Risk of multiple birth associated with in vitro fertilization using donor eggs

Multiple birth, which is associated with adverse fetal, infant, and materna l outcomes, is increasingly related to the use of in vitro fertilization (I VF). Among women undergoing IVF who use their own eggs, greater maternal ag e is associated with decreased risk of multiple birth; using donor eggs fro m younger women may negate this age effect. Data from 6,936 IVF procedures performed in the United States in 1996-1997 on women aged 35-54 years who u sed donor eggs were analyzed to assess the effect of maternal age, number o f embryos transferred, and cryopreservation of extra, nontransferred embryo s (an indicator of higher embryo quality) on risk of multiple birth. Greate r maternal age did not decrease multiple-birth risk. Rates of multiple birt h were related to number of embryos transferred and whether extra embryos h ad been cryopreserved, and they were high compared with those of IVF patien ts the same age who had used their own eggs. Among women who had extra embr yos cryopreserved, transferring more than two embryos increased multipte-bi rth risk, with no corresponding increase in the chance for a livebirth. The se results highlight the need to consider the age of the donor and embryo q uality when making embryo transfer decisions involving use of donor eggs.