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Results for “Contraceptive Effectiveness”

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At least 19 recordsLinked to original sources
PubMed2005

Cost-effectiveness and contraceptive effectiveness of the transdermal contraceptive patch.

OBJECTIVE: The purpose of this study was to examine implications of increased perfect use on the cost-effectiveness of the contraceptive patch compared with combination oral contraceptives (COCs). STUDY DESIGN: This study compared the patch with low-estrogen-dose COCs. It assumes that the risks of developing a medical condition during use are the same for both the patch and COCs. Differences in net cost and pregnancies avoided during use were modeled. With the use of a pharmacoeconomic model, both methods were compared with a hypothetical reference case of contraception nonuse. The base-case model considered women, ages 15 to 50, in average health in a long-term, mutually monogamous, heterosexual relationship. RESULTS: The base-case analysis showed that use of the patch resulted in a savings of 249 US dollars and 0.03 pregnancies per woman over 2 years compared with COCs. CONCLUSION: This analysis demonstrated that patch use would be cost saving compared with COC use, resulting in a net avoidance of pregnancy for this population. The cost savings are attributed to reduced costs of pregnancy.

Administration, Cutaneous↗
PubMed1997

Contraceptive effect of sperm-agglutinating monoclonal antibodies in rabbits.

Immune infertility in humans correlates clinically with the presence of anti-sperm antibodies that trap (agglutinate) sperm in semen and cervical mucus. To test whether sperm-agglutinating antibodies can be effective contraceptive agents, several mouse anti-rabbit sperm (MARS) sperm-agglutinating monoclonal antibodies (mAbs) were developed that rapidly and completely agglutinate sperm: MARS-M3 (IgM), MARS-G16 (IgG3), and MARS-G17 (IgG3). Contraceptive efficacy of these mAbs was tested by mixing the mAb with 0.1 ml semen (approximately 1/5 of a whole ejaculate) immediately before artificially inseminating rabbits paracervically. This paracervical dose of semen provided a rigorous test since it delivered several thousand times more fertilizing doses than does a human ejaculate. All of the mAbs were contraceptively effective, and MARS-G16 reduced the number of fetuses per animal by 88% and 95% with doses of 150 microg and 2 mg, respectively. The contraceptive efficacy of the MARS mAbs in the rabbit suggests that human sperm-agglutinating mAbs may be effective agents for vaginal contraception in humans.

Animals↗
PubMed1980

The effect of ampicillin on oral contraceptive effectiveness.

The effectiveness of oral contraceptives with concomitant use of ampicillin has been questioned. Eleven volunteer subjects were studied during 2 consecutive menstrual cycles; they were given Demulen with placebo or ampicillin during each of the cycles. Serum estradiol (E2), progesterone (P4), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were evaluated on days 13 and 19 of each cycle. Testosterone-binding globulin (TeBG) capacity and ferning of cervical mucus were evaluated on day 13 of each cycle. Subjective symptoms were recorded. All cycles appeared to be anovulatory. Steroid suppression was present in 10 of 11 patients during both cycles. Estrogen-dependent TeBG was not affected by ampicillin. It is possible that cervical mucus ferning was improved by concurrent ampicillin administration. Ampicillin appears unlikely to diminish the effectiveness of the oral contraceptive studied.

Adult↗
PubMed2006

Factors associated with effective contraceptive use among a sample of Latina women.

Unintended pregnancy disproportionately affects Latina women. One factor contributing to unintended pregnancy among Latinas is the low rate of contraceptive use. This study examined correlates of effective contraceptive use among a sample of Latina women (n=202) at increased risk for HIV. In addition to traditional intrapersonal variables (i.e., perceived risk of pregnancy, motivation to avoid pregnancy), the present study examined the role of the male partner and relationship factors (i.e., relationship commitment, duration, pregnancy prevention decision-making) on contraceptive use. Participants were recruited from clinics and community locations in East Los Angeles and administered a 60-minute in-person interview. Multivariate logistic regression was used to compare women who consistently used effective contraceptives (36%) to women using no method or an ineffective method. Women in relationships of 1 to 2 years were nearly 3 times more likely to use an effective contraceptive compared to women in relationships of less than 1 year (odds ratio (OR)=2.7, 95% CI 1.1, 6.7). Women were more than twice as likely to use an effective method if they reported a high level of involvement in decision-making about whether to use contraception (OR=2.3, 95% CI 1.1, 4.7) or had discussed contraception with their partner (OR=2.4, 95% CI 1.03, 5.6). This study provides additional information about the importance of male partners and relationship factors in contraceptive use among Latina women. Efforts to prevent unintended pregnancy need to address the role of relationship factors in the sexual risk and protective behaviors of Latinas.

Adult↗
PubMed1997

Reversible contraceptive effect of PH-20 immunization in male guinea pigs.

Sperm proteins are currently being studied as antigens on which to base a contraceptive vaccine. Sperm plasma membrane proteins offer the theoretical possibility of immunizing either males or females and achieving a contraceptive effect. In this study, we investigated the sperm plasma membrane protein PH-20 as an antigen for inducing infertility in males. We found that infertility can reproducibly be induced in male guinea pigs immunized with purified PH-20: 100% (29 of 29) of PH-20-immunized males became infertile, whereas all 22 controls were fertile. The males were extremely responsive to PH-20 immunization: infertility could be induced with a single injection of only 5 microg PH-20. Among males that received their initial injection when they were approximately 300 g (body weight), 14 of 15 had regained fertility at about 1 yr after initial injection. Surprisingly, in another group of males that received their first injection when they were approximately 650 g (body weight), only 1 of 5 had regained fertility about 1 yr after initial injection. Anti-PH-20 titers in antisera (2 mo after initial injection) were generally in the range 1.1-4.2 x 10(4) in twice-injected males and the range 1.8-9.4 x 10(3) in once-injected males. Over the next 6-11 mo, twice-injected males' titers decreased > or = 4-fold, whereas once-injected males' titers decreased slightly (1.1 - to 1.8-fold). After 6-11 mo, anti-PH-20 titers were in the range 1.0-4.8 x 10(3), and the precise residual titer did not correlate with fertility/infertility. The results show that immunization of males with PH-20, even at low doses, results in a reproducible, completely effective contraceptive action.

Animals↗
PubMed2000

Women's knowledge of, and attitudes to, contraceptive effectiveness and adverse health effects.

Our objectives were to determine women's knowledge of the effectiveness of different contraceptive methods and the risks of thrombosis with use of hormonal contraceptives, and their attitudes regarding the acceptability of bleeding irregularities and weight change. An additional aim was to determine what information women want to be given about contraceptives. In order to satisfy the study objectives, a series of semi-structured focus groups was conducted with women of differing life-stage and background from Oxford. Quantitative data were collected using a structured questionnaire. Qualitative data were collected through discussion with group members. Forty-five women attended four focus groups. Women were segregated into the following groups: professional working mothers; non-professional mothers; young, unmarried professional women; and undergraduate students. Women tended to overestimate the risks and underestimate the effectiveness of hormonal contraceptives. They were resistant to interference with their bleeding patterns and weight.

Adolescent↗
PubMed2006

Steroidal contraceptives: effect on bone fractures in women.

BACKGROUND: Steroidal contraceptive use has been associated with changes in bone mineral density in women. Whether such changes increase the risk of fractures later in life is not clear. However, osteoporosis is a major public health concern. Age-related decline in bone mass increases the risk of fracture, especially of the spine, hip, and wrist. Concern about bone health influences the recommendation and use of these effective contraceptives globally. OBJECTIVES: To evaluate the effect of using hormonal contraceptives before menopause on the risk of fracture in women SEARCH STRATEGY: We searched MEDLINE, POPLINE, CENTRAL, EMBASE, and LILACS for studies of fracture or bone health and hormonal contraceptives. We wrote to investigators to find additional trials. SELECTION CRITERIA: Randomized controlled trials were considered if they examined fractures, bone mineral density (BMD), or bone turnover in women with hormonal contraceptive use prior to menopause. Studies were excluded if hormones were provided for treatment of a specific condition rather than for contraception. Interventions could include comparisons of a hormonal contraceptive with a placebo or with another hormonal contraceptive. Interventions could also include the provision of a supplement versus a placebo. DATA COLLECTION AND ANALYSIS: We assessed for inclusion all titles and abstracts identified through the literature searches with no language limitation. The weighted mean difference (WMD) was computed with 95% confidence interval (CI) using a fixed-effect model. MAIN RESULTS: No trial had fracture as an outcome. Combination contraceptives did not appear to affect bone health. Of progestin-only methods, depot medroxyprogesterone acetate (DMPA) was associated with decreased bone mineral density, while results were inconsistent for implants. The two placebo-controlled trials showed BMD increases for DMPA plus estrogen supplement and decreases for DMPA plus placebo. AUTHORS' CONCLUSIONS: Whether steroidal contraceptives influence fracture risk cannot be determined from existing information. Due to different interventions, no trials could be combined for meta-analysis. Many trials had small numbers of participants and some had large losses to follow up. Health care providers and women should consider the costs and benefits of these effective contraceptives. For example, injectable contraceptives and implants provide effective, long-term birth control yet do not involve a daily regimen. Progestin-only contraceptives are considered appropriate for women who should avoid estrogen due to medical conditions.

Bone Density↗
PubMed1988

Fully effective contraception in male and female guinea pigs immunized with the sperm protein PH-20.

Immunization of male and female animals with extracts of whole sperm cells is known to cause infertility. Also, men and women who spontaneously produce antisperm antibodies are infertile but otherwise healthy. Although the critical sperm antigens are unknown, these observations have led to the proposal that sperm proteins might be useful in the development of a contraceptive vaccine. The guinea pig sperm surface protein PH-20 is essential in sperm adhesion to the extracellular coat (zona pellucida) of the egg, a necessary initial step in fertilization. Here, we report that 100% effective contraception was obtained in male and female guinea pigs immunized with PH-20. Antisera from immunized females had high titres, specifically recognized PH-20 in sperm extracts, and blocked sperm adhesion to the egg zona pellucida in vitro. The contraceptive effect was long-lasting and reversible: immunized females, mated at intervals of six to fifteen months after immunization, progressively regained fertility.

Animals↗
PubMed2003

Advance supply of emergency contraception. effect on use and usual contraception--a randomized trial.

OBJECTIVE: To evaluate whether advance provision of emergency contraception increases its use and/or adversely affects usual contraceptive practices. METHODS: We performed a randomized controlled trial comparing advance provision of emergency contraception with usual care in 370 postpartum women from an inner-city public hospital. Participants were followed for 1 year; 85% were available for at least one follow-up session. All participants received routine contraceptive education. The intervention group received a supply of emergency contraception (eight oral contraceptive pills containing 0.15 mg of levonorgestrel and 30 microg of ethinyl estradiol) and a 5-minute educational session. We compared use of emergency contraception and changes in contraceptive behaviors between groups. RESULTS: Women provided with pills were four times as likely to have used emergency contraception as women in the control group over the course of the year (17% versus 4%; relative risk [RR] 4.0; 95% confidence interval [CI] 1.8, 9.0). Women were no more likely to have changed to a less effective method of birth control (30% versus 33%; RR 0.92; 95% CI 0.63, 1.3), or to be using contraception less consistently (18% versus 25%; RR 0.74; 95% CI 0.45, 1.2). About half of each group reported at least one episode of unprotected intercourse during follow-up, but women who received emergency contraception were six times as likely to have used it (25% versus 4%; RR 5.8; 95% CI 2.1, 16.4). CONCLUSION: Advance provision of emergency contraception significantly increased use without adversely affecting use of routine contraception. It is safe and appropriate to provide emergency contraception to all postpartum women before discharge from the hospital.

Adult↗
PubMed2005

Norethisterone enanthate plus testosterone undecanoate for male contraception: effects of various injection intervals on spermatogenesis, reproductive hormones, testis, and prostate.

The goal of this study was to find the most favorable injection interval of norethisterone enanthate (NETE) plus testosterone undecanoate (TU) in terms of gonadotropin, sperm suppression, and prostatic effects. Fifty normal men were randomly assigned to receive NETE 200 mg plus TU 1000 mg every 8 wk (n = 10), every 12 wk (n = 10), every 6 wk for 12 wk and then every 12 wk (n = 10), and every 6 wk for 12 wk and thereafter TU 1000 mg plus placebo every 12 wk (n = 10), and placebo plus placebo every 6 wk for 12 wk and then every 12 wk (n = 10) for 48 wk. Semen analyses, blood drawings, physical examinations, and prostate ultrasounds were performed throughout the study. Of the men in the 8-wk injection group, 90% (nine of 10) achieved azoospermia, compared with 37.5% (three of eight) in the 12-wk injection group (P = 0.019). TU plus placebo injected every 12 wk did not maintain sperm suppression. Prostate volumes did not change significantly in either group. In conclusion, these data suggest that the combined administration of NETE and TU at 8-wk intervals represents an effective hormonal contraceptive regimen.

Adolescent↗
PubMed1998

Timing of onset of contraceptive effectiveness in Depo-Provera users. II. Effects on ovarian function.

OBJECTIVE: To determine the timing of onset of contraceptive effectiveness after the first injection of 150 mg of depot medroxyprogesterone acetate (DMPA) administered between days 8 and 13 of the menstrual cycle. DESIGN: Descriptive, prospective study. SETTING: A tertiary university referral center. PATIENT(S): Thirty healthy women between 18 and 40 years of age. INTERVENTION: Volunteers were injected with DMPA between days 8 and 13 (5 women on each day) of the menstrual cycle. MAIN OUTCOME MEASURE(S): Ovarian function determined by serum levels of E2 and progesterone and follicular development evaluated by vaginal ultrasound. RESULT(S): In nine (30%) of 30 women studied, DMPA did not prevent ovulation. All ovulations occurred in women receiving DMPA between days 10 and 13 of the cycle. No woman who received injections on day 8 or 9 ovulated. Ovulation suppression was more effective in women with low ovarian activity. All ovulation occurred within 3 days after the injection. CONCLUSION: A back-up contraceptive method, used after the 7th day of the menstrual cycle, is recommended for up to 7 days after the first injection of DMPA.

Adolescent↗
PubMedDate not supplied

The influence of community characteristics on the practice of effective contraception.

An analysis combining individual-level data from the National Survey of Family Growth with aggregate-level information provides evidence that the characteristics of communities influence the contraceptive decisions of currently married white women in the United States. The analysis examined the relationship between the average effectiveness level of the contraceptive methods that a woman used over a three-and-a-half-year period and community characteristics such as employment opportunities, the availability of contraceptive and abortion information and services, and the level of religious adherence in communities. Community characteristics associated with higher levels of contraceptive effectiveness were rapid population growth, high rates of unemployment, elevated levels of religious affiliation, high socioeconomic status, and ready access to family planning information and services. Community liberality was negatively associated with effective contraceptive use. The results support arguments that various community characteristics affect a woman's contraceptive choices by increasing or decreasing the costs of an unintended pregnancy.

Adolescent↗
PubMed1992

Effect of "missed" pills on oral contraceptive effectiveness.

OBJECTIVE: The purpose of this study was to determine whether missing pills in an oral contraceptive (OC) cycle resulted in folliculogenesis and eventual ovulation. METHODS: Fifteen women selected from a population requesting tubal reanastomosis were randomized into three groups and issued pill packs missing four consecutive pills in specific sequences, as follows: group I, days 1-4; group II, days 3-6; and group III, days 6-9. Serum was drawn for assay of LH, FSH, estradiol (E2), and progesterone, and serial ovarian ultrasound examinations were done to study follicular development throughout the cycle at 4-day intervals. RESULTS: No subject ovulated, as suggested by serum progesterone concentrations (not exceeding 0.63 ng/mL for any woman) and ultrasound assessment of follicular development (no follicular diameter exceeding 13 mm). The highest (mean +/- standard deviation) serum concentrations of LH and FSH in any group (13.25 +/- 18.71 and 14.40 +/- 7.71 mIU/mL, respectively) and of E2 (44.35 +/- 26.79 pg/mL) were observed during or immediately after the pill-free interval. Ovarian ultrasound examinations suggested suppressed folliculogenesis in all groups. No functional ovarian cysts were detected. CONCLUSIONS: Oral contraceptives exerted a similar degree of pituitary and ovarian suppression even when the subjects missed four pills at varying times in a cycle. The anovulatory effect persisted when the OC pills were reinstituted and taken reliably after an interval of noncompliance.

Adult↗