Efficacies of different ovarian hyperstimulation protocols in elderly patients with poor ovarian response

The aim of the study was to explore which controlled ovarian hyperstimulation (COH) protocol is most suitable for elderly patients with poor ovarian response (POR) undergoing assisted reproductive technology (ART).

This retrospective cohort study evaluated clinical data from 2,660 patients from January 2017 and October 2020. The patients were divided into three groups: modified Gonadotropin-releasing hormone (GnRH) agonist protocol (1,225 patients), GnRH antagonist protocol (1,038 patients), and Mild stimulation protocol (397 patients). Clinical variables and pregnancy outcomes were compared among the three groups.

The GnRH agonist protocol was associated with a higher number of oocyte number (3.99±2.82 vs. 3.02±1.34 vs. 2.51±1.14, p<0.001), a higher number of transferable embryos (1.39±1.32 vs. 1.24±1.24 vs. 1.18±1.11, p = 0.035), higher cumulative live birth rate [26.53% (323/1,225) vs. 22.44% (233/1,038) vs. 21.66% (86/397), p = 0.043], lower OHSS rate [5.14% (63/1,225) vs. 3.08% (32/1,038) vs. 2.02% (8/397), p = 0.005] than GnRH antagonist protocol and Mild stimulation protocol, the Mild stimulation protocol was associated with higher miscarriage rates [30.4% (24/71) vs. 25.0% (33/192) vs. 29.6% (35/168), p = 0.014] than the other two groups.

The three protocols can be used in elderly patients with POR; however, if patients require more frozen-thawed embryo transfers to achieve better cumulative live birth rates, the modified GnRH agonist protocol may be the better choice. It should be emphasized that the mild stimulation had a slightly higher miscarriage rate than the other two groups.