Contraceptive failure in the United States: estimates from the 1982 National Survey of Family Growth

A multivariate life-table analysis of national survey data from 1982 indicates that among currently married women, the pill and IUD have the lowest use-failure rates. During the first year of use, about three percent of pill users and six percent of IUD users experience an unintended pregnancy. Failure rates for the remaining methods range from 14 percent for the condom to 22 percent for spermicides; between these lie rhythm and natural family planning (16 percent), the diaphragm (17 percent) and other methods, mainly withdrawal, douche and abstinence. Married women using no contraceptive method experience an unintended pregnancy rate of 40 percent during the first year of unprotected intercourse. A woman's age, pregnancy intention (either to delay or to prevent births), parity and income all have significant effects on the risk of unintended pregnancy. The risk generally declines with age, except for women attempting to prevent an unwanted pregnancy, among whom women under 20 have lower failure rates than do those 20-29 years of age. As expected, women attempting to prevent an unwanted pregnancy have lower failure rates than do those seeking to delay a wanted pregnancy, with the difference being greatest for women under 20 years of age and smallest for 20-29-year-olds. Use-failure rates among low-income women are higher than those among women with larger family incomes, while low-parity women have lower failure rates than do women of higher parity. On average, standardized use-failure rates for single women are lower than those for married women, probably because of a lower average level of intercourse among single women. In addition, these rates are understated because of the substantial underreporting of abortion among single women; if abortion reporting were complete, failure rates would be about 1.4 times as high as they appear here, and thus would be close to those of married women. Differences in the risk of unintended pregnancy among single women show a number of similarities with those seen among married women: Use of the pill and IUD is associated with the lowest failure rates, reliance on the condom is associated with intermediate failure rates, and use of spermicides is linked with the highest failure rates. However, while rhythm and the diaphragm exhibit use-failure rates that are among the highest found for single women, failure rates for these methods are at intermediate levels among married women.(ABSTRACT TRUNCATED AT 400 WORDS)     

Contraceptive failure in the United States: revised estimates from the 1982 National Survey of Family Growth

It is estimated that only about half of all abortions occurring during the period covered by the 1982 National Survey of Family Growth were actually reported in the survey; thus, contraceptive failure rates calculated from these data are almost certainly inaccurate. An attempt to correct for the underreporting of abortion indicates that actual 12-month use-failure rates are more than one-third higher than those calculated without taking abortion underreporting into account, with rates ranging from six percent for the pill to 14-16 percent for the condom, diaphragm and rhythm and to 26 percent for spermicides. Patterns of contraceptive failure are similar to those found in earlier studies.     

Vasectomy: the other (better) form of sterilization

Male sterilization (vasectomy) is the most effective form and only long-acting form of contraception available to men in the United States. Compared to female sterilization, it is more efficacious, more cost-effective, and has lower rates of complications. Despite these advantages, in the United States, vasectomy is utilized at less than half the rate of female sterilization. In addition, vasectomy is least utilized among black and Latino populations, groups with the highest rates of female sterilization. This review provides an overview of vasectomy use and techniques, and explores reasons for the disparity in vasectomy utilization in the United States.     

Contraceptive discontinuation among married women in the United States

Using data from the 1982 National Survey of Family Growth (NSFG), this analysis reports differentials in contraceptive discontinuation among married women aged 15-44 years in the United States. The total discontinuation rate is broken down into change to no method (termination) or to a different method (a method switch), and rates are obtained for specific methods. In addition, sociodemographic differences in risks associated with each type of discontinuation are shown. Discontinuation rates are compared to use-failure rates to provide a more comprehensive understanding of the implications of discontinuation for contraceptive efficacy.     

Probability of pregnancy after sterilization: a comparison of hysteroscopic versus laparoscopic sterilization

Objective

To compare the expected probability of pregnancy after hysteroscopic versus laparoscopic sterilization based on available data using decision analysis.

Study design

We developed an evidence-based Markov model to estimate the probability of pregnancy over 10 years after three different female sterilization procedures: hysteroscopic, laparoscopic silicone rubber band application and laparoscopic bipolar coagulation. Parameter estimates for procedure success, probability of completing follow-up testing and risk of pregnancy after different sterilization procedures were obtained from published sources.

Results

In the base case analysis at all points in time after the sterilization procedure, the initial and cumulative risk of pregnancy after sterilization is higher in women opting for hysteroscopic than either laparoscopic band or bipolar sterilization. The expected pregnancy rates per 1000 women at 1 year are 57, 7 and 3 for hysteroscopic sterilization, laparoscopic silicone rubber band application and laparoscopic bipolar coagulation, respectively. At 10 years, the cumulative pregnancy rates per 1000 women are 96, 24 and 30, respectively. Sensitivity analyses suggest that the three procedures would have an equivalent pregnancy risk of approximately 80 per 1000 women at 10 years if the probability of successful laparoscopic (band or bipolar) sterilization drops below 90% and successful coil placement on first hysteroscopic attempt increases to 98% or if the probability of undergoing a hysterosalpingogram increases to 100%.

Conclusion

Based on available data, the expected population risk of pregnancy is higher after hysteroscopic than laparoscopic sterilization. Consistent with existing contraceptive classification, future characterization of hysteroscopic sterilization should distinguish “perfect” and “typical” use failure rates.

Implications

Pregnancy probability at 1 year and over 10 years is expected to be higher in women having hysteroscopic as compared to laparoscopic sterilization.     

Childlessness in the United States: estimates from the National Survey of Family Growth

Using a representative sample of about 17,000 ever married women 15 to 44 years of age, this article presents national estimates of the prevalence and correlates of voluntary, involuntary, and temporary childlessness in the United States. These three groups of childless couples are compared with the parents of small planned families and other parents on a number of social, economic, marital, and family characteristics. When viewed cross sectionally, voluntarily childless couples constitute between 1.3% and 1.8% of currently married couples, depending on the definitions used. They are a distinctive but rare population. Their future prevalence depends primarily on the decisions of the large group of temporarily childless couples.     

Contraceptive failure, method-related discontinuation and resumption of use: results from the 1995 National Survey of Family Growth

This study computed life table probabilities of contraceptive failure, discontinuation of use, and return to contraceptive use in the US. Data were obtained from the 1995 National Survey of Family Growth (NSFG) among a nationally representative sample of 6867 contraceptive use intervals contributed by women 15-45 years old who began use or resumed use after discontinuation during 1991-95. Analysis was based on Kaplan-Meier product-limit single decrement life table probability methods. Findings indicate that the risk of failure during typical use of reversible methods was 9% within 1 year of starting. Women with continuous lifetime use will experience 1.8 contraceptive failures. Failure rates were 7% for the pill, 9% for the male condom, 8% for the diaphragm, 20% for periodic abstinence, and 15% for spermicides. Failure rates reflect imperfect use. 31% of women discontinued use within 6 months of starting use. 44% discontinued within 12 months. Women using reversible methods continuously will discontinue use nearly 10 times during the reproductive period. Most women resumed use shortly after discontinuation. Low income women had higher risk of unintended pregnancy for all methods and the pill and lower risk of resumption after discontinuation. Hispanics had a higher risk of contraceptive failure for all methods and the condom. Black women had a higher risk of discontinuation of oral pills and condoms.     

Contraceptive use by disability status: new national estimates from the National Survey of Family Growth

Objective

The objective was to determine population-based estimates of use of contraception among women 15–44?years of age in the United States by disability status.

Sex education and contraceptive use at coital debut in the United States: results from Cycle 6 of the National Survey of Family Growth

Background

The study was conducted to characterize the relationship between formal sex education and the use and type of contraceptive method used at coital debut among female adolescents.

Methods

This study employed a cross-sectional, nationally representative database (2002 National Survey of Family Growth). Contraceptive use and type used were compared among sex education groups [abstinence only (AO), birth control methods only (MO) and comprehensive (AM)]. Analyses also evaluated the association between demographic, socioeconomic, behavioral variables and sex education. Multiple logistic regression with adjustment for sampling design was used to measure associations of interest.

Results

Of 1150 adolescent females aged 15-19 years, 91% reported formal sex education (AO 20.4%, MO 4.9%, AM 65.1%). The overall use of contraception at coitarche did not differ between groups. Compared to the AO and AM groups, the proportion who used a reliable method in the MO group (37%) was significantly higher (p=.03) (vs. 15.8% and 14.8%, respectively).

Conclusions

Data from the 2002 NSFG do not support an association between type of formal sex education and contraceptive use at coitarche but do support an association between abstinence-only messaging and decreased reliable contraceptive method use at coitarche.     

Fertility and family planning in the United States: insights from the National Survey of Family Growth

A review of about 50 studies based on the 1982 National Survey of Family Growth (NSFG) illustrates the ways in which the survey sheds new light on trends and differentials in such areas as fertility, contraceptive use, infertility and the use of family planning services in the United States. The total fertility rate declined by nearly 50 percent between 1960 and 1973, from 3.6 to 1.9 births per woman, and changed little from then until 1982. It would appear that growing use of the pill, the IUD and sterilization--but principally the pill--is the prime factor in the dramatic decline in unwanted and mistimed births among married couples. Their increasing reliance on sterilization between 1973 and 1982 reduced the proportion of unwanted births at ages 35 or older by half, but had little impact on overall birthrates because only about five percent of all births occurred at those ages in 1981. Although overall fertility has declined, the rate of premarital pregnancy has risen since the early 1960s. Research based on the NSFG suggests that this is a result both of the rapid increase in the percentage of women who have premarital intercourse and of the increasing length of exposure to premarital pregnancy. The latter trend is probably related both to earlier intercourse and to delayed marriage. Despite the increasing levels of premarital exposure, however, there was actually a decline in teenage birthrates in the 1970s, which was due in part to the rising abortion rates among teenagers. Finally, although racial differences in fertility have narrowed, black women still have higher fertility than whites. The 1982 NSFG data suggest that four factors are principally responsible for the higher birthrates of black women: Blacks begin having intercourse earlier than whites; black women are one-third less likely to use contraceptives at first intercourse; they are more likely to be currently exposed to the risk of unplanned pregnancy and not using a method; and they have higher pregnancy rates when they are using no contraceptives or less-effective methods, such as the condom, rhythm and withdrawal.     

Contraceptive effectiveness of two insertions of quinacrine: results from 10-year follow-up in Vietnam

BACKGROUND: This study was conducted to evaluate the long-term effectiveness of two insertions of quinacrine pellets for nonsurgical sterilization among women in northern Vietnam. STUDY DESIGN: Observational cohort study of 1335 women who received two quinacrine insertions between 1989 and 1993. RESULTS: About 90% of the study population participated in the last round of interviews. Cumulative follow-up time for this cohort was 14,294 person-years. The 1-, 5- and 10-year cumulative pregnancy probabilities for quinacrine were 3.3% (95% CI, 2.4-4.3), 10.0% (95% CI, 8.4-11.6) and 12.1% (95% CI, 10.4-13.9), respectively. Pregnancy estimates with quinacrine in this cohort were higher than that reported from US-based research on surgical tubal sterilization and higher than results of quinacrine sterilization in Chile. Quinacrine effectiveness was better among older women. CONCLUSION: The effectiveness of quinacrine in Vietnam was lower than other forms of sterilization. Factors such as inconsistent training and use of various insertion techniques may have contributed to the relatively high failure rate.     

Contraceptive failure rates: new estimates from the 1995 National Survey of Family Growth

CONTEXT: Unintended pregnancy remains a major public health concern in the United States. Information on pregnancy rates among contraceptive users is needed to guide medical professionals' recommendations and individuals' choices of contraceptive methods. METHODS: Data were taken from the 1995 National Survey of Family Growth (NSFG) and the 1994-1995 Abortion Patient Survey (APS). Hazards models were used to estimate method-specific contraceptive failure rates during the first six months and during the first year of contraceptive use for all U.S. women. In addition, rates were corrected to take into account the underreporting of induced abortion in the NSFG. Corrected 12-month failure rates were also estimated for subgroups of women by age, union status, poverty level, race or ethnicity, and religion. RESULTS: When contraceptive methods are ranked by effectiveness over the first 12 months of use (corrected for abortion underreporting), the implant and injectables have the lowest failure rates (2-3%), followed by the pill (8%), the diaphragm and the cervical cap (12%), the male condom (14%), periodic abstinence (21%), withdrawal (24%) and spermicides (26%). In general, failure rates are highest among cohabiting and other unmarried women, among those with an annual family income below 200% of the federal poverty level, among black and Hispanic women, among adolescents and among women in their 20s. For example, adolescent women who are not married but are cohabiting experience a failure rate of about 31% in the first year of contraceptive use, while the 12-month failure rate among married women aged 30 and older is only 7%. Black women have a contraceptive failure rate of about 19%, and this rate does not vary by family income; in contrast, overall 12-month rates are lower among Hispanic women (15%) and white women (10%), but vary by income, with poorer women having substantially greater failure rates than more affluent women. CONCLUSIONS: Levels of contraceptive failure vary widely by method, as well as by personal and background characteristics. Income's strong influence on contraceptive failure suggests that access barriers and the general disadvantage associated with poverty seriously impede effective contraceptive practice in the United States.     

Reconsidering racial/ethnic differences in sterilization in the United States

Objective

Cross-sectional studies have found that low-income and racial/ethnic minority women are more likely to use female sterilization and less likely to rely on a partner’s vasectomy than women with higher incomes and whites. However, studies of pregnant and postpartum women report that racial/ethnic minorities, particularly low-income minority women, face greater barriers in obtaining a sterilization than do whites and those with higher incomes. In this paper, we address this apparent contradiction by examining the likelihood a woman gets a sterilization following each delivery, which removes from the comparison any difference in the number of births she has experienced.

Study Design

Using the 2006–2010 National Survey of Family Growth, we fit multivariable-adjusted logistic and Cox regression models to estimate odds ratios and hazard ratios for getting a postpartum or interval sterilization, respectively, according to race/ethnicity and insurance status.

Results

Women’s chances of obtaining a sterilization varied by both race/ethnicity and insurance. Among women with Medicaid, whites were more likely to use female sterilization than African Americans and Latinas. Privately insured whites were more likely to rely on vasectomy than African Americans and Latinas, but among women with Medicaid-paid deliveries reliance on vasectomy was low for all racial/ethnic groups.

Conclusions

Low-income racial/ethnic minority women are less likely to undergo sterilization following delivery compared to low-income whites and privately insured women of similar parities. This could result from unique barriers to obtaining permanent contraception and could expose women to the risk of future unintended pregnancies.

Implications

Low-income minorities are less likely to undergo sterilization than low-income whites and privately insured minorities, which may result from barriers to obtaining permanent contraception, and exposes women to unintended pregnancies.     

Discontinuation and resumption of contraceptive use: results from the 2002 National Survey of Family Growth

BACKGROUND: Discontinuation of contraceptive use that is not immediately followed by resumption of use of another method while a woman is at risk is a common cause of unintended pregnancy. STUDY DESIGN: We provide new estimates of discontinuation for the pill, injectable, male condom, withdrawal and fertility-awareness-based methods, and identify socioeconomic characteristics associated with discontinuation for the pill, male condom and withdrawal. We provide new estimates of resumption of use by prior method used and identify socioeconomic characteristics associated with resumption of use. Estimates are obtained using the 2002 National Survey of Family Growth, supplemented by the 2001 Abortion Patient Survey to correct for underreporting of abortion. RESULTS: The fraction of method use segments discontinued for method-related reasons within 1 year was highest for the male condom (57%), withdrawal (54%) and fertility-awareness-based methods (53%), and lowest for the pill (33%), with the injectable in-between (44%). However, contraception was abandoned altogether in only 25% of cases. The probability of resuming use of a contraceptive was 72% in the initial month of exposure to the risk of an unintended pregnancy; this rose to 76% by the third month. CONCLUSION: The risk of discontinuation of use of reversible methods of contraception for method-related reasons, including a change of method, is very high, but fortunately the risk of abandoning use of contraception altogether is far lower, and most spells of exposure to risk of an unintended pregnancy following discontinuation are protected from the start by a switch to another method.     

The use of a low-literacy version of the Medicaid sterilization consent form to assess sterilization-related knowledge in Spanish-speaking women: results from a randomized controlled trial

Objective

To learn whether a version of the Medicaid Sterilization Consent Form (SCF) adapted for populations of low-literacy can help Spanish-speaking women better understand the process and consequences of tubal sterilization.

The safety,efficacy and acceptability of task sharing tubal sterilization to midlevel providers: a systematic review

Background

Task sharing is an important strategy for increasing access to modern, effective contraception for women and reducing unmet need for family planning.

Objective

The objective was to identify evidence for the safety, efficacy or acceptability of task sharing tubal sterilization to midlevel providers.

Search strategy

We searched PubMed, Cochrane and Popline for articles in all languages using the following key words: task sharing, tubal sterilization, midlevel providers, task shifting.

Selection criteria

All studies reporting on any measure of safety, efficacy or acceptability of tubal sterilization performed by any cadre of midlevel providers.

Data collection and analysis

Data were independently abstracted by two authors and graded using the United States Preventive Services Task Force rating for evidence quality. Heterogeneity of outcome measures precluded a meta-analysis.

Main results

Nine studies of fair to poor quality reported on safety and acceptability outcomes. Generalizability of findings is limited by inadequate sample size and lack of statistical comparisons. No study reported on long-term efficacy outcomes.

Conclusions

Well-designed clinical trials, of adequate sample size, are urgently needed to establish the safety, efficacy and acceptability of task sharing tubal sterilization to midlevel providers.