OBJECTIVETo evaluate the effect of elevated basal follicle-stimulating hormone (FSH) on both the quantity and quality of oocytes and embryos and the clinical outcomes of pregnancy in women under 35 years of age.

METHODSA retrospective analysis was conducted for inspecting 294 in vitro fertilization-embryo transfer (IVF-ET) cycles in women under 35 years of age. According to the basal FSH levels, the women were divided into groups A, B, and C with basal FSH of 10-14.99, 15-19.99 and ≥20 IU/L, respectively, to compare the average number of oocytes retrieved, morphologies of the oocytes and embryos, and clinical outcomes of pregnancy.

RESULTSGroup A showed greater average numbers of oocytes collected, total embryos and good-quality embryos with a lower gonadotrophin dose required to achieve follicular maturity than groups B and C. The 3 groups showed no significant differences in the percentage of metaphase II oocytes, optimal embryos-blastomere number, normal fertilization rate, cleavage rate, good-quality embryo rate, implantation rate, pregnancy rates, live birth rate or miscarriage rate, but the pregnancy rates and live birth rate tended to decrease in women with basal FSH ≥15 U/L.

CONCLUSIONIn women below 35 years of age, an elevated serum FSH (especially one ≥15 U/L) indicates diminished ovarian reserve and reduced numbers of oocyte and embryo but not poor oocyte or embryos quality, and good clinical pregnancy rate can still be expected.