Release characteristics, ovarian activity and menstrual bleeding pattern with a single contraceptive implant releasing 3-ketodesogestrel.

The properties of a single contraceptive subdermal implant releasing 3-ketodesogestrel were assessed in fifteen women over twelve months. Serum levels of 3-ketodesogestrel were monitored regularly following insertion and after removal. The mean serum level of 3-ketodesogestrel was 245 pg/ml after 72 h (steady state) and 176 pg/ml after twelve months. All volunteers demonstrated ovulation inhibition throughout the study. Transient oestradiol peaks occurred during the study. No luteal activity was noted. The cervical mucus was rapidly rendered hostile to sperm migration. Two women withdrew from the study during the first six months for medical reasons. Both volunteers cited bleeding irregularity as the main cause, one complaining of oligomenorrhoea, the other of prolonged bleeding/spotting episodes. A small but significant increase in weight was noted during the study period.

PIP: 15 sterilized women participated in a clinical trial of the implant Implanon (Organon), a single ethylene vinyl acetate rod containing 60 mg 3-ketodesogestrel (3-KDG), the metabolite of desogestrel. The rod is 40 mm long, 2 mm in diameter and is packaged in its inserter. In this trial the implants were treated to simulate the 2nd year of use. The study subjects underwent intensive hormone and ultrasound monitoring for 72 hours after insertion, twice weekly for 6 weeks and at 6-month intervals. 13 women completed 6 months, 7 completed 12 months, and 5 continued the trial 24 months. There were no complications related to insertion or removal. 3-KDG levels rose to a steady state of 245 pg/ml by 72 hours, then fell to a mean of 17 pg/ml at 12 months. 90 pg/ml of 3-KDG is the critical serum level for anovulation. After removal, 3-KDG declined to 54 pg/ml in 3 days. Follicle development tended toward small follicles or those larger than 10 mm. There was no luteal activity, and LH, FSH and progesterone remained in the follicular phase range. Estradiol levels were not low enough to risk osteoporosis. There was no significant change in serum sex hormone binding globulin. Systolic blood pressure decreased significantly at 12 months; mean weight gain was 3.7 kg (range from loss of 4 kg to gain of 22 kg); a variety of bleeding irregularities were recorded by individual women.

Comparison of uterine concentrations of ethinyl estradiol and etonogestrel after use of a contraceptive vaginal ring and an oral contraceptive.

OBJECTIVE: To compare uterine tissue concentrations of ethinyl estradiol (EE) and etonogestrel (ENG) after one cycle of use of a contraceptive vaginal ring (NuvaRing; NV Organon, Oss, The Netherlands) or a combined oral contraceptive (COC). DESIGN: Randomized, open-label, pharmacokinetic study. SETTING: Obstetrics and gynecology unit. PATIENT(S): Eight premenopausal women about to undergo hysterectomy but otherwise healthy. INTERVENTION(S): One cycle (17-21 days) of NuvaRing or COC treatment that ended with surgical hysterectomy. MAIN OUTCOME MEASURE(S): Tissue concentrations of EE and ENG in uterine tissue samples taken from the upper myometrium and mid-myometrium, the cervical region, and the endometrium. RESULT(S): In both groups, concentrations of EE and ENG were similar in uterine tissue taken from the upper myometrium and mid-myometrium and the cervical region. However, compared with the COC group, concentrations of both hormones were markedly lower in tissue samples from the endometrium of women who had been treated with NuvaRing. CONCLUSION(S): Vaginal administration of hormones with NuvaRing did not produce elevated uterine concentrations of EE and ENG, compared with an oral contraceptive.