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At least 19 recordsLinked to original sources
PubMed1979

Use-effectiveness and client satisfaction in six centers teaching the Billings Ovulation Method.

Use-effectiveness of the Billings Ovulation Method (OM) is reported for 1139 clients from six centers who were followed for at least 24 months. Method failure rates were 1% when calculated by either Pearl formula or life table analysis. Combined method and user failure rates were 20% when calculated with the Pearl formula, and 16% at 12 months and 23% at 24 months by life table analysis. Pregnancy rates were higher for couples using OM alone, than for couples using OM in combination with additional fertility awareness methods or together with barrier methods. The difference was significant when estimated by the Pearl formula but not when analyzed by the life table. The emotional implications underlying the apparent contradiction between a desire to avoid pregnancy and the deliberate coital use of fertile days are reflected in the differences between method and user failure rates, the high client satisfaction levels reported with "user failure," and 56% continuation rate at 24 months. The will require in-depth exploration.

Abortion, Legal↗
PubMed1985

Barrier contraception in the teenager: a comparison of four methods in adolescent girls.

The use-effectiveness and continuation rates of 4 methods of contraception were studied during a 2 year follow-up period in a group of 405 teenage girls. Results were compared in 2 groups of adolescents, 1 of highly motivated, high socioeconomic status girls (A) and 1 of poorly motivated, low socioeconomic status adolescent clinic patients (B). The method of contraception was selected by the girls, who were instructed in their proper use. Results showed good rates of continuation among girls of the 1st group as compared to those of the 2nd group. Pregnancy rates after 24 months of use, as calculated by Pearl's formula, was 3.6 and 5.4 respectively with the use of a condom, and 5.8 and 10.8 when the diaphragm was used. When using vaginal foam alone, the rates were 4.2 and 12.3 and with the rhythm method, 8.5 and 13.1. The foam-alone method was unpopular in both groups. No serious side effects or complications were recorded. The study demostrated a reasonable acceptability and use-effectiveness for barrier contraceptives. It is suggested that these harmless and complication-free methods, especially the condom and diaphragm, may be reasonable alternatives for the more modern methods in teens of all socioeconomic strata; an effort must be made to educate and instruct the poorly motivated and encourage them to present themselves for regular follow-up.

Adolescent↗
PubMed1989

The vaginal contraceptive diaphragm and the condom--a reevaluation and comparison of two barrier methods with the rhythm method.

The use-effectiveness and continuation rates of two barrier methods of contraception, the diaphragm and condom, were studied during a two-year follow-up in a group of 85 and 98 women, respectively. All were highly motivated. Results were compared to a group of 64 women using the periodic abstinence or rhythm method, i.e. not using any contraceptive. The patients selected the method of contraception they preferred and were instructed in their proper use. Results showed good continuation rates in the groups using a diaphragm and the condom for 2 years, for a total follow-up of 5570 cycles. Pregnancy rate after 24 months of use, as calculated by Pearl's formula, was 2.48 for the diaphragm, 3.21 for the condom, and 5.19 in the rhythm group. No serious side effects or complications occurred in either group. The study demonstrated a fair acceptability and use-effectiveness for barrier contraceptive. We suggest that these harmless and complication-free methods may still be reasonable alternatives for the "modern" methods, the pill and the IUD.

Adolescent↗
PubMed2026

Axial Length Adjustment and AL/R Ratio Optimization of IOL Power Calculation in Extremely Long Eyes.

PURPOSE: To evaluate the accuracy of modern intraocular lens (IOL) power calculation formulas and axial length (AL) adjustment methods in eyes with AL ≥ 30.0 mm. DESIGN: Retrospective consecutive cross-sectional study. PARTICIPANTS AND CONTROLS: A total of 308 eyes (308 patients) with AL ≥ 30.00 mm were included. METHODS: Accuracy of modern online formulas, alone or with established AL adjustments methods, was analyzed. Subgroup analyses were performed based on AL, keratometry (K), anterior chamber depth (ACD), lens thickness (LT), and AL-to-corneal radius (AL/R) ratio. MAIN OUTCOME MEASURES: Predictive accuracy was evaluated using the formula performance index (FPI), root mean square absolute prediction error (RMSAE), standard deviation (SD) of prediction error (PE), and percentage of eyes within ±0.25 and ±0.50 diopters (D). RESULTS: Overall, Holladay 1 combined with the nonlinear polynomial Wang-Koch axial length adjustment (H1-PWK) demonstrated the best overall performance, achieving the lowest SD (0.40), RMSAE (0.40), and highest FPI (0.494). A tendency toward hyperopic error was observed in eyes with AL ≥ 32.0 mm, K ≥ 46.0 D. The AL/R ratio showed a significant positive correlation with PE in the Ladas Super formula, Barrett Universal II, EVO, PEARL-DGS, and Hoffer QST formulas. Spline-based regression analysis indicated that the transition point of AL/R from myopic to hyperopic PE varied across different formulas. CONCLUSIONS: H1-PWK provides robust refractive accuracy in extremely long eyes. The AL/R ratio may provide a useful composite biometric stratification parameter compared to AL alone.

Humans↗
PubMed1981

A randomized prospective study of the use-effectiveness of two methods of natural family planning.

The final results of a prospective comparative study of two methods of natural family planning indicate a significant difference in the 12 month net cumulative pregnancy rates between the ovulation and symptothermal methods. These differences are on the order of two to one in favor of the symptothermal method. Pearl pregnancy rates confirm similar differentials between the two methods. Dropout rates for both methods were high. Lack of interest or dissatisfaction with the method was the major reason for dropout training while pregnancy or desire for pregnancy were the major reasons for dropout during the formal phase of the study.

Adult↗
PubMed1992

Norgestimate: a clinical overview of a new progestin.

The efficacy and safety of a new monophasic oral contraceptive, norgestimate/ethinyl estradiol, containing the third-generation progestin, norgestimate (250 micrograms), and ethinyl estradiol (35 micrograms), are reviewed. Norgestimate/ethinyl estradiol demonstrates excellent contraceptive efficacy, with a Pearl index of 0.25. Cycle control is reliable, with a low incidence of breakthrough bleeding and spotting. Because of the minimal androgenicity of norgestimate, norgestimate/ethinyl estradiol has a low impact on carbohydrate and lipid metabolism. It neither reduces the vasodilatory and antiaggregatory prostacyclin nor increases its endogenous antagonist, thromboxane. Norgestimate/ethinyl estradiol has no significant effect on blood coagulation factors. All these characteristics suggest that norgestimate/ethinyl estradiol may be associated with a lower risk of cardiovascular disease than other oral contraceptives currently available. Epidemiologic data, however, are not available, and physicians should be reluctant to prescribe it or any oral contraceptive to patients who have a history of vascular or thrombotic disorders.

Female↗
PubMed1993

Contraceptive efficacy of a monophasic oral contraceptive containing desogestrel.

Desogestrel, a new gonane progestin, has been shown to be comparable in efficacy with oral contraceptives currently in use in the United States. Results from several large efficacy studies conducted in Europe encompassing 42,640 patients in 183,212 cycles resulted in six pregnancies for a Pearl index of 0.04. This low rate, which was compared with those observed in recent U.S. clinical trials, reflects differences in study methodology. An additional indicator of an oral contraceptive's efficacy is its ability to suppress ovarian function, including follicular development and increases in plasma estradiol levels. Desogestrel has been found to be among the strongest suppressors of ovarian activity.

Contraceptives, Oral↗
PubMed1986

Contraception with the cervical cap: effectiveness, safety, continuity of use, and user satisfaction.

With the growing interest in barrier contraceptive methods, the cervical cap has come back into use in North America. We examined the cap's effectiveness, safety, continuity of use, and user satisfaction among 617 women who were fitted at a family planning clinic in Toronto, Canada, between May 1981 and November 1983. Follow-up information was available for 516 of these women. Using a life table analysis with Bayesian adjustment, the probability of becoming pregnant after 12 months of use was 0.166 with a standard error of 0.022. There is evidence that after 1 year of use the caps deteriorate and that this deterioration may increase the risk of pregnancy. Many of the women in this study were very satisfied with the cervical cap; however, such problems as dislodgement, discomfort to user and partner, difficulty with insertion and removal, and unpleasant odour affected acceptability and continuity of use. It is likely that these problems could be alleviated by improving the quality of or changing the materials, modifying the design to improve the fit, and providing a greater range of sizes.

Adolescent↗
PubMed1988

Use-effectiveness of the ovulation method initiated during postpartum breastfeeding.

Between April 1981 to March 1984, 419 urban middle class postpartum women entered the Natural Family Planning (NFP) program of the Pontificia Universidad Catolica de Chile. This NFP program teaches the Ovulation Method (Billings). Only 1.9% of the women did not learn how to recognize the mucus pattern of fertility awareness. The sample of 378 women who were practicing the method to avoid a pregnancy completed 4,935 months of use of the OM. The cumulative life table unplanned pregnancy rate at the 12th postpartum month was 11.1 +/- 1.9 and the Pearl Rate was 12.1 per 100 woman-years. The Pearl Rate calculation of method-related failure was only 2.1 pregnancies per 100 woman-years. The breastfeeding group showed a significantly lower rate of unplanned pregnancies than the nonbreastfeeding group and there was no significant increase in unplanned pregnancy at the time of menstruation among previously amenorrheic women as compared to later intervals. The protection against unplanned pregnancy shown in this study should be viewed as the combination of two factors: breastfeeding and the Ovulation Method (OM) of NFP.

Adult↗
PubMed1991

Clinical experience with a modern low-dose oral contraceptive in almost 100,000 users.

Efficacy, cycle control, tolerance, and adverse events were studied in a clinical Phase IV study using a new progestogen, gestodene, in an amount of 75 micrograms combined with 30 micrograms ethinylestradiol. The study was performed as a multicenter trial in 96,000 patients over a period of 6 cycles. Half of the patients taking the new preparation were first-time OC users, the other half switched from another OC. With regard to contraceptive efficacy, the life-table analysis showed a value of 0.032% for method failure and 0.114% for patient failure. The correspondent Pearl-Index is 0.062 and 0.22. The new drug was found acceptable by more than 90% of the women involved in the trial. Dysmenorrhea present in the "switchers" mostly disappeared on the new OC, while body weight and blood pressure remained virtually unchanged. Thus, it can be concluded that blood pressure and body weight behaviour is similar to that seen with other low-dose OCs. The new combined pill offers excellent cycle stability and has a very favourable effect on dysmenorrhea. The number of clinically diagnosed thrombotic events documented in this study was 0.65 per 1000 woman-years (TWY) and does not exceed the range of events seen in groups of women using non-hormonal methods of contraception (Oxford-FPA study 0.4/TWY and RCGP study 0.8/TWY).

Adult↗
PubMed1993

Ultrasound evaluation of ovarian activity under oral contraceptives.

The trend towards changing the composition of the contraceptive pill in order to decrease side effects might lead to increased ovarian activity. This may decrease reliability. Therefore, a non-invasive method for monitoring the suppressive effect of the pill on ovarian function is warranted. The aim of the present study was to investigate whether or not diagnostic ultrasound might be the method of choice for studying residual ovarian activity during pill use. In 89 women on a low-dose oral contraceptive (30 mcg ethinyl-estradiol (EE)/75 mcg gestodene), the first two months of pill-intake were monitored extensively with diagnostic ultrasound. The study revealed that only one ultrasound investigation was needed during the first week of pill intake to discover all relevant cases of residual ovarian activity. Follow-up investigations are needed to quantify this activity more specifically.

Contraceptives, Oral↗
PubMed1983

The safety and efficacy of tubal sterilization: an international overview.

This article presents a synthesis of some of the major published studies on the efficacy and safety of tubal sterilization. The conclusions of this overview are that tubal sterilization is a safe operation, long-term sequelae of tubal sterilization have not been well documented, and the risk of pregnancy following tubal sterilization is less than 1 in 100. Continued study is needed to determine how to make a safe and effective procedure even safer and more effective.

Female↗
PubMed1991

Natural family planning: looking ahead.

Natural family planning is used by a relatively small number of people worldwide. The Institute's goal is to increase the knowledge, availability, effectiveness, and acceptability of natural family planning. To do so, the Institute is conducting biomedical research in several areas including: (1) the development of a home test kit for ovulation prediction, (2) sperm-mucus interaction, (3) the mechanisms and fertility impact of lactational amenorrhea, and (4) outcome of pregnancies in natural family planning users.

Amenorrhea↗
PubMed1991

Use of the Home Ovarian Monitor in pregnancy avoidance.

The application of the Home Ovarian Hormone Monitor to the avoidance of pregnancy by periodic abstinence has been explored. No woman had difficulty with the daily urine testing, and their results consistently identified the distinctive hormone pattern of the ovulatory cycle and the day of ovulation and correlated closely with the mucus symptoms. The tests gave 4 days or more warning of ovulation in 99% of cycles and allowed intercourse to be resumed 1 to 3 days after ovulation in 88%, giving a mean period of abstinence of 7 days. No pregnancy occurred from intercourse during the late safe days defined by the Monitor, but some early-day pregnancies occurred through long sperm survivals of 6 to 8 days, mostly during the return of fertility after breastfeeding. Rules for the avoidance of pregnancy, with the minimum of testing on the basis of these results, are given.

Adult↗
PubMed1991

Efficacy studies in natural family planning: issues and management implications illustrated with data from five studies.

Studies of method effectiveness must be carefully assessed for comparability of findings. Several parameters are identified that are important in the assurance of comparable results. This article discusses these issues with the use of data from previously published studies and emphasizes the management implications of use-effectiveness data.

Data Interpretation, Statistical↗
PubMed1991

Further analysis of contraceptive failure of the ovulation method.

Reanalysis of data on the ovulation method of natural family planning collected by the World Health Organization yields the following conclusions. The method is effective during perfect (correct and consistent) use, with a first-year probability of failure of 3.4%. However, it is extremely unforgiving of imperfect use, with a first-year probability of failure of 84.2% if the method is not used correctly. During the initial year, 87% of the cycles were characterized by perfect use. Nevertheless, the 13% of cycles characterized by imperfect use had a tremendous impact on the overall failure rate. During the first year of typical use 22.5% of the women in the clinical trial became accidentally pregnant.

Adult↗