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 current literature on the transmission of HIV and the use of oral contraceptives (OCs), injectables, IUDs, spermicides, and the female condom was reviewed. Some of the methodological difficulties involved study design (observational studies, cross-sectional, case control, and prospective studies) and confounding factors (age, marital status, sexual partners). The impact of OC use on HIV transmission is likely to be minor, but some factors contributing to transmission include cervical ectropion, which enhances HIV transmission. Nevertheless, in a 1990 Nairobi study of 4404 women no such association was detected. Sexually transmitted diseases (STDs) have been risk factors in HIV transmission. OCs that decrease irregular bleeding may protect against HIV. Progestin-only pills could act on the risk of HIV transmission by thickening cervical mucus and thinning the vaginal epithelial layer. 21 epidemiological studies were identified on the use of OCs and transmission. Except for a 1990 Nairobi study among prostitutes none of them reported a significant association between OC use and HIV seropositivity. Injectables (Depo Provera) could theoretically increase HIV transmission, but no such conclusive evidence has surfaced. Increased risk of transmission or seropositivity has been reported with IUD use, but this needs confirmation by prospective studies. Among spermicides the nonoxynol-9 sponge slightly increased HIV seroconversion in 139 sex workers in Nairobi in a 1992 study. However, this trial was contradicted by other prospective studies conducted in Cameroon and Zambia. Nonoxynol-9 kills HIV but also damages the cervical and vaginal mucosa enhancing HIV transmission. In 1992 in vitro activity in 26 out of 131 other spermicides screened inhibited HIV. The female condom was tested in 104 women in a 1993 prospective study in the US and no recurrences of trichomonas occurred in 20 women who used it consistently over a 6-week period. More prospective epidemiological studies are needed, and the risk of HIV infection should be part of counseling on contraceptives.
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PMID:Contraceptive methods and the transmission of HIV: implications for family planning. 820 68

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

The relationship between cervical epithelium disorders and cervical ectopy and Depo-Provera use was investigated among African women. The women, aged 35-65 years, had gynecologic examinations, which included various cervical cancer screening tests including two 35-mm colored photographs of the cervix. Cervical photographs from 723 participants were reexamined for the signs of disruption. Results showed that among 121 current Depo-Provera users, 38% showed no steady increase in epithelial disruption compared with 34% of past users and 49% of nonusers. There was no difference in the odds ratio (OR = 1.37; 95% CI: 0.89-2.11). The percentage of women with significant ectopy was higher in current and past users of Depo-Provera, but no trends remain after age adjustment and parity (OR = 1.22; 95% CI: 0.80-1.86). The credibility of the diagnosis of cervical disruption combined (either ulceration, inflammation, or athropy) was excellent (K = 0.8). However, the results were doubtful in light of the concept that simple epithelial thinning may account for putative effects of Depo-Provera. The validity of this method needs further investigations.
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PMID:Prevalence of visible disruption of cervical epithelium and cervical ectopy in African women using Depo-Provera. 1051 30

This study assesses vaginal epithelial thickness and number of cell layers from biopsies taken in the untreated follicular and luteal phases and at 1 month and 3 months after administration of Depo-Provera. Subjects were seen at the CONRAD Clinical Research Center at the Eastern Virginia Medical School, Norfolk, Virginia. Findings showed that there was no significant change over time in either parameter from biopsies obtained in the luteal phase compared with those at either time after Depo-Provera administration. There was also no change in the mean number of Langerhans cells in vaginal wall specimens and no change in cervical ectopy. The dramatic vaginal thinning seen in rhesus monkeys was not observed among these subjects.
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PMID:The effect of one injection of Depo-Provera on the human vaginal epithelium and cervical ectopy. 1054 48

The objective of the study was to evaluate the effect of long-term use of the injectable contraceptive depot medroxyprogesterone acetate (DMPA) on human vaginal histology. Twenty premenopausal women currently using DMPA as a contraceptive method for two and three years were compared with 20 regularly menstruating women, who never used Depo-Provera and/or other kind of hormonal contraceptive in the last 6 months prior to the study. Subjects and controls were matched by age (+/-1 year), body mass index (kg/m2) (+/-1.0), number of pregnancies (+/-1), age at first intercourse (+/-1 year), years of sexual activity (+/-1 year), and number of partners during their life (+/-1). Vaginal biopsies were performed in users at 90+/-7 days after the last injection and in nonusers at day 20-25 of the menstrual cycle. In addition, at the day of the biopsy a blood sample was collected to measure estradiol (in all women) and DMPA in users. The level of serum estradiol was significant lower in Depo-Provera users than in controls (p < 0.001). The thickness of the vaginal epithelium was not smaller among DMPA users than among controls, the mean count of Langerhans cells per mm of epithelium were almost identical in both groups, and no significant differences were found on the vaginal maturation indices. In conclusion, the use of Depo-Provera between two and three years did not affect vaginal thinning of the epithelium, Langerhans cell count or maturation index.
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PMID:The effect upon the human vaginal histology of the long-term use of the injectable contraceptive Depo-Provera. 1102 25

Several small studies conducted by the Centers for Disease Control and Prevention (CDC) have shown that although progesterone appears to increase the likelihood of simian immunodeficiency virus (SIV) transmission in exposed monkeys, women using hormone contraceptives do not appear to have the same increased risk for HIV. The results, published in the May issue of Science, show little, if any, increase in the rate of HIV infection in women on Depo-Provera, an injectable contraception containing progestin, compared to those who were not taking it. Another study, conducted in Thailand, found similar results. However, this contrasts sharply with the results of a monkey study that found that rhesus monkeys given progesterone experienced significant thinning of the vaginal wall. Researchers are examining the effects of progesterone on the lining of the vagina. Researchers are finding some thinning, but not to a significant degree. The CDC continues to stress that only abstinence or the use of latex condoms can prevent the spread of AIDS.
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PMID:Progesterone-HIV link questioned by new studies. 1136 49

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

Depo-Provera (medroxyprogesterone acetate), a long-acting derivative of progesterone, is utilized during many nonhuman primate microbicide studies to facilitate simian immunodeficiency virus (SIV) infection by thinning the vaginal epithelium. To date, the systemic effects of this steroid hormone in regard to SIV/HIV pathogenesis are not well understood, but an increase in infection rates and lymphoproliferation following progesterone application has been reported. Therefore, a proactive study using 20 Chinese rhesus macaques was designed to investigate the effect of a single Depo-Provera injection on SIV disease progression. Group 1 (n = 10) was treated with 30 mg Depo-Provera intramuscularly 30 days prior to intravenous challenge with 50 TCID(50) SIVmac251, while Group 2 (n = 10) remained untreated, but received the same amount of SIV. Blood samples were taken at predetermined intervals to measure RNA viral loads, CD4(+), CD8(+), and CD20(+) lymphocyte counts and percentages and absolute numbers of naive and memory T lymphocytes. Upon statistical endpoint data analysis, none of the parameters measured were shown to be significantly different between the groups. One animal in the Depo-Provera-treated group and two macaques in the control group were euthanized prior to study end due to the development of clinical signs (in weeks 43 and 51, respectively). All other animals were euthanized between weeks 68 and 71 post-SIV infection. Histopathological evaluations revealed that 5 of 10 animals in each group had developed simian AIDS (SAIDS). In summary, this prospective study demonstrated that a single injection of 30 mg Depo-Provera did not have a significant influence on SIV disease progression.
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PMID:Depo-Provera does not alter disease progression in SIVmac-infected female Chinese rhesus macaques. 2037 24