Androgen levels in women using Norplant implants

Comparison of vaginal and oral administration of emergency contraception

OBJECTIVE

To compare the physiologic effects of vaginally and orally administered emergency contraception.

DESIGN

Prospective, open-label, crossover study.

SETTING

University research center.

PATIENT(S)

Nine regularly menstruating volunteers.

INTERVENTION(S)

Five subjects received 1,000 microg of levonorgestrel with 200 microg of ethinyl E2 (twice the standard Yuzpe regimen dose) vaginally, and the standard Yuzpe regimen dose orally 1 week later. Four subjects received 1,500 microg of levonorgestrel (twice the standard Plan B regimen dose) vaginally and received the standard Plan B dose orally 1 week later. Serum samples were obtained at baseline and at frequent intervals after each dose.

MAIN OUTCOME MEASURE(S)

Serum gonadotropin, hepatic globulin, and androgen levels measured at baseline, at the time of peak levonorgestrel, and 24 hours later.

RESULT(S)

Gonadotropin, hepatic globulin, and androgen levels were suppressed to a similar degree among the four regimens, with a return to baseline levels after 24 hours.

CONCLUSION(S)

We conclude that high doses of levonorgestrel found in emergency contraception regimens lead to a transient direct suppression of gonadotropin, hepatic globulin, and androgen levels. This effect is similar after vaginal and oral administration of emergency contraception. Therefore, the vaginal route of administration of emergency contraception regimens may be as efficacious as the oral route.

Post-marketing surveillance of Norplant® contraceptive implants: II. Non-reproductive health

This controlled cohort study aimed to evaluate the safety and efficacy of Norplant contraceptive implants in developing countries. Women initiating Norplant implants were index subjects and women initiating intrauterine devices (IUDs) or surgical sterilization were controls. Consenting participants at 32 clinics in eight developing countries were admitted and followed-up every 6 months for 5 years. Major and less serious health events during follow-up were recorded. Incidence rate ratios of health events adjusted for clinic were estimated for initial and current method use. This paper reports non-reproductive health events. The study involved 7,977 women initiating use of Norplant, 6,625 of IUD, and 1,419 of sterilization. Five years follow-up was completed for 94.6% of the women. The study accumulated 78,323 woman-years of observation. The initial method chosen accounted for 84.4% or more of observed woman-years in users of Norplant, IUD, or sterilization. Twenty-two of the recorded 34 deaths were due to accidents, suicide or homicide. Few deaths or major health events were due to cancer or acute cardiovascular diseases and were not associated with the contraceptive method used. The incidence rates of major health events were low and with two exceptions, there was no significant excess risk of serious morbidity for Norplant users compared with controls; among Norplant initiators gallbladder disease occurred at an incidence rate of 1.5 per 1,000 woman-years and was weakly associated with use of Norplant (rate ratio 1.52 [95% C.I. 1.02, 2.27]). For current Norplant users compared to controls, the rate ratio of a combined variable of hypertension and borderline hypertension was significantly elevated (1.81, [1.12, 2.92]). The occurrence of less serious health events was also low and several of them were significantly more often reported among Norplant users. Headache-migraine, weight gain, mood disturbances, pruritus, eczema, and acne had incidence rates among Norplant users of 11.5, 4.5, 2.8, 1.5, 1.4, and 0.9 per 1,000 woman-years, respectively, and were significantly higher than in controls. Respiratory health problems, nonspecific symptoms, and several ill-defined conditions were also significantly more often reported for Norplant users, but some of the excess incidence may be attributable to reporting and detection bias. The study confirms the safety with respect to serious disease of Norplant, IUDs, and sterilization.

Androgen levels in women using a single implant of nomegestrol acetate

This study was undertaken to evaluate the effects of a single implant containing nomegestrol acetate (Uniplant) on plasma levels of sex hormone-binding globulin (SHBG), testosterone, free testosterone, androstenedione and on blood pressure, body weight, and the development of acne vulgaris. Plasma levels of sex hormone-binding globulin, testosterone, free testosterone and androstenedione were measured. Blood pressure and body weight were determined. The development of acne vulgaris was evaluated. Total testosterone and androstenedione decreased significantly during two years of Uniplant use but all levels were within the normal range. There were no significant differences in sex hormone-binding globulin and free testosterone during 24 months of Uniplant use. All changes observed in this study were within normal range. SHBG was not affected by Uniplant use. No significant increase in androgen levels and in the development of acne vulgaris was observed in these women using nomegestrol acetate implant during two years. Based on these results, it is possible to conclude that Uniplant had no androgenic effect in women during this study.

Effects of an implant of nomegestrol acetate, a 19-nor-progesterone derivative, on thyroid function

This study was undertaken to assess tri-iodothyronine (T3), thyroxine (T4), thyroid stimulating hormone (TSH), T3 uptake, free T3 and free T4 in nomegestrol acetate implant (Uniplant) users. A total of eighteen volunteers of reproductive age who wanted to avoid conception were enrolled in the study. All subjects were investigated before starting treatment. Blood samples for hormonal analysis were taken prior to insertion of the implant. Thereafter, blood samples were drawn at 3, 6, 12, 18 and 24 months of Uniplant use. All subjects had used non-hormonal contraceptives for at least 6 months prior to insertion of the implant. The results observed in this study showed that there was no significant difference in tri-iodothyronine (T3), thyroxine (T4) and thyroid stimulating hormone (TSH) during two years of Uniplant use. No significant difference was found in free T3 levels during two years of Uniplant use. A significant decrease was observed in T3 uptake (p < 0.05) in month 24 and in free T4 (p < 0.05) in month 3 of Uniplant use. All changes observed in this study were inconsistent and all levels were within the normal range.

Plasma levels of cortisol and corticosteroid binding globulin during use of Norplant-2 implants

Plasma levels of cortisol and corticosteroid binding globulin (CBG) were studied during one year in eleven healthy women using NORPLANT-2 implants. NORPLANT-2 implants release approximately 50 ug of levonorgestrel/day. A significant diurnal variation of cortisol levels was found during the study. No significant change in cortisol levels compared to pretreatment levels was found. Levels of CBG showed no diurnal variation, but decreased significantly during use of the implants. This was most probably due to a direct effect of the levonorgestrel, as the levels of estradiol did not change compared to pretreatment levels, except for the values after 6 months that were significantly lower than pretreatment levels. A "free cortisol index" calculated as: level of cortisol/level of CBG, was unchanged during treatment compared to pretreatment levels. It is concluded that although CBG levels were reduced, no significant change in cortisol patterns was seen during use of the implants.

Levonorgestrel concentrations in maternal and infant serum during use of subdermal levonorgestrel contraceptive implants, Norplant, by nursing mothers

The transfer of levonorgestrel to infants was studied in 42 lactating women in whom the contraceptive subdermal implants, Norplant, were inserted 30 to 40 days postpartum. The women breastfed their infants for one year. Simultaneous mother and infant blood samples were taken once during the year. The levonorgestrel serum concentrations were measured by radioimmunoassay. During the first postinsertion month, the levonorgestrel concentration in the infants serum amounted, on the average, to 5% of the maternal concentration. Thereafter, the ratio ranged from 8 to 13%. The implications of this finding are discussed.