The influence of body mass index, basal FSH and age on the response to gonadotrophin stimulation in non-polycystic ovarian syndrome patients

BACKGROUND: Adequate ovarian response to exogenous gonadotrophins is important for both ovulation induction (OI) and controlled ovarian stimulation (COS). The objective of this study was to analyse the effect of a number of clinical factors that influence ovarian response in non-polycystic ovarian syndrome (non-PCOS) patients. METHODS: A total of 140 OI cycles (52 subjects), where each subject had a single abnormality (elevated FSH, abnormal body mass index (BMI) or greater than or equal to40 years of age), were compared with 54 cycles (15 subjects) where the patients displayed none of these abnormal features (the normal group). Similarly, 275 COS cycles (135 subjects), where each subject displayed a single abnormality, were compared with 79 cycles (40 subjects) in the normal group. RESULTS: For OI, subjects with a high basal FSH generally had an inadequate response with a poor chance of conception. Subjects with an abnormal BMI commonly required dosage adjustment so were more difficult to manage. Their potential for conception was normal. Older women seemed to respond normally with a normal expectation of conception. In the COS group, subjects with a moderately high basal FSH responded and conceived normally. Subjects with an abnormal BMI had an increased risk of an inadequate response leading to cancellation but if the response was adequate then the outlook was good. Older women required more gonadotrophin with a poor response and a low chance of conception. CONCLUSION: The results have better defined the anticipated responses of non-PCOS patients to gonadotrophin stimulation in both OI and COS.