The main ART outcome measures are as follows: number of oocytes retrieved, fertilization rate, implantation rate, clinical pregnancy rate per embryo transfer, embryo quality, miscarriage rate, and live birth rate.
At baseline, median female age was 34.1 years, waiting time 3 years (1-17), number of preceding miscarriages 3 (3-9), 147 women (20.4%) had conceived at least once in ART or AIH cycles.
Letrozole significantly decreases the risk of miscarriage and does not increase the risk of major congenital anomalies or adverse pregnancy or neonatal outcomes compared with natural cycles in patients undergoing ART.