DYDROGESTERONE AS AN ALTERNATIVE TO SUPPRESS LH SURGE IN ART CYCLES.

The aim of this study is to evaluate the effectiveness of Dydrogesterone in PPOS protocols for IVF/ICSI cycles or Oocyte cryopreservation both in blocking the LH surge as well as evaluate the number of metaphase II oocytes. 550 IVF/ICSI plus 186 oocyte cryopreservation cycles from January 2018 to December 2020, no age restriction. All patients were given Follitropin delta (Rekovelle®, Ferring Pharmaceuticals) or Menotropin (Menopur®, Ferring Pharmaceuticals) in a fixed daily SC dose. Clinical decision led to a GnRH antagonist (CTA-Cetrorelix acetate, Cetrotide®, Merck) 0,25 mg/d initiated in a flexible shedule in presence of one follicle ≥ 14 mm and continued throughout the stimulation period (326 cycles) or dydrogesterone (DYG), 10 mg 8/8 hs (Duphaston®, Abbott) combined to gonadotrophin from the beginning of stimulation until the day after the trigger (410 cycles). The final follicular maturation was performed when there were three or more follicles ≥ 17 mm diameter either with 250 mg recombinant hCG (Choriogonadotropin alfa, Ovidrel®, Merck) or GnRH agonist, 2 ampules (triptorelin acetate Gonapeptyl Daily®, Ferring Pharmaceuticals). Cancelling criteria: no follicles with a diameter 17 mm by day 15. Oocyte retrieval took place 36 hours after trigging. Primary outcome was the incidence of premature LH surge. Secondary outcomes included follicles ≥ 15 mm and < 18 mm and ≥ 18 mm on hCG day, metaphase II oocytes, number of cancelled cycles and OHSS symptoms. Statistics were performed by Mann-Whitney test. DYG group had a mean age significantly higher (37.13 x 37.81-p 0.02) but there were no differences in mean parameters of BMI (25.25 x 24.37), days of stimulation (10.03 x 10.15), AMH values (1.95 x 1.90), AFC (12.47 x 12.29). Differently, differences were observed between follicles 15 mm to 18 mm (3.04 x 2.65-p 0.02) and ≥ 18 mm (3.72 x 4.67), with a tendency for a greater number of larger follicles in the DYG group. Metaphase II oocytes (6.57 x 6.86) was similar in both groups. No patient from either group experienced a premature LH surge (3.08 x 3.64) and one case in the DYG group had no oocyte in a single 20 mm aspirated follicle. There happened no cancelling. No patients experienced moderate to severe ovarian hyperestimulation syndrome, even when AMH > 3 ng/mL. Dydrogesterone is an eligible tool to IVF/ICSI cycles intended to freeze-all / PGT-A and oocyte preservation. It can also be considered either to embryo banking or preventing OHSS in higher AMH patients