Poor responders to ovulation induction: is proceeding to in-vitro fertilization worthwhile?

A 'poor response' in the context of in-vitro fertilization (IVF) can be defined as failure to produce an adequate number of mature follicles, and/or a peak oestradiol concentration less than a defined minimum. The cut-off points implied in this definition vary between different centres. Many opt to cancel the IVF cycle when their defined minimum concentrations are not reached despite the lack of evidence of improved outcome in subsequent cycles. Patients attending the Oxford Fertility Unit who are 'poor responders' have always been given the option of continuing with treatment. The first cycles of IVF in 124 patients, with normal day 3 follicle stimulating hormone (FSH), who produced less than five follicles within a 2 year period were studied. The patients were divided into three groups according to the number of follicles produced: A (one or two follicles; n = 33), B (three follicles; n = 33) and C (four follicles; n = 58). The three groups were similar in age, day 3 FSH, total gonadotrophin dose, duration of stimulation, peak oestradiol concentration, oocyte yield, fertilization rate and the clinical pregnancy rate. However, group A had a significantly higher oestradiol concentration per follicle (P < 0.001). The clinical pregnancy rate/cycle in the three groups was comparable to our overall rate in the study period (25.5%). This paper suggests that poor responders with a normal day 3 FSH may still achieve a pregnancy rate similar to that of normal responders.