RESUMO
OBJECTIVE: To evaluate whether the basal serum luteinizing hormone (LH) levels in the presence of normal serum follicle stimulating hormone (FSH) are useful as a prognostic indicator of ovarian response to controlled ovarian hyperstimulation (COH). METHODS: From January 1997 to January 1999, 91 infertile women with tubal factor who had undergone in vitro fertilization and embryo transfer (IVF-ET) were enrolled in the present study. COH was performed using long protocol of gonadotropin-releasing hormone (GnRH) agonist. All patients included in this study had blood samples drawn on cycle day 2 or 3 prior to COH for measurement of basal FSH and LH. Women who had other infertility factors or high basal FSH levels (> or = 8.5 mIU/ml) were excluded from this study. The results of COH and IVF-ET were compared between two groups according to the level of basal LH (low LH group [ or = 3mIU/ml]). RESULTS: Patient's characteristics were comparable in both groups except basal LH level. The number of ampules and duration of exogenous gonadotropins required were significantly higher in the low LH group than those in the control group (p or = 14mm diameter on the day of human chorionic gonadotropin (hCG) injection was significantly less in the low LH group than that in the control group (p<0.001). The serum estradiol level on the day of hCG injection was also significantly lower in the low LH group, with 1115.5 +/- 380.9 pg/ml compared with 1340.6 +/- 403.0 pg/ml in the control group (p<0.005). There were significantly lower numbers in oocytes retrieved, oocytes fertilized and embryos frozen in the low LH group than those in the control group (< 0.001; < 0.001; <0.005, respectively). However, there was no difference in the fertilization rate between the two groups. The clinical pregnancy rate per cycle seemed to be lower in the low LH group, but the difference did not achieve significance (26.2% vs 39.7%). There were no differences in the miscarriage rate and multiple pregnancy rate between the two groups. CONCLUSION: This study demonstrates that the low basal LH levels ( < 3 mIU/ml) could be predictive of low ovarian response to COH and poor IVF results.