Births in Israel resulting from in-vitro fertilization/embryo transfer, 1982-1989: National registry of the israeli association for fertility research

Our objective was to describe the characteristics of pregnancies, deliveries and children at birth following in-vitro fertilization (IVF) and related technologies in Israel, from 1982 to 1989. A national survey with collaboration from all IVF units in the public hospitals was designed and data were collected on individual patients. Comparison of results was made with data from a national delivery census and from other national IVF registries. During the period covering this survey, 1149 deliveries resulted in 1475 newborns; 98% of deliveries occurred following conventional IVF and embryo transfer (IVF-ET), 2% after in-vivo fertilization and gamete intra-Fallopian transfer. Following IVF-ET, 23% of the pregnant women were hospitalized due to a complication of pregnancy and 47.3% of the deliveries were by Caesarean section (41% if multiple births are omitted). The male to female birth ratio was 1.07: 1.0; 23.6% of the deliveries were multiple births, 28.6% of deliveries were pre-term and the median length of gestation decreased with multiple births. At delivery, 23.8% of newborns weighed <2500 g. The incidence of low birthweight newborns was significantly higher in multiple births. The ratio of perinatal mortality (22.8/1000), double the incidence found in a national census (13/1000), increased dramatically with multiple births (12.7, 24.5 and 75.8/1000 for singleton, twins and triplets respectively). The incidence of a major congenital malformation was 2.2%, no higher than in the general population. A survey of published national IVF registries from Australia and New Zealand, Great Britain, USA and France showed much similarity in all aspects of pregnancy outcome following IVF and related technologies. The main complication following conception with assisted reproductive technology was multiple pregnancy, which was the main factor related to adverse outcomes in terms of gestational length, birthweight and perinatal mortality. Measures should be taken to decrease the incidence of multiple pregnancies. The rate of congenital; malformations was not increased and reassurance can be given to patients based on worldwide results. Pooling of data from all national registries is recommended to increase the study size and the significance of results.