Cumulative live birth rates after transfer of cryopreserved ICSI embryos

A cohort follow-up study was designed to assess the efficacy of an intracytoplasmic sperm injection cryopreservation programme through analysis of cumulative live birth rates in successive frozen-thawed cycles in a tertiary referral centre. There were 2013 patients and they underwent 2680 frozen-thawed embryo transfer cycles. The follow-up period was between 1992 and 2001. Only frozen-thawed embryo transfer cycles up to the fourth trial were included. Crude cumulative live birth rates were calculated in five age subgroups, i.e. <30, 30-34, 35-37, 38-39 and >/=40 years old and in surgically or non-surgically retrieved sperm subgroups. Expected cumulative live birth rates were calculated only for the total number of patients. Outcome measure was a live birth occurring after 25 weeks of gestation. Overall, the expected cumulative live birth rate was as high as 26.7% after four cycles while the crude cumulative delivery rate was 10.5%. Multiple cryopreserved embryo transfer cycles increase the chance of a couple to achieve a live birth.