Supernumerary Blastocyst Cryopreservation: A key Prognostic Indicator for Patients Opting for an Elective Single Blastocyst Transfer (eSBT)

Objective

To determine if patients, less than 40 years of age with or without day 5 cryopreservation (d5 cryo), compromise their pregnancy rate (PR) by choosing an eSBT.

Design

Retrospective analysis

Setting

University IVF center

Patients

2,203 non-donor fresh IVF cycles in women <40 years of age from January 2004 to January 2010.

Interventions

None

Main outcome measure(s)

Eggs retrieved, Embryos cryopreserved, Implantation Rates, Clinical Pregnancy Rates, Live Birth Rates, Spontaneous Abortion Rates

Results

Pregnancy outcomes in women <40 years with or without d5 cryo were compared according to whether patients underwent an eSBT versus a 2BT in non-donor fresh IVF cycles. Overall, eSBT was associated with elimination of twinning while maintaining a high clinical pregnancy rate in both groups with d5 cryo (75 % eSBT versus 72 % 2BT) and groups without d5 cryo (48 % eSBT versus 56 % 2BT).

Conclusions

In this study, patients <40 years of age have eliminated twinning by electively choosing to transfer a single blastocyst without compromising their PR if embryos are available for d5 cryo, and suffer only a non-statistically significant drop in their PR if there are no embryos available for d5 cryo in exchange for the benefit of eliminating the obstetrical risk of twinning.