PLOD1 and polycystic ovary syndrome: Wang et al. (2016) conducted a randomized controlled trial (RCT) and showed that the use of MPA in the ovarian stimulation cycle can be effective and feasible without worsening pregnancy outcomes, and with a low incidence of ovarian hyperstimulation syndrome (OHSS) in women with polycystic ovary syndrome (PCOS). Iwami et al. (2018) and Yu et al. (2018) demonstrated that dydrogesterone could be used as a progestogen alternative for blocking the LH peak in IVF cycles, the latest being an RCT.