ABSTRACT
Ovulation induction is a frequently utilized therapeutic procedure for the management of inf ertility. The goals of ovulation induction depend on the medical condition of each couple, and can be grouped in two major categories. Firstly, procedures conducted to restore ovulation in patients with menstrual and ovulatory disorders. The preferred approach in this condition is to use clomiphene citrate, and, when this drug fails, pulsatile gonadotropin-releasing hormone (GnRH) or low-dose gonadotropins. These latter are indicated because of the efficacy and reduced risk of ovarian hyperstimulation and/or multiple conception associated with their use.1,2 Secondly, stimulation of multiple folliculogenesis in normal women undergoing assisted reproductive procedures (ART). Numerous follicles/oocytes are necessary for in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) and thus, full dose gonadotropin regimens are indicated in these subjects. The introduction of gonadotropin-releasing hormone analogues (GnRH-a) into assisted reproduction technique (ART) protocols some 12 years ago greatly contributed to the success of modern IVF treatment. These medications induce pituitary desensitization, thereby suppressing premature endogenous LH surges, reducing cancellation rates, improving the overall number of oocytes retrieved, and improving implantation rates.3,4
Patients with oligomenorrhoea and/or polycystic ovarian disease often respond inappropriately to exogenous gonadotrophins or pulsatile GnRH. On the other hand, patients with profound depression of gonadotropin secretion (e.g. primary hypogonadotropic amenorrhea) are the best candidates for induction of ovulation and show a lower incidence of complications (ovarian hyperstimulation).
