Elective cryopreservation of all embryos with subsequent cryothaw embryo transfer in patients at risk for ovarian hyperstimulation syndrome reduces the risk of adverse obstetric outcomes A preliminary study

Interval transfer of cryopreserved embryos derived from prior in vitro fertilization stimulation with elevated peak estradiol level reduces the risk of adverse obstetric outcomes.

Anthony N. Imudia, M.D., Awoniyi O. Awonuga, M.D., Anjali J. Kaimal, M.D., M.A., Diane L. Wright, Ph.D., Aaron K. Styer, M.D., Thomas L. Toth, M.D.

Volume 99, Issue 1, Pages 168-173, January 2013


To test the hypothesis that patients who undergo elective cryopreservation of all embryos (ECAE) due to risk of OHSS and elevated peak serum estradiol (EPE2), previously defined as level >3450 pg/mL (90th percentile) during IVF will be less likely to have small for gestational (SGA) infants and preeclampsia (PreE) as compared to patients with EPE2 that undergo fresh embryo transfer (ET).

Cohort study.

Tertiary care academic medical center.

Twenty patients who underwent ECAE with subsequent cryothaw embryo transfer (CET) and 32 similar patients with EPE2 during COH for IVF who underwent a fresh ET.


Main Outcomes:
Prevalence of SGA infants and development of preeclampsia in patients with cryothaw ET or fresh ET in the setting of elevated peak E2.

After adjusting for confounders (body mass index, antral follicle count, peak serum E2 level) using forward stepwise logistic regression, the patients who elected cryopreservation of all embryos and subsequent cryothaw ET were statistically significantly less likely to deliver SGA infants as compared with the patients who had fresh ET in the setting of elevated peak E2. In the entire cohort, a total of seven women had preeclampsia, all of whom had had fresh ET in the setting of elevated peak serum E2: 7 (21.9%) in the fresh ET group versus 0 women in the elective cryopreservation group.

This preliminary study suggests that elective cryopreservation of all embryos in patients with elevated peak serum E2 for subsequent cryothaw ET in cycles with a better physiologic hormonal milieu may reduce the odds of SGA and preeclampsia in IVF singleton deliveries.

  • Great article! We do a good amount of cryo-all cycles for patients at risk for OHSS. It’s interesting that there may be long term benefits in pregnancy to this as well. We generally trigger with lupron in this setting. Here, it looks like the trigger was hCG in both groups. I was just curious if that was true or what you generally use as a trigger if not?

    • Anthony N. Imudia

      Yes you are correct, the hCG triggers were with hCG. The dose was 5K IU instead of 10K.

Translate »