Attachment of a trophoblastic spheroid onto endometrial epithelial cells predicts cumulative live birth in women aged 35 and older.

OBJECTIVE: To evaluate the attachment rate of a human embryonic stem cell-derived trophoblastic spheroid onto endometrial epithelial cells in predicting the cumulative live birth rate of an in vitro fertilization (IVF) cycle.

DESIGN: A prospective observational study.

SETTING: University hospital and research laboratory.

PATIENT(S): A total of 240 infertile women from 2017-2021.

INTERVENTION(S): Infertile women with regular cycles attending for IVF were recruited. An endometrial aspirate was collected from a natural cycle 1 month before IVF to determine the BAP-EB attachment rate.

MAIN OUTCOME MEASURE(S): Cumulative live birth rates from a stimulated cycle and its derived frozen embryo transfer cycles within 6 months of ovarian stimulation were obtained.

RESULT(S): The BAP-EB attachment rate in women who attained a cumulative live birth was similar to that in those who did not. When women were stratified by age into <35 years and ≥35 years, the BAP-EB attachment rate was significantly higher only in women aged ≥35 years having a live birth when compared with those in the same age group without a live birth. Receiver operating characteristic curve analysis of BAP-EB attachment rate in predicting cumulative live birth showed the areas under the curve of 0.559 (95% confidence interval [CI], 0.479-0.639), 0.448 (95% CI, 0.310-0.585), and 0.613 (95% CI, 0.517-0.710) for all ages, an age of <35 years, and an age of ≥35 years, respectively.

CONCLUSION(S): The BAP-EB attachment rate offers only a very modest prediction of the cumulative live birth rate in women aged ≥35 years undergoing IVF.

CLINICAL TRIAL REGISTRATION NUMBER: NCT02713854 (https://clinicaltrials.gov/ct2/show/NCT02713854; Date of registration, March 21, 2016; date of enrollment of the first subject, August 1, 2017).