A SEQUENTIAL-ANALYSIS OF THE EFFECT OF PROGESTERONE ON SPECIFIC SPERMFUNCTIONS CRUCIAL TO FERTILIZATION IN-VITRO IN INFERTILE PATIENTS

The objective of these studies was to evaluate the modulatory effect(s ) of progesterone on sperm functions crucial to fertilization in infer tile men with abnormal sperm parameters. A prospective, controlled stu dy applying a sequential diagnostic analysis capable of identifying sp ecific dysfunctions of the male gamete was performed. Patients (n = 14 ) were allocated to the study group if they had a history of infertili ty of >1 year duration and after semen evaluation showed teratozoosper mia (< 14% normal sperm forms as diagnosed by strict criteria) or tera to-asthenozoospermia (<50% progressive motility). After swim-up separa tion of the motile sperm fraction, the following functions were assess ed with and without previous exposure to progesterone (1.0 mu g/ml): a crosome reaction (using Pisum sativum agglutinin), hyperactivated moti lity (using a computerized semen analyser), sperm-zona pellucida bindi ng (in the hemizona assay), sperm-zona pellucida penetration (in a spe rm-zona penetration assay), and sperm-oocyte penetration (using the ha mster zona-free oocyte/sperm penetration assay). Progesterone did not affect the percentage of acrosome-reacted spermatozoa after 1 or 3 h o f incubation. Hyperactivated motility was significantly enhanced by pr ogesterone after Ih (12 +/- 4 versus 6 +/- 2% in controls; P < 0.02). Although progesterone did not affect sperm-zona binding, it significan tly enhanced both sperm-zona pellucida penetration (27 versus 12% in c ontrols; P = 0.03) and sperm-oocyte penetration (15 versus 8% in contr ols; P < 0.05). Because those sperm functions enhanced by progesterone are crucial to fertilization, the steroid may have value in the treat ment of some male-factor patients undergoing assisted reproductive the rapy.