Are adverse outcomes of IVF the same as spontaneous conception?

Babies conceived spontaneously and as a result of assisted fertilization by the same woman have similar risks of adverse outcomes, meaning that adverse outcomes among assisted fertilization babies may be attributable to the underlying causes of infertility rather than the fertility treatment itself, according to a report published online July 31 in The Lancet.

Liv Bente Romundstad, MD, of St. Olav's University Hospital in Trondheim, Norway, and colleagues conducted a study of singleton babies born to 2,546 Norwegian women who had conceived at least one child spontaneously and another after assisted fertilization. The cohort was drawn from 1,200,922 births after spontaneous fertilization and 8,229 after assisted fertilization.

Among siblings, the difference in mean birthweight between babies conceived spontaneously and those conceived using assisted fertilization was only 9 g, and there was a mean 0.6 day’s difference in duration of gestation, the researchers report. There was no difference between the two groups of babies in terms of risk of being small for gestational age or for preterm delivery.

“The adverse outcomes of assisted fertilization that we recorded in comparisons with spontaneous pregnancies in the general population could therefore be caused by the underlying infertility, rather than to factors related to the reproductive technology,” the authors conclude.

Romundstad

LB,

Romundstad

PR,

Sunde

A, et al. Effects of technology or maternal factors on perinatal outcome after assisted fertilisation: a population-based cohort study.

Lancet

. 2008, published online at DOI:10.1016/S0140-6736(08)61041-7