Prospective cohort.
Private practice.
Women undergoing fresh ART cycles (n = 209).
In vitro fertilization using standard protocols. Embryos scoring GES of ≥70 using were selected for transfer on the basis of sHLA-G expression in the culture media on day 2.
Pregnancy, implantation, and multiple-gestation rates.
Ongoing gestations increased with the number of embryos expressing sHLA-G (37 % , 42 % , 58 % , and 56 % with 0, 1, 2, or 3 sHLA-G+, respectively). With at least two sHLA-G+ embryos, ongoing gestation and implantation rates were higher than those with fewer than two sHLA-G+. Differences were even higher for women aged ≤37 years. With at least two sHLA-G+ embryos, the odds ratio (95 % confidence interval) was 1.59 (1.51–1.68) for ongoing gestation compared with the case of fewer than two sHLA-G+. Age was the most important predictor of outcome; the odds ratio (95 % confidence interval) was 2.07 (1.98–2.16) for ongoing gestation in women aged ≤37 years with at least two sHLA-G+ embryos, compared with the case of women aged 38–40 years.
Day 3 embryo transfer using GES and sHLA-G improves ART outcomes by increasing predictive accuracy. High twin rates suggest that couples with at least two sHLA-G+ embryos consider elective single-embryo transfer.