Outcome of pregnancy after in vitro fertilization

Abstract

In 2004 clinical pregnancy rates per aspiration and per transfer after in vitro fertilization (IVF) in Europe were 26.6% and 30.1%, respectively. The distribution of singleton, twin and triplet deliveries after IVF was 77.2%, 21.7% and 1%, respectively. The reported total multiple delivery rate of 22.7% during 2004 decreased, compared with 23.1% in 2003 and 24.5% in 2002. The proportion of children born after IVF ranged from 0.2% to 6.2% of all infants. Conceptions by IVF are associated with an increased incidence of several obstetrical and perinatal complications. Most of these complications are related to the high incidence of multiple gestations. However, even singleton pregnancies appear to be affected. Neonatal complications are primarly the result of preterm deliveries. Patients should be informed about the fact that pregnancies conceived by IVF are associated with increased risk of multiple gestations, preterm delivery, low birth weight, and complications associated with these outcomes. Several strategies attempting to control the frequency of high order multiples have been implemented. The overriding aim of the strategies is to transfer fewer embryos of higher quality to maximize the pregnancy rate and to minimize the risk of high order multiple gestation.