Clinical and endocrine response to pulsatile intravenous gonadotropins in refractory anovulation

We investigated the endocrine response to an experimental protocol in which human menopausal gonadotropin was delivered in pulses every 90-120 minutes by an automated pump. Thirty clomiphene citrate- and gonadotropin-releasing hormone-unresponsive anovulatory women were studied over 107 treatment cycles. In response to episodic intravenous (IV) delivery, pulses of FSH and LH were demonstrable in the circulation. In four World Health Organization (WHO) group I anovulatory women, ovulation occurred in all cycles (N = 8); the pregnancy rate per cycle was 63% and the cumulative pregnancy rate 100%. In 26 WHO group II patients, 42.4% of treatment cycles were in 12 women previously refractory to the intramuscular route of administration; the rate for ovulation was 86% (total of 99 cycles), the pregnancy rate per ovulatory cycle was 14%, and the cumulative pregnancy rate 56%. A mild phlebitis occurred at the site of the IV catheter in 24% of treatment cycles. Intravenous delivery of gonadotropins in small pulses had a dose-sparing effect and was an effective method of treating anovulatory infertile patients refractory to other conventional methods of ovulation induction.