Beyond the American Society for Reproductive Medicine transfer guidelines: how many cleavage-stage embryos are safe to transfer in women ≥43 years old?

OBJECTIVE

To determine the number of cleavage-stage embryos that can be safely transferred in women ≥43 years old.

DESIGN

Retrospective cohort.

SETTING

Academic medical center.

PATIENT(S): All patients ≥43 years old undergoing transfer of five or more cleavage-stage embryos during the period from January 2004 through April 2012.

INTERVENTION(S): In vitro fertilization.

MAIN OUTCOME MEASURE(S): A total of 567 cycles in 464 patients aged 43-45 years, whose IVF cycles were characterized by transfer of five to eight cleavage-stage embryos were identified. Clinical outcomes and risk of multiples were analyzed, stratifying by age and number of embryos transferred.

RESULT(S): Live birth rates per transfer were 14.4%, 9.4%, and 1.3% for women aged 43, 44, and 45 years, respectively. In 43-year-old women, 2.9% (2/69) of pregnancies were triplet gestations (one selective reduction and one spontaneous reduction). Twin birth rate was 16.3%, 6.7%, and 0 (of all live births) for ages 43, 44, and 45 years, respectively. There was no higher order multiple births. Women aged 43 and 44 years having five or more embryos transferred experienced higher clinical pregnancy rates (PRs) than those patients receiving a transfer of three or four embryos. Clinical outcomes for patients undergoing transfer with six or more embryos were not better than those undergoing transfer with five embryos.

CONCLUSION(S): Transferring five or more day 3 embryos may be a safe option for patients ≥43 years of age, as it is associated with an overall low rate of multiple gestations. Having more than five embryos available for transfer on day 5 is associated with improved IVF outcomes. Whether this benefit is from the additional embryo(s) for transfer or the inherently better prognosis of such patients remains to be determined.