Folliculogenesis--the stimulated way.

Abstract

The initial techniques of stimulating follicular development in the anovulatory woman involved the use of human pituitary gonadotrophin (hPG) and thus replaced the function of the pituitary gland. Despite extreme care with administration of hPG and extensive monitoring to assess the ovarian response, ovarian hyperstimulation and multiple pregnancy were common. Less expensive and easier methods of treatment soon followed with oral clomiphene citrate (early 1960s), oral bromocriptine (early 1970s) and pulsatile gonadotrophin-releasing hormone (late 1970s) being used. Currently all of these methods, alone or in combination, are employed and successful ovulation induction (except in women with elevated FSH levels) can now virtually be guaranteed. Controlled ovarian hyperstimulation, just the outcome one was attempting to avoid in the treatment of anovulatory women, has become the treatment of choice for women having in vitro fertilization (IVF) or gamete intrafallopian transfer (GIFT). The extra oocytes produced by this treatment results in more embryos being available for transfer and/or freezing and improves the overall pregnancy rate. The concurrent use of gonadotrophin-releasing hormone agonists (GnRH-a) has resulted in more mature oocytes being developed, less cancelled cycles for a spontaneous midcycle LH surge, and allowed even more embryos to be produced thereby increasing the pregnancy rate further to the current expected 20% per cycle commenced. As techniques are further modified, adverse effects of elevated LH levels on pregnancy and take home baby rates should be able to be overcome, and oocyte freezing and long-term storage should become a possibility.(ABSTRACT TRUNCATED AT 250 WORDS)