The impact of single embryo transfer policy on pregnancy outcomes after legislative change

We evaluated the effect of mandatory single embryo transfer (SET) on live birth rates and pregnancy outcomes in Turkey. A retrospective study was conducted in Zekai Tahir Burak Women's Health Education and Research Hospital. Four hundred and four patients undergoing intracytoplasmic sperm injection (ICSI) cycles were included in the study. In Turkey, the number of embryos to be transferred in an assisted cycle was limited to three under normal circumstances until 6 March 2010. After that, new legislation was introduced to promote the application of SET. Outcomes were compared in periods of 1 year before and after the new law. We compared pregnancy outcomes of all assisted reproductive cycles in SET cycles (group 1: n = 281) with double embryo transfer (DET) cycles (group 2: n = 123). There were significant differences in oocyte number, multiple pregnancy, gestational age, birth weight and perinatal fetal morbidity between the groups (p = 0.023, 0.001, 0.001, 0.001, 0.001, respectively). But there were no differences in age, baseline FSH, infertility period, stimulation protocol, stimulation day, gonadotrophin dose, clinical pregnancy rate, abortion rate, live birth rate and cesarean rate (p > 0.05). These results suggest that under the new legislation multiple pregnancy rates and perinatal complications are significantly reduced without causing a significant decline in the pregnancy rates.