Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The objective of this study was to determine whether progestin-only contraceptives induce thinning of the vaginal epithelium in nonhuman primates. Eight intact rhesus monkeys (four per group) were treated with either a single intramuscular injection of 30 mg of Depo-Provera or a subcutaneous insertion of Norplant-II (2 x 75 mg rods; day 0). Norplant-II rods were removed 90 days after insertion. Vaginal biopsies were obtained during a pretreatment menstrual cycle and following treatment on days 10, 30, 60, 118, and 146. Formalin-fixed vaginal biopsies were evaluated for epithelial thickness and the degree of keratinization. The circulating levels of estradiol, progesterone, medroxyprogesterone acetate (MPA), or levonorgestrel (LNG) were monitored throughout the study by specific radioimmunoassays. Circulating levels of estradiol and progesterone confirmed the stage of the menstrual cycle in which pretreatment biopsies were obtained. Following treatment with Depo-Provera, serum levels of MPA increased to 2.3 +/- 0.6 ng/ml (x +/- SE, n = 4) within 24 hr. Serum levels of MPA were maximal on day 14 (5.5 +/- 0.9 ng/ml), dropped below 1 ng/ml by day 50, and were nondetectable by day 70. Circulating levels of LNG were elevated 24 hr after insertion of Norplant-II (5.8 +/- 3.0 ng/ml), peaked on day 2 (7.6 +/- 4.2 ng/ml), remained between 1.4 and 6.2 ng/ml from days 14 to 90, and were nondetectable by day 118, the first serum sample after removal of Norplant-II. There were no significant differences (p > 0.05) in the epithelial thickness (microm), number of epithelial cell layers, or type of epithelium present in vaginal biopsies obtained during the follicular or luteal phases of the pretreatment menstrual cycle. Conversely, a pronounced effect of progestin treatment was observed on the vaginal epithelium. There were no significant differences (p > 0.05) between the two progestin treatment groups, but a significant effect (p < 0.05) over time was observed (two-way ANOVA). Compared with pretreatment menstrual cycle controls, the vaginal epithelial thickness was decreased (p < 0.05) by day 30 or 60 following Norplant-II insertion or Depo-Provera injection, respectively. The number of epithelial cell layers was also decreased (p < 0.05) on days 30 and/or 60 in progestin-treated monkeys compared with pretreatment control cycles. Following removal of Norplant-II or metabolic excretion of MPA, the vaginal epithellium regenerated and the thickness was no longer different (p > 0.05) from the pretreatment control cycle. These data demonstrate that progestin-only contraceptives induced thinning of the vaginal epithelium in rhesus monkeys, and this effect was rapidly reversible following physical or metabolic removal of the progestin.
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PMID:Effects of two progestin-only contraceptives, Depo-Provera and Norplant-II, on the vaginal epithelium of rhesus monkeys. 958 96

After a recent study showing that monkeys given progesterone are more likely to acquire simian immunodeficiency virus (SIV), women's reproductive health experts are advising clinicians to stress the importance of condom use and calm worried women by pointing out that other studies are needed to understand the relationship between hormones and HIV risk. Researchers have learned that progestin causes a thinning of the vaginal wall--possibly an explanation for the increase in SIV infection in the monkey study. Because Depo-Provera and Norplant are long-acting progestin-based contraceptives, women using them to prevent pregnancy may be especially alarmed by reports of the monkey study. Women should be advised that using these contraceptives do protect them from pregnancy; women should assess the risk of contracting HIV or other sexually transmitted diseases; and women should modify their behavior to lower their risk.
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PMID:Advice for women seeking progesterone counseling. 1136 50

In response to the need of some women for long-acting, effective and safe contraceptives, the scientific community developed non-biodegradable progestational subdermal implants that act by making the cervical mucus viscous, with ovulation inhibition and thinning of the endometrial lining. The contraceptive protection is within 24 hours and the cumulative failure rate is low. Contraceptive implants require little or no motivation following adequate counselling. In current use are multirod implants (Norplant I and Norplant II Jadelle) and single rod implant (Implanon and Uniplant). Although menstrual symptoms associated with progestational regimens are the major compliance and acceptability factors within the first year of use, menstrual disturbance generally improves. Continuation rates for implant use are high among those who have had adequate pre-insertion counselling because the perceived advantages greatly outweigh the nuisance effects. Other side effects of implants are similar to those observed with hormonal pills--headache, weight changes, mood swings and abdominal bloating. Training of physicians and nurses in the art of insertion and removal techniques is a pre-requisite for a successful implant programme. This should also be backed by integration of implants into the national commodity logistics systems to ensure adequate local budgetary provision for contraceptive implant procurement rather than reliance on donor supply.
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PMID:Contraceptive implants. 1610 51