Optimal timing for elective egg freezing

Abstract

Objective: To estimate the optimal age to pursue elective oocyte cryopreservation.

Design: A decision-tree model was constructed to determine the success and cost-effectiveness of oocyte preservation versus no action when considered at ages 25-40 years, assuming an attempt at procreation 3, 5, or 7 years after initial decision.

Setting: Not applicable.

Patient(s): Hypothetical patients 25-40 years old presenting to discuss elective oocyte cryopreservation.

Intervention(s): Decision to cryopreserve oocytes from age 25 years to age 40 years versus taking no action.

Main outcome and measure(s): Probability of live birth after initial decision whether or not to cryopreserve oocytes.

Result(s): Oocyte cryopreservation provided the greatest improvement in probability of live birth compared with no action (51.6% vs. 21.9%) when performed at age 37 years. The highest probability of live birth was seen when oocyte cryopreservation was performed at ages <34 years (>74%), although little benefit over no action was seen at ages 25-30 years (2.6%-7.1% increase). Oocyte cryopreservation was most cost-effective at age 37 years, at $28,759 per each additional live birth in the oocyte cryopreservation group. When the probability of marriage was included, oocyte cryopreservation resulted in little improvement in live birth rates.

Conclusion(s): Oocyte cryopreservation can be of great benefit to specific women and has the highest chance of success when performed at an earlier age. At age 37 years, oocyte cryopreservation has the largest benefit over no action and is most cost-effective.

Keywords: Elective oocyte cryopreservation; egg freezing; fertility preservation.

Figure 1. Simplified decision tree for Model A

For a simplified representation of the decision tree, chance nodes for probability of 2^nd and 3^rd cycles from frozen oocytes, 1^st and 2^nd FET, and miscarriage were not shown. Analysis was repeated for Decision Age between 25 and 40 years, assuming a 7-year time horizon before attempting pregnancy. In Model A (requires marriage to attempt conception), those who did not marry did not attempt pregnancy. In Model B, all women attempt pregnancy, either with a partner or with donor sperm. ■Denotes decision node ○Denotes chance node

Figure 2

The Y-axis represents the probability of live birth at Horizon Age, which is 7 years after Decision Age. Decision Age is presented on the X-axis. Solid line: cryopreserving oocytes (OC). Dashed line: no action. Model A represents women requiring marriage prior to attempting pregnancy. Model B represents women who do not require marriage prior to attempting pregnancy (will attempt pregnancy with husband, donor sperm, or unmarried male partner).

Figure 3

Cost per additional live birth at Horizon Age when electing to cryopreserve oocytes versus no action at Decision Age, which is presented on the X-axis. Model A represents women requiring marriage prior to attempting pregnancy. Model B represents women who do not require marriage prior to attempting pregnancy (will attempt pregnancy with husband, donor sperm or unmarried male partner).