Male hormonal contraception: suppression of spermatogenesis by injectable testosterone undecanoate alone or with levonorgestrel implants in chinese men.

Monthly injections of testosterone undecanoate (TU) act as a male contraceptive by reversibly suppressing spermatogenesis to azoospermia or severe oligoazoospermia in 95% of Chinese men. In 5% of Chinese men, however, monthly TU administered alone fails to suppress spermatogenesis into contraceptive ranges, or sperm "rebound," leading to occurrences of pregnancy during treatment. Since combinations of progestins and androgens are associated with greater degrees of sperm suppression in white men, we hypothesized that the combination of TU and the progestin levonorgestrel (LNG) would result in improved spermatogenic suppression in Chinese men. Sixty-two healthy Chinese men were randomly assigned to one of the following 3 regimens: group I (n = 21) received 4 LNG rods (75 mg each), which were followed 4 weeks later by 500 mg of TU by intra-muscular (IM) injection every 8 weeks for 24 weeks; group II (n = 20) received 4 LNG implants, which were followed 4 weeks later by 1000 mg of TU by IM injection every 8 weeks for 24 weeks; and group III (n = 21) received TU 1000 mg by IM injection every 8 weeks for 24 weeks. Sperm counts, serum testosterone (T), luteinizing hormone, follicle-stimulating hormone, and LNG were measured every 2 weeks before, during, and after treatment. During treatment, group II demonstrated a trend toward a greater attainment of azoospermia than groups I and III (90% vs 62% [group I] vs 67% [group III]; P =.09). Attainments of either azoospermia or oligozoospermia (sperm density, <3 x 10(6)/mL) were 95%, 100%, and 86% for groups I, II, and III, respectively (P >.05 for comparisons between groups). Spermatogenesis in all subjects returned to the normal range after the implants were removed. No serious adverse events and no significant changes in serum chemistry occurred during the study. These results demonstrate that the combination of IM injections of high-dose TU every 2 months and LNG implants is associated with marked suppression of spermatogenesis in Chinese men. The combination of high-dose TU every 2 months and LNG implants is a promising candidate for future large-scale efficacy studies of hormonal male contraception in Chinese men.

Hormonal contraception in Chinese men: variations in suppression of spermatogenesis with injectable testosterone undecanoate and levonorgestrel implants.

AIM: To explore the causes of the difference in spermatogenic suppression between responders and non-responders in Chinese men treated with levonorgestrel (LNG) implants plus testosterone undecanoate (TU) injectable. METHODS: The 16 Chinese volunteers treated were divided into two groups in regard to the sperm count during the treatment period, 7 men in the responder group (Group R), including 6 azoospermia and one severe oligozoospermia, and the remaining 9 in the non-responder group (Group N), including 4 oligozoospermia and 5 with sperm counts greater than 20 x 10(6)/mL. The differences in serum profiles of FSH, LH, T, LNG and T/LH ratio were compared between the two groups and the correlation between the seminal fluid parameters and serum reproductive hormones was analyzed. RESULTS: The serum FSH level was lower in Group R than that in Group N (P<0.05), while the serum LH and LNG levels were higher in Group R than those in Group N (P<0.05). The sperm density (P<0.01, r=0.235), motility(P<0.01, r=0.326) and vitality (P<0.01, r=0.219) showed significantly positive correlation with the serum FSH level. CONCLUSION: The blood LNG and T levels, the degree of FSH inhibition and/or the sensitivity of the pituitary-testis axis to exogenous steroids, as well as the individual spermatogenetic potential and the functional status of the Leydig cells may be factors bringing about individual differences in spermatogenic suppression in Chinese men treated with LNG and TU.

[Effects of mifepristone of different doses on emergency contraception, a randomized double-blind study].

OBJECTIVE: To compare the effects of mifepristone of different doses on emergency contraception. METHODS: 3,052 healthy women with regular menstrual cycle who visited the 10 family planning institutes and hospitals in Beijing, Shanghai, Shangdong, Sichuan, Tianjin, Guangdong, and Liaoning for emergency contraception within the period of 120 hours after a single act of unprotected sex were given a single dose of 10 mg or 25 mg mifepristone randomly and double-blindly. They were asked to record the vaginal hemorrhage that would occur and not to have unprotected sex until the next menstrual onset when they were followed up. The trial for a specific subject ended when she menstruated. If the menstruation was irregular or a specific subject failed to menstruate on time a blood or urine human chorionic gonadotropin (hCG) test was made. If the hCG test was negative, an appointment was made to follow up once one week later. If the hCG test was positive ultrasound examination was made to detect pregnancy. If the subject still failed to menstruate and the hCG test was still negative follow-up for this subject could be finished. RESULTS: Twenty-two of the 3,052 subjects were lost to follow up. Among the remaining 3,030 women 1,516 were in the 10 mg group and 1 514 in the 25 mg group. Seventeen pregnancies occurred in each group, with a pregnancy rate of 1.1% for both groups. The relative risk of pregnancy of treatment of 25 mg mifepristone in comparison with treatment of 10 mg mifepristone was 1.0 (95% CI: 0.51-1.95). Both doses prevented about 85% approximately 86% of the anticipated pregnancy if no measure had been adopted. The pregnancy rate nearly doubled in the women who had unprotected sex after treatment of mifepristone. The efficacy of mifepristone decreased along with the delay of mifepristone administration. Side effects were uncommon and mild. Delay of 7 days or more in the onset of next menstruation occurred in 9%-10% of the women. CONCLUSION: Mifepristone of the dose of 10 mg is safe and effective for emergency contraception. Earlier administration is preferable, although the method can be used effectively up to five days after the unprotected sex.