DOES THE INTERVAL TIME BETWEEN OVULATION TRIGGERING AND OOCYTE PICK UP AFFECT BIOLOGICAL RESULTS IN LOW, NORMAL AND HIGH OVARIAN STIMULATION RESPONDERS ?

Abstract

To assess the effect of time interval between ovulation triggering (OT) and oocyte pick up (OP) on biological results in low, normal and high responders A prospective observational study performed in the department of Reproductive Medicine in Aziza Othmana Hospital between January and December 2019. Inclusion criteria : age between 18 and 42 years old. Controlled ovarian stimulation with antagonist protocol for ICSI. Exclusion criteria: Mild ovarian stimulation / ovulation triggering by GnRH agonist (OHSS prevention) We divided patient into poor, normal and high ovarian responders (based on AMH and AFC) The ovarian stimulation was performed with an antagonist protocol for all patient with recombinant FSH (Gonal F, Merck) and cetrorelix acetate (Cetrotide, Merck). The ovulation triggering was performed when 2 or more follicles reached 17 mm with recombinant HCG (Ovitrelle 250, Merck). The interval time between OT and OP was divided into 4 groups: 35 h (group 1), 36 h (group 2) , 37 h (group 3) and ≥ 38 h (group 4). χ2 test was used to compare qualitative variables. Student’s t-test was used to compare quantitative variables. P-value < 0.05 was considered as statistically significant. Five hundred and eighty four patients were included: 204 poor responders, 310 normal responders and 70 high responders group. For poor ovarian responders, we did not find a statistical difference for the number of oocyte retrieved (5.8 ; 3.3 ; 3.7 ; 3.6 ; p=0,2) the number of MII (3.8 ; 2.1; 2.4 ; 2.6 ; p=0,2) and the ratio MII/CCO: (0.65 ; 0.63 ; 0.66 ; 0.7é ; p=0,06) in the group 1, 2, 3 and 4 respectively. For normal ovarian responders, we did not find a statistical difference for the number of oocyte retrieved: (7.7 ; 8.8 ; 8.1 ; 8.5 ; p=0,8) ; the number of MII: (5.2 ; 5.9 ; 5.6 ; 5.5 ; p=0,9) and the ratio MII/CCO (0.67 ; 0,67 ; 0.69 ; 0.64 ;p=0,3) in the group 1, 2, 3 and 4 respectively. For high ovarian responders, we did not find a statistical difference for the number of oocyte retrieved (22 ; 18 ; 17 ; 23 ; p=0,3); the number of MII (16 ; 11,9 ; 12,1 ; 14 ; p=0,8) and the ratio MII/CCO (0.72 ; 0.66 ; 0,71 ; 0.6 ; p= 0,1) in the group 1, 2, 3 and 4 respectively. It is not certain that adjustment of the interval time between OT and OP is necessary according to different ovarian responders in order to improve the IVF output. Moreover; studies are needed to determine if these results are applicable when using a GnRH agonist ovarian stimulation protocol.