Increased risk for preterm delivery with IVF versus ICSI
MedWire News: The risk for a preterm delivery is significantly higher with IVF compared with ICSI, shows an analysis of population-wide Norwegian birth data.
Previous studies have revealed higher rates of preterm birth among women who conceive via assisted reproductive technology (ART) compared with spontaneous conception, but differences between specific ART methods have not been assessed, says Nils-Halvdan Morken, from Haukeland University in Bergen.
Morken evaluated preterm delivery risk in 4,886 ART-conceived singleton pregnancies (IVF = 2,985, ICSI = 1,901) identified in the Medical Birth Registry of Norway during 1999 through 2006. Of these, 479 were preterm (22 weeks to 36 weeks plus 6 days).
There were no characteristic differences between the IVF and the ICSI cohort, aside from more mothers aged at least 35 years, more mothers with a parity of 3, more regular smokers, and more male fetuses in the IVF group.
There were similar rates of spontaneous preterm delivery among the IVF and ICSI groups.
However, after adjusting for fetal sex, small for gestational age, maternal age, smoking, and parity, the risk for moderately (32-36 weeks) iatrogenic preterm delivery was a significant 60 percent greater among IVF-treated women then ICSI-treated women,
"The current study shows the importance of assessing preterm delivery risk for both the different [ART] subgroups and in different gestational age categories of this complex and heterogeneous entity," concluded Morken.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
By Sarah Guy