In a small study of 21 young women undergoing egg donation cycles, using a vaginal progesterone spray every 12 hours worked just as well as taking oral dydrogesterone to stop the body from releasing an early LH surge before egg retrieval. Both groups had similar numbers of follicles and mature eggs, and none got ovarian hyperstimulation syndrome after the GnRH‑agonist trigger (triptorelin).

A new approach to evaluate whether Progestin-Primed Ovarian Stimulation with micronized vaginal progesterone was as effective as using dydrogesterone in suppress LH pulse surge in young women under stimulation in an oocyte donor programme. This prospective study included 21 patients aged 19 to 32 years-old stimulated with Elonva® 150, associated or not with Menopur® or Merional® (75 or 150IU) since the beginning of the cycle, plus HMG 150-225IU after the 8th day or just HMG 150-300IU per day. Patients were placed in a PPOS protocol with micronized vaginal progesterone (MVP) 200 mg (Gynpro® Exeltis or Junno Farmoquimica) every 12 hours or dydrogesterone (Duphaston® Abbott) 10 mg every 8 hours from the start of stimulation until the day after the GnRH trigger with Triptorelin 0.2 mg (Gonapeptyl daily®). The primary endpoint was the prevention of untimely LH surge, and secondarily the number of 16 mm follicles, retrieved oocytes and metafase II. Fourteen oocyte donor patients were prescribed MVP while seven others received dydrogesterone (DYG).The gonadotropin protocols included 04 with Corifollitropin alfa 150 plus HMG since the beginning and complemented after the 7th day, and 17 times of just HMG. There was no diferences in the number of follicles >10≤15mm, ≥16mm or number of metafase II oocytes. There was no untimely LH surge on both groups and no OHSS was developed after the agonist trigger. Progestin-Primed Ovarian Stimulation with micronized vaginal progesterone seems to be a compelling choice for preventing premature ovulation without compromising oocyte quality in women undergoing ovarian stimulation.