Long-term immunization against the beta-subunit of ovine luteinizing hormone (oLH beta) has no adverse effects on pituitary function in rhesus monkeys.

One postulated safety hazard of contraceptive methods based on immunization against gonadotropic hormones is the possibility that circulating antibodies which crossreact with pituitary hormones may impair pituitary function through the deposition of immunoglobulin and/or complement suggesting immune complexes. In order to evaluate this possibility in rhesus monkeys actively immunized against the beta-subunit of ovine luteinizing hormone (oLH beta), we used three approaches to study the effects of long-term immunization on pituitary function: a) evaluation of pituitary responsiveness to challenge with a GnRH-agonist; b) examination of pituitary histology and immunostaining with gonadotropin antisera; and c) examination of pituitary cells for deposition of immune complexes. Our results indicate that circulating anti-oLH beta antibodies did not result in significant impairment of pituitary function in rhesus monkeys.