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Results for “Contraceptive Effectiveness”

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At least 55 records · Page 3Linked to original sources
PubMed2005

Interaction of St. John's Wort with oral contraceptives: effects on the pharmacokinetics of norethindrone and ethinyl estradiol, ovarian activity and breakthrough bleeding.

OBJECTIVES: This study evaluated the effect of the herbal remedy St. John's Wort on oral contraceptive (OC) therapy with respect to the pharmacokinetics of norethindrone and ethinyl estradiol, ovarian activity and breakthrough bleeding. METHODS: Sixteen healthy women were treated with a low-dose OC (Loestrin 1/20) and a placebo for two consecutive 28-day cycles in a single-blind sequential trial. Treatment with St John's Wort 300 mg three times daily was then added for two additional 28-day cycles. Outcomes compared between control and treatment cycles included the pharmacokinetics of norethindrone and ethinyl estradiol, daily bleeding diaries, follicle growth, changes in cervical mucus and progesterone levels drawn at 7- to 10-day intervals. RESULTS: Treatment with St. John's Wort was associated with a significant 13-15% reduction in the dose exposure from the contraceptive. Breakthrough bleeding increased in the treatment cycles, as did evidence of follicle growth and probable ovulation. CONCLUSION: St. John's Wort is associated with increased metabolism of norethindrone and ethinyl estradiol, breakthrough bleeding, follicle growth and ovulation. Women using OCs should be cautioned that St. John's Wort might interfere with contraceptive effectiveness.

Adult↗
PubMed2006

Contraceptive effect of sperm-agglutinating factor isolated from Staphylococcus aureus in mouse.

OBJECTIVE: To investigate the contraceptive effect of sperm-agglutinating factor (SAF) isolated from Staphylococcus aureus in mouse. DESIGN: Experimental study performed with LACA mice obtained from the Central Animal House, Panjab University, Chandigarh, India. SETTING: In vivo studies conducted in the Department of Microbiology, Panjab University, Chandigarh, India. POPULATION: Sixty female and 18 male mice were used for the studies. METHODS: Mice sperm-S. aureus agglutination, scanning electron microscopy (SEM), in vivo studies in mice. MAIN OUTCOME MEASURE: Contraceptive efficacy of SAF. RESULTS: S. aureus readily adhered to and agglutinated mouse spermatozoa. By SEM, S. aureus adherence was observed on sperm head as well as sperm tail. SAF was found to be causing 100% fertility inhibition in mouse with no effect on vaginal epithelium. CONCLUSIONS: Sperm-agglutinating factor has been found to have a potential as a contraceptive agent.

Agglutinins↗
PubMed2003

Contraceptive effectiveness of a polyurethane condom and a latex condom: a randomized controlled trial.

OBJECTIVE: To compare the contraceptive effectivenesses of a polyurethane condom and a standard latex condom. Secondary outcomes of interest were safety, functionality, discontinuation, and acceptability. METHODS: We randomized 901 couples to use either the polyurethane condom or a standard latex condom as their only form of contraception. We tested for pregnancy at enrollment and at every scheduled follow-up visit (weeks 4, 10, 16, 22, and 30). RESULTS: The 6-month typical-use pregnancy probabilities were 9.0% (95% confidence interval [CI] 5.9, 12.2) for the polyurethane group and 5.4% (95% CI 2.9, 7.8) for the latex group; the hazard ratio was 1.7 (95% CI 1.1, 2.7), and we failed to reject the null hypothesis of our test of noninferiority. Females in the polyurethane group reported fewer genital irritations (hazard ratio 0.6; 95% CI 0.5, 0.8; P <.01), whereas males in both groups reported the same number of genital irritations (hazard ratio 1.0; 95% CI 0.7, 1.5; P =.94). Total clinical failures (breakage and slippage) were 8.4% for the polyurethane condom and 3.2% for the latex condom (difference 5.3%, 90% CI 2.8, 7.7). The risk of discontinuation did not differ between groups. Participants judged both condoms favorably in terms of the four primary acceptability outcomes (willingness to purchase, willingness to recommend, confidence in method, and general comfort). CONCLUSION: The polyurethane condom was not shown to be as effective as the latex comparator condom for pregnancy prevention. However, the risk of pregnancy in the polyurethane group falls in the range of other barrier methods. For people with latex sensitivity or who find latex condoms unacceptable, this polyurethane condom represents one of several synthetic male condom alternatives currently available on the US market.

Adolescent↗
PubMed1999

Timing of onset of contraceptive effectiveness in Norplant implant users. II. Effect on the ovarian function in the first cycle of use.

The objective of this study was to time the onset of contraceptive effectiveness in Norplant implant users, when the capsules were inserted beyond the first 7 days of the cycle, based on the immediate effect on the ovarian activity. A total of 42 healthy women requesting Norplant implant contraception were enrolled at clinics in Santo Domingo, Dominican Republic, and in Baltimore, Maryland. Implants were inserted on days 8-13 of the menstrual cycle. Blood samples for estradiol (E2), progesterone (P), luteinizing hormone (LH) (in a subset of 12 women), and levonogestrel (LNG) assay, were taken at 0 h and at 6, 12, 24, 72, and 168 h postinsertion. Ovulation, as defined by P > 2.5 ng/mL, occurred in 40% of subjects. A short lasting, frequently blunted, LH peak occurred within 12 h postinsertion, in all these subjects. The remaining subjects had anovulatory cycles with two distinct E2 profiles: continuously increasing E2 levels to a high mean of 414.3 pg/mL (28%), or no sustained increase in E2 (32%). Most cycles (86%) in which Norplant was inserted with high E2 levels (> 175 pg/mL) were ovulatory, whereas none were ovulatory with low E2 (< 100 pg/mL) at insertion. Based on the endocrine effects of Norplant implant insertion in the midadvanced follicular phase, in which ovulation will either occur within 48 h of insertion or will be impaired, additional contraceptive protection is necessary only for 3 days.

Adolescent↗
PubMed1991

Contraceptive effects of extended lactational amenorrhoea: beyond the Bellagio Consensus.

We have recorded the duration of lactational anovulation and amenorrhoea in a well-nourished group of Australian women who breastfed their babies throughout the study. The data enabled us to compare the theoretical cumulative probability of conception among breastfeeding women who had unprotected intercourse irrespective of their menstrual status with that of those who had unprotected intercourse only during lactational amenorrhoea. Breastfeeding alone is not an effective form of contraception, since all the women in our study resumed normal ovulation while still breastfeeding. However, among women who have unprotected intercourse only during lactational amenorrhoea but adopt other contraceptive measures when they resume menstruation, only 1.7% would have become pregnant during the first 6 months of amenorrhoea, only 7% after 12 months, and only 13% after 24 months. Thus for our women it would be possible to extend the Bellagio Consensus Conference guidelines which stated that lactational amenorrhoea can only be relied on as a contraceptive for the first 6 months post-partum in women who are fully or almost fully breastfeeding. The lactational amenorrhoea method can be relied on for excellent contraceptive protection in the first 6 months of breastfeeding, irrespective of when supplements are introduced into the baby's diet; for women who continue to breastfeed the method can also give good protection for up to 12 months post partum. Once menstruation has returned, other forms of contraception are essential to prevent pregnancy.

Amenorrhea↗
PubMed2006

Day-specific pregnancy probability estimation in barrier contraceptive effectiveness trials.

We apply an extension of a statistical model developed in the fertility research setting to the barrier contraceptive trial setting to obtain estimates of the probability of pregnancy per cycle day in the presence or absence of barrier use among participants of a randomised trial of female barrier contraceptives. The per cycle day pregnancy curve for the barrier trial participants was similar to previously published results from a fertility study that included a precise indicator of ovulation day. In addition, our analysis showed strong contraceptive effects for the diaphragm. The proposed modelling approach should allow evaluation of the effects of other coitus-specific exposures on the chance of pregnancy in other prospective studies, including fertility studies.

Clinical Trials as Topic↗
PubMed2001

Retrospective vs. prospective coital frequency and menstrual cycle length in a contraceptive effectiveness trial.

PURPOSE: To determine how well information at enrollment would predict coital frequency and menstrual segment length during a prospective contraceptive effectiveness trial. METHODS: We compared retrospective reports of monthly coital frequency and menstrual segment (cycle) length with prospective information for women participating in a contraceptive trial of the Reality((R)) female condom. RESULTS: Participants reported slightly higher mean monthly coital frequency and slightly longer menstrual segments prior to the study than during the study (12.6 acts vs. 12.0 acts per month and 30.8 days vs. 28.4 days). We examined the actual distribution of differences between the retrospective and prospective measures and found considerable variability. Among the 195 participants studied, parous women were less likely to predict accurately menstrual segment length (OR 0.4; 95% CI 0.3--0.9), while older women were more likely to predict accurately coital frequency (OR 1.9; 95% CI 0.9--3.3). CONCLUSIONS: Coital frequency and menstrual segment length vary considerably over time. Hence, prospective data collection is essential to accurately characterize these variations and to properly interpret results from contraceptive trials and other studies concerned with fecundability and hazards of reproduction.

Adult↗
PubMed1994

Long-term contraceptive effects of intrauterine neem treatment (IUNT) in bonnet monkeys: an alternate to intrauterine contraceptive devices (IUCD).

Antifertility effects of intrauterine neem treatment (IUNT) was studied in bonnet monkeys. A single administration of 1 ml of neem oil by an intrauterine insemination catheter blocked fertility for 7 to 12 months. The effect was, however, reversible as all the animals became pregnant subsequently and delivered normal babies. The neem oil treatment had no adverse effect on menstrual cyclicity and ovarian functions. The uterus of neem-treated animals showed normal morphology. Immunohistological studies, however, demonstrated a significant increase in the number of MHC-II antigen-positive cells in the uterine endometrium following neem treatment, indicating enhanced antigen-presenting ability of the uterus; a feature that may be related to the observed antifertility effect of neem oil. The present investigation demonstrates that an IUNT can be used for long-term, reversible contraception, without any apparent side effects, and that the method could provide an alternate to currently used intrauterine contraceptive devices (IUCD).

Animals↗
PubMed2000

Contraceptive effects of levonorgestrel implants in a marsupial.

The effect of subcutaneous levonorgestrel implants on reproduction in female tammar wallabies was investigated during the breeding and non-breeding season. Female tammars were given either a control or a levonorgestrel implant and their pouch young were removed to terminate embryonic diapause. Both the control and the levonorgestrel-implant animals treated during the months of May and June gave birth, demonstrating that levonorgestrel does not prevent the reactivation of the diapausing blastocyst or its subsequent development when given at these times. However, none of the levonorgestrel-treated animals mated post partum, whereas all of the control females that gave birth had a post partum oestrus and mated. Control animals gave birth again when the neonate was removed, and continued to breed normally during the following 36 months of the investigation. None of the levonorgestrel-treated animals gave birth again or mated during the next 36 months. Animals given control implants during December did not reactivate or give birth until the normal start of the breeding season in late January. Animals treated with levonorgestrel implants during December did not reactivate with the control animals at the beginning of the breeding season and did not give birth during the next 36 months. There were no effects of levonorgestrel treatment on early lactation. Levonorgestrel implants were removed from six females and four of these animals resumed reproductive activity, confirming that the contraceptive effect of the implants is reversible. Levonorgestrel implants therefore provide a highly effective, reversible and long-term method of contraception for tammar wallabies. This contraceptive system appears to offer a method of population control for the management of overabundant captive and selected wild populations of macropodid marsupials.

Animals↗
PubMed1994

The non-contraceptive effects of the levonorgestrel-releasing intrauterine device.

Clinical trials have consistently shown that the IUD that releases 20 micrograms levonorgestrel daily (LNG-IUD-20) has a contraceptive efficacy comparable to, if not surpassing, the Copper T380 and the Multiload Copper-375 IUDs. The focus of this review is the device's non-contraceptive effects--the beneficial ones, such as reduction of menorrhagia, a therapeutic effect on dysmenorrhea, and prevention of ectopic pregnancy, as well as the deleterious ones, such as amenorrhea, spotting and irregular bleeding, hormonal side-effects, and functional ovarian cysts. Also discussed are the possibility of a preventive effect on pelvic inflammatory disease, the effects of the IUD on postpartum/lactating women, fertility return after removal and other safety issues. In general, the LNG-IUD-20's non-contraceptive benefits are substantive, carry important medical and public health implications, and far outweigh the device's deleterious effects, which are either medically mild or transient in nature, and can usually be managed satisfactorily by counseling. A better understanding of these effects, both beneficial and deleterious, of this hormone-releasing IUD should lead to more effective patient counseling, which, in turn, should improve user quality of life, minimize unnecessary removals, and maximize continuation of use.

Female↗