A multicentre efficacy and safety study of the single contraceptive implant Implanon. Implanon Study Group.
(2/94)
An open, multicentre study was performed to assess efficacy, safety and acceptability of the single-rod contraceptive implant Implanon. The study involved 635 young healthy women, who were sexually active and of childbearing potential. The women were followed up every 3 months over the entire study period. Originally the study was designed for 2 years, but was extended to 3 years in a group of 147 women from two centres. Altogether, 21 centres in nine different countries participated. The average age of the women was 29 years (range 18-42 years), of whom 83.5% had been pregnant in the past. No pregnancy occurred during treatment with Implanon, resulting in a Pearl Index of 0 (95% confidence interval: 0.0-0.2). In the first 2 years, 31% had discontinued the treatment. Of the 147 women in the study extension, nine discontinued (6%) treatment. Bleeding irregularities was the main reason for discontinuation during the first 2 years of use (17.2%) and adverse experiences in the third year (3.4%). Implant insertion and removal were fast and uncomplicated in the vast majority (97%) of cases. Return of fertility was prompt. In conclusion, Implanon has excellent contraceptive action during its lifetime of 3 years. The safety profile is acceptable and not essentially different from progestogens in general. (+info)
A comparison of the inhibition of ovulation achieved by desogestrel 75 micrograms and levonorgestrel 30 micrograms daily.
(3/94)
A randomized, double blind, group comparative study was performed over a 12 month period to compare inhibition of ovulation during the use of two (progestogen-only) oral contraceptives containing doses of 75 micrograms desogestrel or 30 micrograms levonorgestrel. Seventy-one female volunteers with regular cycles and established ovulation by ultrasonography and serum progesterone concentrations were recruited from an out-patient clinic in a university hospital and asked to participate in the study. Transvaginal ultrasonography and serum oestradiol, progesterone, luteinizing hormone (LH) and follicle stimulating hormone (FSH) measurements were performed throughout the 7th and 12th 28 day treatment period. Desogestrel at a dose of 75 micrograms showed a significant inhibition of ovulation compared to 30 micrograms levonorgestrel (P < 0.001). (+info)
Venous thromboembolic disease and combined oral contraceptives: A re-analysis of the MediPlus database.
(4/94)
In October 1995 the Committee on Safety of Medicines advised UK doctors and pharmacists that oral contraceptives containing desogestrel and gestodene were associated with double the risk of venous thromboembolic events (VTE) compared to pills containing other progestogens. In 1997 data was analysed from the MediPlus database of UK general practitioner records, which reported odds ratios for desogestrel and gestodene lower than that for levonorgestrel. Here the results of a more stringent nested case control analysis on the MediPlus database are reported. The study was larger and cases were verified. A crude incidence of idiopathic VTE was found amongst users of combined oral contraceptives of 4.6 per 10 000 exposed women years. Using levonorgestrel 150 microg + ethinyloestradiol 30 microg as reference, non-significant odds ratios of 1.1 (0.5-2.6) for desogestrel 150 microg + ethinyloestradiol 30 microg and 1.1 (0.5-2.4) for gestodene 75 microg + ethinyloestradiol 30 microg were found. The results of this study show no significant difference in risk between different formulations of combined oral contraceptive. (+info)
The differential risk of oral contraceptives: the impact of full exposure history.
(5/94)
Previous discussions have indicated that the small increases of risk of venous thromboembolism (VTE) associated with newer combined oral contraceptives (third generation, containing desogestrel and gestodene) may be attributed to bias due to cohort effects. In a case-control analysis, this may produce an overestimate of risk of newer preparations. In 10 centres in Germany and the UK, the Transnational Study analysed data from 502 women aged 16-44 years with VTE, and from 1864 controls matched for 5-year age group and region. Information on lifetime exposure history from all subjects was added to the dataset used in previous analyses and entered into a Cox regression model with time-dependent covariates. Based on 17 622 continuous exposure episodes comprising 47 914 person-years of observation, the adjusted hazard ratio (equivalent to odds ratio, OR) of VTE for the comparison of current users of third-generation versus current users of second-generation (primarily levonorgestrel compounds) combined oral contraceptives was 0.8 (0.5 to 1.3). The OR obtained in standard case-control analysis had been 1.5 (1.1 to 2.1). Adjustment for past exposures includes more information and appears more valid than the standard cross-sectional analysis. Using this approach, the Transnational Study data show no evidence for an increased risk of VTE with third- compared with second-generation combined oral contraceptives. (+info)
The effect of etonogestrel on VEGF, oestrogen and progesterone receptor immunoreactivity and endothelial cell number in human endometrium.
(6/94)
Contraceptive use often leads to disrupted endometrial bleeding patterns in women. In this study, two different contraceptive regimes (Mircette, a monophasic oral contraceptive and Implanon, a long-acting gestagen) were used and their effects on the immunoreactivity of vascular endothelial growth factor (VEGF), oestrogen receptor (ER), progesterone receptor (PR) and endothelial cell number were determined. During the untreated normal cycle, there was a significant increase (P = 0.005) in glandular VEGF immunoreactivity and a significant decrease (P < 0.05) in PR immunoreactivity in the mid- and late secretory phases compared with the proliferative phase. There was a significant positive correlation (gamma = 0.38, P = 0.046) between stromal VEGF immunoreactivity and endothelial cell number. This correlation was also apparent during treatment with Implanon, but not with Mircette. Disrupted bleeding patterns were associated with Implanon and, to a lesser extent, with Mircette. Both contraceptives significantly reduced glandular VEGF immunoreactivity. Implanon significantly increased (P = 0.016) glandular PR staining, but Mircette significantly reduced (P = 0.027) stromal PR staining when compared with secretory before-treatment biopsies. There were no changes in endothelial cell number or glandular or stromal ER during the normal cycle, or with use of either contraceptive. There was no association between the parameters measured with bleeding patterns and histological category. (+info)
Bone mineral density during long-term use of the progestagen contraceptive implant Implanon compared to a non-hormonal method of contraception.
(7/94)
An open, prospective, comparative study was done in healthy women, aged between 18 and 40 years, to study the effects of long-term etonogestrel treatment on bone mineral density (BMD). The control group used a non-hormone-medicated intrauterine device (IUD). The BMD was measured using a dual energy X-ray absorptiometry instrument. Measurements included the lumbar spine (L(2)-L(4)), the proximal femur (femoral neck, Ward's triangle, trochanter) and distal radius. The period of treatment was 2 years and 44 women in the Implanon group and 29 in the IUD group provided data. Groups were comparable at baseline with respect to age, weight, body mass index, BMD and 17beta-oestradiol status. Changes from baseline in BMD in the Implanon group were not essentially different from those in the IUD group. There was no relationship between 17beta-oestradiol concentrations and changes in BMD in this study population. The results of the present study indicate that Implanon((R)) can safely be used in young women who have not yet achieved their peak bone mass. (+info)
Single monthly administration of the anti-progestagen Org 31710 in users of the 75 microg desogestrel progestagen-only pill: effects on pituitary-ovarian activity.
(8/94)
Endocrine and ultrasound effects were studied of an intermittent (every 28 days) oral administration of 150 mg of the anti-progestagen Org 31710 during the continued daily use of 75 microg desogestrel (DSG) for progestagen-only contraception. A randomized, double-blind, placebo-controlled two-centre study was conducted in 50 healthy volunteers. Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), oestradiol and progesterone concentrations, and follicle number and size were studied, as well as endometrial thickness, which was assessed by transvaginal sonography at least twice weekly during a single medication cycle (cycle 3-5). Forty-eight women were evaluated (Org 31710, n = 25; placebo, n = 23). Seven ovulations were observed in the treated group versus none in the placebo group. LH concentrations were higher on days 9 and 11 and oestradiol concentrations lower on day 3 in the treated group, irrespective of whether ovulation occurred. No parameter could predict ovulation. Endometrial thickness was greater on cycle days 7-13 and 19 in the treated group. However, within the Org 31710 group, no significant differences were found in volunteers who did or did not ovulate. Observed differences may be attributed to a competitive effect of Org 31710 with progestagen-induced suppression of the pituitary-ovarian axis, altered oestradiol feedback mechanisms, and/or altered receptor availability. (+info)