds to change established prescribing practices: indeed, in the discussion, we make this a central recommendation of our paper." She added, "We are seeking collaborators for a randomized controlled trial of medicated and unmedicated third stage of labor, involving low risk women. We are also hoping that other large databases will be available for analysis."