The obstetrical and neonatal outcome of babies born after single-embryo transfer in IVF/ICSI compares favourably to spontaneously conceived babies.

BACKGROUND: Recently, concern has risen about poor obstetrical and neonatal outcome of singletons after IVF/ICSI. Because the population of patients receiving single-embryo transfer (SET) resulting in singleton pregnancies is different from the one that would have become pregnant (with a singleton) before SET was introduced, we wanted to investigate whether the outcome of singleton pregnancies after SET differed from spontaneously conceived singletons.
METHODS: The obstetrical and early neonatal outcome of all pregnancies originating from SET after IVF/ICSI procedures between 1 January 1998 and 31 December 2003, was prospectively collected and analyzed.
RESULTS: Data from 251 singleton pregnancies and births after SET were analyzed and compared to data from 59,535 spontaneously conceived singletons retrieved from the Centre for Perinatal Epidemiology. The mean birthweight of the singletons after SET was 3322 g (+/-538 SD) versus 3330 g (+/-531 SD) for the spontaneously conceived singletons (P = 0.82). The mean gestational age was 38.7 weeks (+/-1.9 SD) for SET and 38.9 weeks (+/-1.8 SD) for spontaneously conceived singletons (P = 0.06). The proportion of very preterm birth (<32 weeks) was 0.8% in each group, and the proportion of preterm birth (<37 weeks) was 10.0% for SET singletons and 6.24% for spontaneous singletons (P = 0.03). However, mean birthweight of very preterm, preterm and term SET singleton babies was similar to the mean birthweight in every category of gestational age in the spontaneous conceived control group. Stillbirth was 0.4% for both populations (P = 0.99).
CONCLUSIONS: Good prognosis patients, in whom SET is applied, do not only have a higher chance of conception but do not have an unfavourable outcome of their singleton baby when compared to spontaneous singletons.