THE SIGNIFICANCE OF ELEVATED EARLY FOLLICULAR-PHASE FOLLICLE-STIMULATING-HORMONE (FSH) LEVELS - OBSERVATIONS IN UNSTIMULATED IN-VITRO FERTILIZATION CYCLES

Objective: Our objective was to determine the effect of elevated early follicular-phase serum follicle stimulating hormone (FSH) levels on f ollicle growth and oocyte maturity in unstimulated in. vitro fertiliza tion (IVF) cycles. Study Design: We compared cycles with elevated day 3 FSH levels (>20 mIU/ml) to subsequent cycles in the same patients wh en day 3 FSH returned to normal and to cycles among women with normal day 3 FSH levels. Patients: Seven cycles in seven patients had an elev ated day 3 FSH (high-FSH group). These were compared to II subsequent cycles in which there was a return to a normal baseline FSH and to 13 cycles in 13 patients that entered the unstimulated protocol with a no rmal baseline day 3 FSH. Results: The day of human chorionic gonadotro pin (hCG) administration was similar in all groups as were the serum e stradiol (E(2)) levels. Although the high-FSH group tended to have sma ller maximum follicular diameters, the difference was not statisticall y significant. The highest FSH level on cycle day 3 in a completed cyc le was 56.2 mIU/ml. The total number of oocytes aspirated and the numb er of embryos obtained was similar in all groups. Whereas there were n o pregnancies in the high-FSH group, 2 of the subsequent II normal day 3 FSH cycles resulted in clinical pregnancies. Two of the 13 patients in the normal day 3 FSH values also achieved pregnancies. Conclusions : We conclude that cycle day 3 serum FSH levels as high as 56.2 mIU/ml may be associated with apparently normal follicular growth, oocyte fe rtilization, and embryo cleavage in unstimulated cycles. However, preg nancies are not observed. In addition, FSH levels vary widely from cyc le to cycle and elevated levels in one cycle do not necessarily imply that pregnancy may not occur in a subsequent cycle when FSH levels ret urn to normal.