P–704 Does the type of ovarian stimulation scheme and dose matter when calculating the amount of gonadotropins used to obtain an egg?

Abstract

Abstract Study question Is the controlled ovarian stimulation protocol important to determine the ovarian sensitivity index (number of oocytes retrieved / total gonadotropin dose)? Summary answer OSI in an interesting tool in estimating the ovarian sensitivity to exogenous gonadotropins and can be adjusted when different kinds of COS procotols are used. What is known already In our country, Argentina, as the fertility treatments are financed by different health care insurance companies, COS protocols may vary depending on the drugs provided. The objective of our study is to assess the oocyte retrieval number in patients undergoing COS, for IVF or fertility preservation (egg freezing), on the basis of the kind of protocol and the average gonadotropin dose. Study design, size, duration This is a retrospective and descriptive study in which 684 cycles, performed between November 2018 and March 2020, were evaluated. Patients underwent COS for IVF or fertility preservation purposes. Participants/materials, setting, methods COS protocols were analysed including different parameters such as: number of mature follicles (17mm or more) the trigger day, number of oocytes retrieved, number of M2 retrieved, follicle to oocyte index (FOI), and the kind of protocol.Each of these groups were divided into four groups depending on the protocol used. Group A: FSHr; Group B: FSHr/LHr; Group C: FSHr + HMG; Group D: Clomiphene citrate + HMG. Oocyte donors and incomplete medical records were excluded Main results and the role of chance The total number of cycles analysed was 684. There were 135(19.7%) cycles in the under 35 age group; 340(42%) in the 35 to 39 group; 209(38%) in the older than 40 group. They were subdivided in Group A: 54(6.67%) cycles; Group B 93(11.11%) cycles; Group C 465(71.72%); Group D 72(10.5%). A total number of 11351 oocytes were retrieved, with a mean average of 4.6 +- 2.5 SD per patient. Assessment of dose of gonadotropin per oocyte retrieved in each different group: GROUP A 360IU+–38 SD; GROUP B 390IU+–43 SD; GROUP C 375IU +–44 SD; GROUP D 479+–36 SD. Limitations, reasons for caution This is a retrospective study. Further prospective studies and a higher sample size are needed to confirm whether the OSI is a useful tool to adjust gonadotropins doses related to an specific COS protocol and improve the oocyte pick up. Wider implications of the findings: The main conclusion obtained was that the average dose of gonadotropin needed to obtain one mature oocyte was 360 to 390 IU. The HMG and clomiphene citrate protocol needed the highest dose of gonadotropin (479 IU) but no significant stadistical differences were observed. Trial registration number NA