Efficacy and safety of Dingkun pill for female infertility patients with low prognosis undergoing in vitro fertilization-embryo transfer: study protocol for a multicenter, double-blind, randomized, placebo-controlled trial

Approximately 15% of couples in the reproductive age are affected by infertility. Women with diminished ovarian reserves (DOR) or with a poor ovarian response (POR) are required to undergo in vitro fertilizati…