Pregnancy reduction in Jewish law

10% of infertile women who become pregnant with the aid of hormonal stimulation become pregnant with multiple fetuses. 20% of mothers of triplets experience preeclampsia and 35% risk serious postpartum hemorrhage. Risk increases with the number of fetuses for venous stasis, varicose veins, phlebothrombosis, thrombophlebitis, and embolic phenomena. Risk increases proportionally with increased number of fetuses for fetal morbidity and mortality. Selective abortion is often used as a method of reducing risk to both the woman and the fetuses, thus increasing the chance that 1 or 2 fetuses will be born healthy. A related issue is the selective reduction of fetuses in multiple pregnancies that may have a genetic defect like Hurler's syndrome, microcephaly, Tay-Sachs disease, spina bifida, hemophilia A, or thalassemia major. In cases where 1 fetus in a set of twins is so inclined, the reduction of the defective fetus increased the success of the remaining co-twin. Selective reduction should not pose a problem for Jewish women since the procedure does not violate any Jewish legal or moral rules. In Jewish law an unborn fetus is not considered a person until it is born. Until the 40th day of pregnancy it is considered as 'mere fluid.' In order to stress the positive aspect of selective reduction it should be called "enhanced survival of multifetal pregnancies."