Obesity and oral contraceptive pill failure

[Contraception in women with obesity]

Obese women are at high risk of unintended pregnancy. In addition, obesity is an important risk factor for venous thromboembolism events and arterial thrombosis. All of these data are to be considered in choosing a contraceptive method for obese women. The metabolic changes and the increased body mass of these women may be the cause of a reduction in the effectiveness of hormonal contraception. The progestin-only contraceptives (progestin only pills and etonogestrel subdermal implant) and the intra-uterine devices are the preferred contraceptive methods in women with obesity. The combined estrogen-progestin contraceptives may be proposed in young obese women without other cardiovascular risk factor. Obesity per se does not seem to increase the risk of failure of most contraceptive methods. Bariatric surgery is a complex situation. Contraception is needed for at least 12 months after surgery. Some bariatric surgery such as bypass can induce gastrointestinal malabsorption. In this situation, all oral contraceptives are not recommended because of a higher risk of failure.

The association between combined oral contraceptive use and overweight/obesity: a secondary data analysis of the 2016 Ethiopia Demographic and Health Survey

OBJECTIVES

In this study, we aimed to assess the association between combined oral contraceptive (OC) use and overweight/obesity among Ethiopian adult women of reproductive age.

DESIGN, SETTING AND PARTICIPANTS

The data were extracted from the 2016 Ethiopia Demographic and Health Survey; these data were collected from nine regions and two city administrations. We analysed the data from a total of 11 018 women aged 18-49 years who met eligibility criteria.

MAIN OUTCOME MEASURES

We employed WHO criteria to classify the body mass index of women. Specifically we tested the association between combined OC utilisation with overweight/obesity after controlling for confounding variables.

RESULT

The prevalence of combined OC utilisation was 1.7% and the prevalence of overweight/obesity was 8.6% among adult women of reproductive age. Use of combined OC increases the odds of overweight/obesity by two times among adult women of reproductive age after controlling for potential confounders (adjusted OR=1.902 (1.064-3.399)).

CONCLUSION

In conclusion there is significant association between combined OC use and overweight/obesity. The findings have important implications for policymakers to design evidence based policy approachs to obesity prevention for women and at large for government to recognise the negative consequences of combined OC on women health.

Obesity and contraceptive use among women 20-44years of age in the United States: results from the 2011-15 National Survey of Family Growth (NSFG)

OBJECTIVE

Obesity has increased dramatically in the United States in recent decades. Our objective was to explore associations of contraceptive choices of US women, aged 20-44years, with body mass index (BMI) and relevant covariates.

STUDY DESIGN

Data are based on interviews with a national sample of 11,300 women in the 2011-2015 National Survey of Family Growth. We analyzed women ages 20-44 at risk of unintended pregnancy. The primary dependent variable was BMI category. Covariates analyzed included age, parity, race/ethnicity, marital status, self-reported health and education. Data were analyzed via cross-tabulation and logistic regression. We determined unadjusted and adjusted odds ratios for three categories of contraceptive method: female sterilization, intrauterine device (IUD) and hormonal contraception.

RESULTS

Obese women have higher odds of female sterilization (BMI 30.0-34.9 kg/m²: adjusted odds ratio (aOR)=1.96, 95% confidence interval (CI) 1.45-2.66; BMI 35.0 kg/m² and higher: aOR=1.56, 95% CI 1.13-2.14) compared to women with normal BMI. Odds of IUD use are significantly higher among women with BMI >35 kg/m² (aOR=1.64, 95% CI 1.20-2.25). Odds of hormonal contraceptive use are correspondingly reduced (aOR=0.78, 95% CI 0.62-0.98) for women in the highest BMI category.

CONCLUSIONS

Contraceptive use varies by BMI category even after adjusting for usual correlates of use. Differences in contraceptive use by BMI category have implications for contraceptive counseling and provision.

IMPLICATIONS

Findings that obese women are more likely to rely on female sterilization raise questions about how weight concerns and obesity affect contraceptive decision making. Future research could explore associations between obesity and contraceptive use in adolescent women.

Healthcare Provider Attitudes Regarding Contraception for Women with Obesity

BACKGROUND

Whether providers who regularly provide family planning services consider contraceptive methods as unsafe for women with obesity is unknown.

METHODS

We analyzed questionnaire responses received from December 2009 to March 2010 from 635 office-based physicians and 1323 Title X clinic providers delivering family planning services, who were randomly sampled (response rate 65%) before the release of national evidence-based contraception guidelines. We examined provider and clinical setting characteristics and clinic patient demographics for association with provider misconceptions about safety of combined oral contraceptives (COCs), depot medroxyprogesterone acetate (DMPA), or intrauterine devices (IUDs) for women with obesity. If providers considered methods as unsafe or do not know, we categorized those responses as misconceptions. We used multivariable logistic regression to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs).

RESULTS

A substantial proportion of respondents had misconceptions about the safety of COCs (31%), DMPA (24%), copper (Cu) (18%), and levonorgestrel (LNG)-IUDs (16%) for women with obesity. Provider type was associated with increased odds of misconceptions for all four methods compared with office-based obstetrician/gynecologists. Not having the method available onsite was associated with safety misconceptions of DMPA (aOR 1.90, 95% CI 1.07-3.36), Cu-IUD (aOR 4.19, 95% CI 1.51-11.61), and LNG-IUD (aOR 5.25, 95% CI 1.67-16.49).

CONCLUSION

While the majority of providers considered all four contraceptive methods safe for women with obesity, substantial proportions had misconceptions about safety of COCs, DMPA, and IUDs. Provider education, particularly among certain specialties, is needed to increase knowledge regarding moderate and highly effective contraceptive methods among this patient population.

Depo-Provera (depot medroxyprogesterone acetate) use after bariatric surgery

In the US, obesity rates are increasing greatly. The Centers for Disease Control and Prevention estimates that 68.5% of Americans, including 63.9% of adult women older than 20 years, are overweight (body mass index between 25 kg/m² and 29.9 kg/m²) or obese (body mass index >30 kg/m²). In light of this, it is not surprising that the rates of bariatric surgery have also been increasing. When considering the metabolic changes associated with both bariatric surgery and contraceptive use, in combination with the unique medical considerations of obese women, it is indisputable that clear guidelines are needed when counseling obese patients of reproductive age after bariatric surgery. In this literature review, we focus on depot medroxyprogesterone acetate (DMPA) and the implications of its use in obese women, preweight and postweight loss following bariatric surgery. Both DMPA use and bariatric surgery are known to cause bone loss, but it is still unclear whether there is an additive effect of the two factors on bone loss and whether either of these factors directly leads to an increased risk of bone fracture. The current consensus guidelines do not impose a restriction on the use of DMPA after bariatric surgery. DMPA use is associated with weight gain, and it is unclear whether weight loss blunting occurs with the use of DMPA after bariatric surgery. Prior studies had demonstrated an association with weight gain in adolescents, and therefore, those prescribing DMPA use after bariatric surgery in adolescents should proceed with caution. Adult women do not have a similar response to the use of DMPA. DMPA use has rarely been associated with increased risk of venous thromboembolism (VTE). The obesity-associated increase in VTE should be mitigated by surgically induced weight loss. The concurrent use of DMPA in the post bariatric surgical period should not further increase the risk of VTE.

Hormonal contraceptives for contraception in overweight or obese women

BACKGROUND

Obesity has reached epidemic proportions around the world. Effectiveness of hormonal contraceptives may be related to metabolic changes in obesity or to greater body mass or body fat. Hormonal contraceptives include oral contraceptives (OCs), injectables, implants, hormonal intrauterine contraception (IUC), the transdermal patch, and the vaginal ring. Given the prevalence of overweight and obesity, the public health impact of any effect on contraceptive efficacy could be substantial.

OBJECTIVES

To examine the effectiveness of hormonal contraceptives in preventing pregnancy among women who are overweight or obese versus women with a lower body mass index (BMI) or weight.

SEARCH METHODS

Until 4 August 2016, we searched for studies in PubMed (MEDLINE), CENTRAL, POPLINE, Web of Science, ClinicalTrials.gov, and ICTRP. We examined reference lists of pertinent articles to identify other studies. For the initial review, we wrote to investigators to find additional published or unpublished studies.

SELECTION CRITERIA

All study designs were eligible. The study could have examined any type of hormonal contraceptive. Reports had to contain information on the specific contraceptive methods used. The primary outcome was pregnancy. Overweight or obese women must have been identified by an analysis cutoff for weight or BMI (kg/m(2)).

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data. One entered the data into RevMan and a second verified accuracy. The main comparisons were between overweight or obese women and women of lower weight or BMI. We examined the quality of evidence using the Newcastle-Ottawa Quality Assessment Scale. Where available, we included life-table rates. We also used unadjusted pregnancy rates, relative risk (RR), or rate ratio when those were the only results provided. For dichotomous variables, we computed an odds ratio with 95% confidence interval (CI).

MAIN RESULTS

With 8 studies added in this update, 17 met our inclusion criteria and had a total of 63,813 women. We focus here on 12 studies that provided high, moderate, or low quality evidence. Most did not show a higher pregnancy risk among overweight or obese women. Of five COC studies, two found BMI to be associated with pregnancy but in different directions. With an OC containing norethindrone acetate and ethinyl estradiol (EE), pregnancy risk was higher for overweight women, i.e. with BMI ≥ 25 versus those with BMI < 25 (reported relative risk 2.49, 95% CI 1.01 to 6.13). In contrast, a trial using an OC with levonorgestrel and EE reported a Pearl Index of 0 for obese women (BMI ≥ 30) versus 5.59 for nonobese women (BMI < 30). The same trial tested a transdermal patch containing levonorgestrel and EE. Within the patch group, obese women in the "treatment-compliant" subgroup had a higher reported Pearl Index than nonobese women (4.63 versus 2.15). Of five implant studies, two that examined the six-capsule levonorgestrel implant showed differences in pregnancy by weight. One study showed higher weight was associated with higher pregnancy rate in years 6 and 7 combined (reported P < 0.05). In the other, pregnancy rates differed in year 5 among the lower weight groups only (reported P < 0.01) and did not involve women weighing 70 kg or more.Analysis of data from other contraceptive methods indicated no association of pregnancy with overweight or obesity. These included depot medroxyprogesterone acetate (subcutaneous), levonorgestrel IUC, the two-rod levonorgestrel implant, and the etonogestrel implant.

AUTHORS' CONCLUSIONS

The evidence generally did not indicate an association between higher BMI or weight and effectiveness of hormonal contraceptives. However, we found few studies for most contraceptive methods. Studies using BMI, rather than weight alone, can provide information about whether body composition is related to contraceptive effectiveness. The contraceptive methods examined here are among the most effective when used according to the recommended regimen.We considered the overall quality of evidence to be low for the objectives of this review. More recent reports provided evidence of varying quality, while the quality was generally low for older studies. For many trials the quality would be higher for their original purpose rather than the non-randomized comparisons here. Investigators should consider adjusting for potential confounding related to BMI or contraceptive effectiveness. Newer studies included a greater proportion of overweight or obese women, which helps in examining effectiveness and side effects of hormonal contraceptives within those groups.

Safety and effectiveness data for emergency contraceptive pills among women with obesity: a systematic review

OBJECTIVE

This study aims to determine whether emergency contraceptive pills (ECPs) are less safe and effective for women with obesity compared with those without obesity.

STUDY DESIGN

We searched PubMed for articles through November 2015 regarding the safety and effectiveness of ECPs [ulipristal acetate (UPA), levonorgestrel (LNG) and combined estrogen and progestin] among obese users. We assessed study quality using the United States Preventive Services Task Force evidence grading system.

RESULTS

We identified four pooled secondary analyses (quality: poor to fair), two of which examined UPA and three examined LNG formulations. Three analyses pooled overlapping data from a total of three primary studies and demonstrated significant associations between obesity and risk of pregnancy after ECP use. One analysis reported a 4-fold increased risk of pregnancy among women with obesity (BMI≥30kg/m²) compared with women within normal/underweight categories (BMI<25kg/m²) after use of LNG ECPs [odds ratio (OR) 4.4; 95% confidence interval (CI) 2.0-9.4]. Further analysis of the same LNG data found that, at an approximate weight of 80 kg, the rate of pregnancy rose above 6%, which is the estimated pregnancy probability without contraception; at weights less than 75 kg, the rate of pregnancy was less than 2%. Two analyses examining UPA suggested an approximate 2-fold increased risk of pregnancy among women with obesity compared with either normal/underweight women or nonobese (BMI<30kg/m²) women (OR 2.6; 95% CI 0.9-7.0 and OR 2.1; 95% CI 1.0-4.3, respectively), but CIs were wide. Finally, the fourth secondary analysis pooled data from three separate randomized controlled trials on LNG ECPs and found no increase in pregnancy risk with increasing weight or BMI and found no consistent association between pregnancy and both factors when adjusted for other covariates.

CONCLUSION

While data are limited and poor to fair quality, findings suggest that women with obesity experience an increased risk of pregnancy after use of LNG ECP compared with those normal/underweight. Women with obesity may also experience an increased risk of pregnancy compared with women without obesity after use of UPA ECP, though differences did not reach statistical significance. Providers should counsel all women at risk for unintended pregnancy, including those with obesity, about the effectiveness of the full range of emergency contraception options in order for them to understand their options, to receive advanced supplies of emergency contraception as needed and to understand how to access an emergency copper intrauterine device if desired.

[Contraception and obesity]

The prevalence of obesity is increasing massively over several decades in industrialized countries. Obese women are sexually active but they use fewer contraceptive methods and are at high risk of unintended pregnancy. In addition, obesity is an important risk factor for venous thromboembolism events and arterial thrombosis (myocardial infarction and ischemic stroke). All of these data are to be considered in choosing a contraceptive method for obese women. Except depot medroxyprogesterone acetate injection, the progestin-only contraceptives (progestin only pills and etonogestrel subdermal implant) and the intra-uterine devices are the preferred contraceptive methods in obese women. The combined estrogen-progestin contraceptives (pill, patch and vaginal ring) may be proposed in very strict conditions (no other associated vascular risk factor). Obesity does not increase the risk of failure of most contraceptive methods. Bariatric surgery is a complex situation. It requires to program a possible pregnancy and contraception is needed for several months. Some bariatric surgical techniques such as by-pass can induce gastrointestinal malabsorption. In this situation, all oral contraceptives are not recommended because of a higher risk of failure.

Obesity and menstrual disorders

Obese women often present with oligomenorrhoea, amenorrhoea or irregular periods. The association between obesity and heavy menstrual bleeding is not well documented and data on its prevalence are limited. While the investigation protocols should be the same as for women of normal weight, particular focus is required to rule out endometrial hyperplasia in obese women. The treatment modalities of menstrual disorders for obese women will be, in principle, similar to those of normal weight. However, therapeutic outcomes in terms of effectiveness and adverse outcomes need special consideration when dealing with women with a high body mass index (BMI). Here, different treatment strategies are reviewed paying particular attention to the effect of weight on their efficacy and the challenges of providing each treatment option. This chapter aims to review the current literature and address areas where further evidence is needed, which will subsequently influence clinical practice.

Contraception and sexual health in obese women

As the proportion of women with obesity increases worldwide, understanding the influence of body weight on sexual behavior, fertility, and contraceptive effectiveness is critical for health-care professionals and patients. Although many have theorized that obese women are different from normal-weight women regarding sexual health and behavior, current evidence for the most part disproves this. The exception is in adolescents where body image may play a role in riskier behavior, placing them at a greater risk of an unintended pregnancy. Given that most modern contraceptives were not originally evaluated in obese women, understanding how weight affects contraceptive pharmacokinetics and efficacy should be a focus of ongoing research. Evidence is reassuring that most modern contraceptive methods are safe and effective in obese women. This paper reviews what is known about sexual and contraceptive behavior, as well as the effectiveness and pharmacokinetics of modern contraceptives, for overweight and obese women.

Effectiveness of oral contraceptive pills in a large U.S. cohort comparing progestogen and regimen

OBJECTIVE

To estimate real-life effectiveness of oral contraceptive pills by progestogen, length of pill-free interval, and body mass index while focusing on the effect of progestogens with a long half-life and on 24-day oral contraceptive pills regimens.

METHODS

Outcome data from 52,218 U.S. participants in the International Active Surveillance of Women Taking Oral Contraceptives—a large, prospective, controlled, noninterventional, long-term cohort study with active surveillance of the study participants—were used to analyze contraceptive failure in association with oral contraceptive pills use. Low loss to follow-up is ensured by a comprehensive follow-up procedure. Contraceptive failure rates are described by Pearl Index and life-table analysis. Inferential statistics for contraceptive failure are based on Cox regression models.

RESULTS

Analyses are based on 1,634 unintended pregnancies during 73,269 woman-years of oral contraceptive pills exposure. Life-table estimates of contraceptive failure for a 24-day regimen of drospirenone and ethinyl estradiol and 21-day regimens of other progestogens were 2.1% and 3.5% after the first study year, and 4.7% and 6.7% after the third year. The adjusted hazard ratio was 0.7 (95% confidence interval 0.6–0.8). Direct comparisons of the 24-day and 21-day regimens of drospirenone and norethisterone, respectively, showed also lower contraceptive failure rates for 24-day regimens. Contraceptive failure rates adjusted for age, parity and educational level showed a slight increase with higher body mass index.

CONCLUSION

The 24-day oral contraceptive regimens containing a progestogen with a long half-life show higher contraceptive effectiveness under routine medical conditions compared with conventional 21-day regimens. Obesity seems to be associated with a slight reduction of contraceptive effectiveness.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, www.clinicaltrials.gov, NCT00335257.

LEVEL OF EVIDENCE

II

Impact of body mass index on suppression of follicular development and ovulation using a transdermal patch containing 0.55-mg ethinyl estradiol/2.1-mg gestodene: a multicenter, open-label, uncontrolled study over three treatment cycles

BACKGROUND

Body mass index (BMI) may influence ovulation inhibition resulting from transdermal hormone delivery. Investigation of this effect is important given the high prevalence of obesity in the US.

STUDY DESIGN

This open-label, uncontrolled, Phase 2b trial stratified 173 women (18-35 years) according to three BMI groups (Group 1, n = 56, ≤ 30 kg/m²; Group 2, n = 55, > 30 kg/m² and ≤ 35 kg/m²; and Group 3, n = 47, > 35 kg/m²). Women used a contraceptive patch containing 0.55-mg ethinyl estradiol (EE) and 2.1-mg gestodene (GSD). The EE/GSD patch was used weekly for three 28-day cycles (one patch per week for 3 consecutive weeks followed by a 7-day, patch-free interval), and its effect on ovulation was assessed by the Hoogland score, a composite score that comprises transvaginal ultrasound and estradiol (E₂) and progesterone levels every 3 days in Cycles 2 and 3. Evaluation of pharmacokinetic parameters was a secondary aim of the study, and blood samples for analytic determination of EE, GSD and sex hormone-binding globulin were taken during the pretreatment cycle, Cycle 2 and Cycle 3. Compliance was assessed using diary information and serum drug levels.

RESULTS

In the per-protocol set, there were only six ovulations during the study, and no participant ovulated in both study cycles. One ovulation occurred in Group 1, three in Group 2 and two in Group 3. Ovulation inhibition was unaffected by BMI; in all groups, most participants had Hoogland scores of 1 or 2 (i.e., follicle-like structures < 13 mm: Group 1, ≤ 30 kg/m², 80.0% in Cycle 2, 85.7% in Cycle 3; Group 2, > 30 kg/m² and ≤ 35 kg/m², 61.4% in Cycle 2, 75.0% in Cycle 3; Group 3, > 35 kg/m², 78.0% in Cycle 2, 72.5% in Cycle 3). Serum levels of follicle-stimulating hormone, luteinizing hormone, E2 and progesterone were similar between groups. Body weight had a limited effect on EE clearance that was unlikely to be clinically relevant.

CONCLUSION

The EE/GSD patch provided effective ovulation inhibition, even in women with higher BMI.

IMPLICATIONS

This is the largest-to-date study of physiologic endpoints and found no clinically important differences in ovarian suppression among obese and normal-weight users of the EE/GSD contraceptive patch, thus providing reassurance that obese women can achieve the same high level of contraceptive protection as normal-weight users.

Steroidal contraceptives: effect on carbohydrate metabolism in women without diabetes mellitus

BACKGROUND

Many hormonal contraceptives have been associated with changes in carbohydrate metabolism. Alterations may include decreased glucose tolerance and increased insulin resistance, which are risk factors for Type 2 diabetes mellitus and cardiovascular disease. These issues have been raised primarily with contraceptives containing estrogen.

OBJECTIVES

To evaluate the effect of hormonal contraceptives on carbohydrate metabolism in healthy women and those at risk for diabetes due to overweight.

SEARCH METHODS

In April 2014, we searched the computerized databases MEDLINE, POPLINE, CENTRAL, and LILACS for studies of hormonal contraceptives and carbohydrate metabolism. We also searched for clinical trials in ClinicalTrials.gov and ICTRP. The initial search also included EMBASE.

SELECTION CRITERIA

All randomized controlled trials were considered if they examined carbohydrate metabolism in women without diabetes who used hormonal contraceptives for contraception. Comparisons could be a placebo, a non-hormonal contraceptive, or another hormonal contraceptive that differed in drug, dosage, or regimen. Interventions included at least three cycles. Outcomes included glucose and insulin measures.

DATA COLLECTION AND ANALYSIS

We assessed all titles and abstracts identified during the literature searches. The data were extracted and entered into RevMan. We wrote to researchers for missing data. For continuous variables, the mean difference (MD) was computed with 95% confidence interval (CI) using a fixed-effect model. For dichotomous outcomes, the Peto odds ratio with 95% CI was calculated.

MAIN RESULTS

We found 31 trials that met the inclusion criteria. No new trials were eligible in 2014. Twenty-one trials compared combined oral contraceptives (COCs); others examined different COC regimens, progestin-only pills, injectables, a vaginal ring, and implants. None included a placebo. Of 34 comparisons, eight had any notable difference between the study groups in an outcome.Twelve trials studied desogestrel-containing COCs, and the few differences from levonorgestrel COCs were inconsistent. A meta-analysis of two studies showed the desogestrel group had a higher mean fasting glucose (MD 0.20; 95% CI 0.00 to 0.41). Where data could not be combined, single studies showed lower mean fasting glucose (MD -0.40; 95% CI -0.72 to -0.08) and higher means for two-hour glucose response (MD 1.08; 95% CI 0.45 to 1.71) and insulin area under the curve (AUC) (MD 20.30; 95% CI 4.24 to 36.36).Three trials examined the etonogestrel vaginal ring and one examined an etonogestrel implant. One trial showed the ring group had lower mean AUC insulin than the levonorgestrel-COC group (MD -204.51; 95% CI -389.64 to -19.38).Of eight trials of norethisterone preparations, five compared COCs and three compared injectables. In a COC trial, a norethisterone group had smaller mean change in glucose two-hour response than a levonorgestrel-COC group (MD -0.30; 95% CI -0.54 to -0.06). In an injectable study, a group using depot medroxyprogesterone acetate had higher means than the group using norethisterone enanthate for fasting glucose (MD 10.05; 95% CI 3.16 to 16.94), glucose two-hour response (MD 17.00; 95% CI 5.67 to 28.33), and fasting insulin (MD 3.40; 95% CI 2.07 to 4.73).Among five recent trials, two examined newer COCs with different estrogen types. One showed the group with nomegestrel acetate plus 17β-estradiol had lower means than the levonorgestrel group for incremental AUC glucose (MD -1.43; 95% CI -2.55 to -0.31) and glycosylated hemoglobin (HbA1c) (MD -0.10; 95% CI -0.18 to -0.02). Two trials compared extended versus conventional (cyclic) regimens. With a dienogest COC, an extended-use group had greater mean change in AUC glucose (MD 82.00; 95% CI 10.72 to 153.28). In a small trial using two levonorgestrel COCs, the lower-dose group showed smaller mean change in fasting glucose (MD -3.00; 95% CI -5.89 to -0.11), but the obese and normal weight women did not differ significantly.

AUTHORS' CONCLUSIONS

Current evidence suggests no major differences in carbohydrate metabolism between different hormonal contraceptives in women without diabetes. We cannot make strong statements due to having few studies that compared the same types of contraceptives. Many trials had small numbers of participants and some had large losses. Many of the earlier studies had limited reporting of methods.We still know very little about women at risk for metabolic problems due to being overweight. More than half of the trials had weight restrictions as inclusion criteria. Only one small trial stratified the groups by body mass index (obese versus normal).

Progestin-only contraceptives: effects on weight

BACKGROUND

Progestin-only contraceptives (POCs) are appropriate for many women who cannot or should not take estrogen. Many POCs are long-acting, cost-effective methods of preventing pregnancy. However, concern about weight gain can deter the initiation of contraceptives and cause early discontinuation among users.

OBJECTIVES

The primary objective was to evaluate the association between progestin-only contraceptive use and changes in body weight.

SEARCH METHODS

Through May 2013, we searched MEDLINE, CENTRAL, POPLINE, LILACS, ClinicalTrials.gov, and ICTRP. The 2010 search also included EMBASE. For the initial review, we contacted investigators to identify other trials.

SELECTION CRITERIA

All comparative studies were eligible that examined a POC versus another contraceptive method or no contraceptive. The primary outcome was mean change in body weight or mean change in body composition. We also considered the dichotomous outcome of loss or gain of a specified amount of weight.

DATA COLLECTION AND ANALYSIS

Two authors extracted the data. We computed the mean difference (MD) with 95% confidence interval (CI) for continuous variables. For dichotomous outcomes, the Mantel-Haenszel odds ratio (OR) with 95% CI was calculated.

MAIN RESULTS

We found 16 studies; one examined progestin-only pills, one studied the levonorgestrel-releasing intrauterine system (LNG-IUS), four examined an implant, and 10 focused on depot medroxyprogesterone acetate (DMPA). Outcomes examined were changes in body weight only (14 studies), changes in both body weight and body composition (1 study), and changes in body composition only (1 study). We did not conduct meta-analysis due to the various contraceptive methods and weight change measures.Comparison groups did not differ significantly for weight change in 12 studies. However, three studies showed weight change differences for POC users compared to women not using a hormonal method. In one study, weight gain (kg) was greater for the DMPA group than the group using a non-hormonal IUD in years one through three [(MD 2.28; 95% CI 1.79 to 2.77), (MD 2.71, 95% CI 2.12 to 3.30), and (MD 3.17; 95% CI 2.51 to 3.83), respectively]. The differences were notable within the normal weight and overweight subgroups. Two implant studies also showed differences in weight change. The implant group (six-capsule) had greater weight gain (kg) compared to the group using a non-hormonal IUD in both studies [(MD 0.47 (95% CI 0.29 to 0.65); (MD 1.10; 95% CI 0.36 to 1.84)]. In one of those studies, the implant group also had greater weight gain than a group using a barrier method or no contraceptive (MD 0.74; 95% CI 0.52 to 0.96).The two studies that assessed body composition change showed differences between POC users and women not using a hormonal method. Adolescents using DMPA had a greater increase in body fat (%) compared to a group not using a hormonal method (MD 11.00; 95% CI 2.64 to 19.36). The DMPA group also had a greater decrease in lean body mass (%) (MD -4.00; 95% CI -6.93 to -1.07). The other study reported differences between an LNG-IUS group and a non-hormonal IUD group in percent change in body fat mass (2.5% versus -1.3%, respectively; reported P value = 0.029) and percent change in lean body mass (-1.4% versus 1.0%, respectively; reported P value = 0.027).

AUTHORS' CONCLUSIONS

The overall quality of evidence was moderate to low, given that the studies were evenly divided across the evidence quality groups (high, moderate, low, or very low quality). We found limited evidence of weight gain when using POCs. Mean gain was less than 2 kg for most studies up to 12 months. Weight change for the POC group generally did not differ significantly from that of the comparison group using another contraceptive. Two studies that assessed body composition showed that POC users had greater increases in body fat and decreases in lean body mass compared to users of non-hormonal methods. Appropriate counseling about typical weight gain may help reduce discontinuation of contraceptives due to perceptions of weight gain.

Contraception and the obese woman

PURPOSE

Obesity has reached epidemic rates among U.S. women of reproductive age, many of whom want to use contraception. However, some forms of contraception can have adverse effects on an obese woman's health. This article explores risks of contraception available in the United States and provides clinical recommendations for use by obese women.

DATA SOURCES

Information was compiled by reviewing the scientific literature on contraception and female obesity using CINAHL, MEDLINE, PubMed search engines.

CONCLUSIONS

The evidence is largely supportive of combined oral contraceptive (COC) use in carefully screened obese women without known risks factors for cardiovascular disease. The efficacy of COCs may be slightly reduced in obese women because of increased body mass. Other types of hormonal contraceptives have varying safety and efficacy reports when used by obese women. Intrauterine devices do not have reduced efficacy nor increased risks for obese women but insertion may be more difficult. Obesity has no effect on efficacy of barrier methods of contraception.

IMPLICATIONS

Clinicians should conduct a careful history and physical exam with selected supporting laboratory tests when considering prescription of hormonal contraceptives for obese women. Obese women require health counseling to carefully follow directions for contraceptive use to avoid unintended pregnancy.

Hormonal contraceptives for contraception in overweight or obese women

BACKGROUND

Obesity has reached epidemic proportions around the world. Effectiveness of hormonal contraceptives may be related to metabolic changes in obesity or greater body mass or body fat. Hormonal contraceptives mainly include oral contraceptives, injectables and implants, the transdermal patch, and the vaginal ring. We systematically reviewed the evidence on the effectiveness of hormonal contraceptives among overweight and obese women.

OBJECTIVES

To examine the effectiveness of hormonal contraceptives in preventing unplanned pregnancies among women who are overweight or obese versus women of lower weight or body mass index (BMI).

SEARCH METHODS

Through January 2013, we searched MEDLINE, CENTRAL, POPLINE, ClinicalTrials.gov, and ICTRP. The previous search also included EMBASE. We contacted investigators to identify other trials.

SELECTION CRITERIA

All study designs were eligible. Any type of hormonal contraceptive could have been examined. Reports had to contain information on the specific contraceptive method(s). The primary outcome was pregnancy. Overweight or obese women must have been identified by an analysis cutoff for weight or BMI (kg/m(2)).

DATA COLLECTION AND ANALYSIS

Data were abstracted by two authors. Life-table rates were included where available. For dichotomous variables, we computed an odds ratio with 95% confidence interval (CI). We used reported pregnancy rates or relative risk (RR) when those were the only results provided. The main comparisons were between overweight or obese women and women of lower weight or BMI. We assessed the quality of evidence for this review.

MAIN RESULTS

We found nine reports with data from 13 trials that included a total of 49,712 women. Five reports from 2002 to 2012 compared BMI groups; of those, one reported a higher pregnancy risk for overweight or obese women. In that trial, women assigned to an oral contraceptive containing norethindrone acetate 1.0 mg plus EE 20 µg and having a BMI at least 25 had greater pregnancy risk compared to those with BMI less than 25 (reported RR 2.49; 95% CI 1.01 to 6.13). The comparisons reported in the other four studies were not significantly different for pregnancy. These included studies of a combined oral contraceptive (COC), a transdermal patch, an implant, and an injectable. The COC study showed no trend by BMI or weight. With the transdermal patch, body weight was associated with pregnancy (reported P < 0.001) but BMI was not. The implant study had one pregnancy and the injectable study reported no pregnancies.Four studies from the 1990s used weight alone rather than BMI. Results were mixed. Studies of a vaginal ring (never marketed) and a six-rod implant showed higher pregnancy rates for women weighing at least 70 kg versus those weighing less than 70 kg (reported P values: 0.0013 and < 0.05, respectively). However, two implant studies showed no trend by body weight.

AUTHORS' CONCLUSIONS

The evidence did not generally show an association of BMI with effectiveness of hormonal contraceptives. However, the evidence was limited for any individual contraceptive method. Studies using BMI (rather than weight alone) can provide more information about whether body composition is related to contraceptive effectiveness. The efficacy of subdermal implants and injectable contraceptives may be unaffected by body mass. The contraceptive methods examined here are among the most effective when the recommended regimen is followed.The overall quality of evidence was low for this review. More recent reports provided moderate quality evidence, while the older studies provided evidence of low or very low quality for our purposes. Investigators should consider adjusting for potential confounding related to BMI. Trials should be designed to include sufficient numbers of overweight or obese women to adequately examine effectiveness and side effects of hormonal contraceptives within those groups.

The creeping Pearl: Why has the rate of contraceptive failure increased in clinical trials of combined hormonal contraceptive pills?

BACKGROUND

Despite several drawbacks, the Pearl Index continues to be the most widely used statistical measure of contraceptive failure. However, Pearl indices reported in studies of newer hormonal contraceptives appear to be increasing.

STUDY DESIGN

We searched PubMed and Medical Intelligence Solutions databases for prospective trials evaluating oral contraceptive (OC) efficacy to examine potential factors that could contribute to increasing Pearl indices.

RESULTS

Numerous potential factors were identified, including an increased rate of failures of newer OCs, deficiencies in methods of calculating contraceptive failure rates, differences in study design and changes in patient populations resulting in increased rates of contraceptive failures due to the inappropriate or inconsistent use of the method.

CONCLUSIONS

The two most likely important contributors to the increase in Pearl indices are more frequent pregnancy testing with more sensitive tests and less adherent study populations. Because study populations appear to be increasingly representative of the likely actual users once the product is marketed, we can expect to see even higher failure rates in ongoing and future studies. This result poses challenges for companies and regulatory agencies.

Contraceptive failures in overweight and obese combined hormonal contraceptive users

OBJECTIVE

To estimate weather contraceptive failure rates among combined oral contraceptive pill (OCP), patch, and vaginal ring users was associated with increasing body mass index (BMI).

METHODS

Females enrolled in a large contraceptive study offering the reversible method of their choice at no cost were followed-up for 2-3 years. We compared the failure rates (pregnancy) among users of the OCP, transdermal patch, and contraceptive vaginal ring stratified by BMI.

RESULTS

Among the 7,486 participants available for this analysis, 1,523 chose OCPs, patch, or ring at enrollment. Of the 334 unintended pregnancies, 128 were found to be a result of OCP, patch, or ring failure. Three-year failure rates were not different across BMI categories (BMI less than 25 8.44%, 95% confidence interval [CI] 6.1-11.5; BMI 25-30 11.03%, 95% CI 7.5-16.0; BMI more than 30 8.92%, 95% confidence interval 7.6-11.5). Increasing parity (hazard ratio [HR] 3.06, CI 1.31-7.18) and history of a previous unintended pregnancy (HR 2.82, CI 1.63-4.87), but not BMI, were significant risk factors for unintended pregnancy.

CONCLUSION

Overweight and obese females do not appear to be at increased risk for contraceptive failure when using the OCP, patch, or vaginal ring.

Diabetes and oral contraception

The prevalence of diabetes mellitus is increasing dramatically worldwide, resulting in more and more women of reproductive age being affected by either type 1 or type 2 diabetes. Management of contraception is a major issue due to the specific risks associated with pregnancy and those potentially induced by hormonal contraceptives in diabetic women. This review emphasizes the urgent need to improve the use of contraception in women with diabetes. There is no consistent evidence that combined oral contraceptives significantly influence the risk of developing diabetes, even in women with a history of gestational diabetes. Furthermore, although data from specific studies remain sparse, no worsening effect has been reported in diabetic women, either in glycemic control or on the course of microvascular complications. Thus, the use of estroprogestive pills is now recognized as a safe and effective option for preconception care of women with uncomplicated diabetes. According to recent guidelines, these contraceptives must be avoided in case of associated cardiovascular risk factors, cardiovascular disease or severe microvascular complications such as nephropathy with proteinuria or active proliferative retinopathy. Prescription of combined hormonal contraception in type 2 diabetic women must also be considered with caution due to a frequent association with obesity and vascular risk factors which increase both thromboembolic and arterial risks. Thanks to their metabolic and vascular safety profile, progestin-only contraceptives, as well as non-hormonal methods, represent alternatives according to patient wishes.

Maternal obesity and pre-pregnancy folic acid supplementation

OBJECTIVE

The purpose of this nested cohort study was to compare the rate of pre-pregnancy supplementation in obese women with that of women with a normal BMI.

METHODS

Pregnant women were enrolled at their convenience in a large university hospital. Weight and height were measured in the first trimester and BMI categorised.

RESULTS

Of the 288 women, 35.1% were in the normal, 29.5% in the overweight and 35.4% in the obese BMI categories. Only 45.1% (n = 46) of the obese women took pre-pregnancy folic acid compared with 60.4% (n = 61) of women with a normal BMI (p < 0.03). The lower incidence of folic acid supplementation in obese women was associated with an unplanned pregnancy in 36.3% of women compared with 22.8% in the normal BMI category (p < 0.04).

CONCLUSIONS

Obese women should take folate supplements whether they are planning to conceive or not.

Effect of the ethinylestradiol/levonorgestrel combined oral contraceptive on the activity of cytochrome P4503A in obese women

AIM(S)

While it is known that CYP3A4/5 activity is decreased with combined oral contraceptive (COC) use and obesity suppresses CYP expression, the combined effects of obesity and COC use on CYP3A4/5 activity are unclear. Therefore, our aim was to examine the effect of COC usage on CYP3A4/5 activity in obese women.

METHODS

Thirty-four, obese (body mass index, BMI > 30 kg m(-2)) women of reproductive age (18-35 years old) were placed on a COC pill containing 20 µg ethinylestradiol/100 µg levonorgestrel for 21 days starting at the onset of menses. A midazolam pharmacokinetic study was conducted prior to initiation and after 21 days of COC treatment. Serial blood samples were collected and plasma concentrations of midazolam were measured using liquid chromatography tandem mass spectrometry. Pharmacokinetic parameters were estimated using a non-compartmental method.

RESULTS

Midazolam clearance, a surrogate measure of CYP3A4/5 activity, was significantly decreased upon COC use (63.3 l h(-1) vs. 53.9 l h(-1), P < 0.05). A median decrease of 5.6 l h(-1) (95% CI -4.1, 13.3 l h(-1)) was observed. However, the magnitude of change was similar to that reported in women with normal BMI.

CONCLUSIONS

Although we hypothesized that obesity might amplify the impact on CYP3A4/5 activity in COC users, we found that this was not the case. This finding is reassuring regarding potential additional drug-drug interactions in obese COC users as CYP3A4/5 is a major enzyme in the metabolism of many marketed drugs.

Steroidal contraceptives: effect on carbohydrate metabolism in women without diabetes mellitus

BACKGROUND

Many hormonal contraceptives have been associated with changes in carbohydrate metabolism. Alterations may include decreased glucose tolerance and increased insulin resistance, which are risk factors for Type 2 diabetes mellitus and cardiovascular disease. These issues have been raised primarily with contraceptives containing estrogen.

OBJECTIVES

To evaluate the effect of hormonal contraceptives on carbohydrate metabolism in healthy women and those at risk for diabetes due to overweight.

SEARCH METHODS

In February 2012, we searched the computerized databases MEDLINE, POPLINE, CENTRAL, and LILACS for studies of hormonal contraceptives and carbohydrate metabolism. We also searched for clinical trials in ClinicalTrials.gov and ICTRP. Previous searches also included EMBASE.

SELECTION CRITERIA

All randomized controlled trials were considered if they examined carbohydrate metabolism in women without diabetes who used hormonal contraceptives for contraception. Comparisons could be a placebo, a non-hormonal contraceptive, or another hormonal contraceptive that differed in drug, dosage, or regimen. Interventions included at least three cycles. Outcomes included glucose and insulin measures.

DATA COLLECTION AND ANALYSIS

We assessed all titles and abstracts identified during the literature searches. The data were extracted and entered into RevMan. We wrote to researchers for missing data. For continuous variables, the mean difference (MD) was computed with 95% confidence interval (CI) using a fixed-effect model. For dichotomous outcomes, the Peto odds ratio with 95% CI was calculated.

MAIN RESULTS

We found 31 trials that met the inclusion criteria. Twenty-one trials compared combined oral contraceptives (COCs); others examined different COC regimens, progestin-only pills, injectables, a vaginal ring, and implants. None included a placebo. Of 34 comparisons, eight had any notable difference between the study groups in an outcome.Twelve trials studied desogestrel-containing COCs, and the few differences from levonorgestrel COCs were inconsistent. A meta-analysis of two studies showed the desogestrel group had a higher mean fasting glucose (MD 0.20; 95% CI 0.00 to 0.41). Where data could not be combined, single studies showed lower mean fasting glucose (MD -0.40; 95% CI -0.72 to -0.08) and higher means for two-hour glucose response (MD 1.08; 95% CI 0.45 to 1.71) and insulin area under the curve (AUC) (MD 20.30; 95% CI 4.24 to 36.36).Three trials examined the etonogestrel vaginal ring and one examined an etonogestrel implant. One trial showed the ring group had lower mean AUC insulin than the levonorgestrel-COC group (MD -204.51; 95% CI -389.64 to -19.38).Of eight trials of norethisterone preparations, five compared COCs and three compared injectables. In a COC trial, a norethisterone group had smaller mean change in glucose two-hour response than a levonorgestrel-COC group (MD -0.30; 95% CI -0.54 to -0.06). In an injectable study, a group using depot medroxyprogesterone acetate had higher means than the group using norethisterone enanthate for fasting glucose (MD 10.05; 95% CI 3.16 to 16.94), glucose two-hour response (MD 17.00; 95% CI 5.67 to 28.33), and fasting insulin (MD 3.40; 95% CI 2.07 to 4.73).Among five recent trials, two examined newer COCs with different estrogen types. One showed the group with nomegestrel acetate plus 17β-estradiol had lower means than the levonorgestrel group for incremental AUC glucose (MD -1.43; 95% CI -2.55 to -0.31) and glycosylated hemoglobin (HbA1c) (MD -0.10; 95% CI -0.18 to -0.02). Two trials compared extended versus conventional (cyclic) regimens. With a dienogest COC, an extended-use group had greater mean change in AUC glucose (MD 82.00; 95% CI 10.72 to 153.28). In a small trial using two levonorgestrel COCs, the lower-dose group showed smaller mean change in fasting glucose (MD -3.00; 95% CI -5.89 to -0.11), but the obese and normal weight women did not differ significantly.

AUTHORS' CONCLUSIONS

Current evidence suggests no major differences in carbohydrate metabolism between different hormonal contraceptives in women without diabetes. We cannot make strong statements due to having few studies that compared the same types of contraceptives. Many trials had small numbers of participants and some had large losses. Many of the earlier studies had limited reporting of methods.We still know very little about women at risk for metabolic problems due to being overweight. More than half of the trials had weight restrictions as inclusion criteria. Only one small trial stratified the groups by body mass index (obese versus normal).

Contraception in obese older women

Obesity is increasing in most western countries and rises significantly with age. Obese women are as sexually active as women of normal weight, and new sexual relationships in the older reproductive years are becoming more commonplace and still require effective contraception. Continuation of pregnancy in a woman over 40 carries health risks which are exacerbated by the presence of obesity. A high proportion of pregnancies in women over 40 are unplanned and end in therapeutic abortion. The prevalence of obesity and the high rates of contraceptive use amongst older women mean that any increase in associated risk is likely to be of public health concern. There are very few data on the specific risks of contraceptive use in obese older women. As fertility declines with age, all methods become increasingly effective. No single method is contraindicated by age alone but particular caution is required where the use of estrogen containing preparations is considered as the risks associated with estrogen are all also independently associated with increasing age and body mass index. Non-estrogen containing methods are available, whether hormonal, barrier or surgical, which are effective, acceptable and safer in the obese older woman. Some methods of contraception may indeed have particular non-contraceptive benefits for this population.

Body weight does not impact pregnancy rates during use of a low-dose extended-regimen 91-day oral contraceptive

BACKGROUND

This study evaluated the impact of weight on efficacy during use of an extended oral contraceptive (OC).

STUDY DESIGN

Data were from a Phase 3 clinical trial evaluating the efficacy of a low-dose 91-day extended regimen of 100 mcg levonorgestrel/20 mcg ethinyl estradiol (LNG/EE; 84 days)+10 mcg EE (7 days) for the prevention of pregnancy. Crude pregnancy rates were calculated for weight and body mass index (BMI) deciles.

RESULTS

Of the 1736 women in this analysis, 878 (50.6%) had a BMI greater than 25 kg/m2, and 770 (44.4%) were heavier than 70 kg. Pregnancies occurred in 36 women. Crude pregnancy rates were similar across weight and BMI deciles, with no discernable differences observed between deciles using either classification criterion.

CONCLUSIONS

No evidence of any reduction in the level of contraceptive efficacy was observed with this low-dose extended OC regimen in overweight and obese women.

Implications of obesity for drug therapy: limitations and challenges

Obesity has become a worldwide challenge with significant health and socioeconomic implications. One of the major implications is its impact on drug therapy. In order to gain a better understanding of this impact, we surveyed the regulatory guidances, the newly approved molecular entity drug products, and drug product labels in the Physician's Desk Reference. This review summarizes the findings of the survey along with the existing knowledge on pharmacokinetic and pharmacodynamic changes associated with obesity.

Putting risk into perspective: the US medical eligibility criteria for contraceptive use

Unintended pregnancy remains a considerable problem in the United States, with health risks for both mother and infant. These risks may be increased among women with medical conditions, for whom pregnancy can lead to severe adverse outcomes. Highly effective and safe contraceptive methods are available to prevent unintended pregnancy. However, women with medical conditions and their providers also may be concerned about potential risks associated with contraceptive method use. Evidence-based guidance documents can be helpful tools for clinicians to efficiently use evidence and put risks into perspective. The US Medical Eligibility Criteria for Contraceptive Use, 2010, provides evidence-based recommendations for the safety of contraceptive use among women with medical conditions and other characteristics. While some contraceptive methods pose risks for some women, these must be considered in context and weighed against such considerations as the absolute risk of adverse events and the risks associated with pregnancy. Most women, even women with medical conditions, can safely use highly effective methods of contraception and promoting their use will further efforts to reduce unintended pregnancy.

Progestin-only contraceptives: effects on weight

BACKGROUND

Progestin-only contraceptives (POCs) are appropriate for many women who cannot or should not take estrogen. Many POCs are long-acting, cost-effective methods of preventing pregnancy. However, concern about weight gain can deter the initiation of contraceptives and cause early discontinuation among users.

OBJECTIVES

The primary objective was to evaluate the association between progestin-only contraceptive use and changes in body weight.

SEARCH STRATEGY

We searched MEDLINE, CENTRAL, POPLINE, EMBASE, LILACS, ClinicalTrials.gov, and ICTRP, and contacted investigators to identify other trials.

SELECTION CRITERIA

All comparative studies were eligible that examined a POC versus another method or no contraceptive. The primary outcome was mean change in body weight or body composition.

DATA COLLECTION AND ANALYSIS

Two authors extracted the data. We computed the mean difference with 95% confidence interval (CI) for continuous variables and odds ratio with 95% CI for dichotomous variables.

MAIN RESULTS

We did not conduct meta-analysis due to the various contraceptive methods and weight change measures. Fifteen studies examined progestin-only pills (N=1), Norplant (N=4), and depot medroxyprogesterone acetate (DMPA) (N=10). Comparison groups were similar for weight change in 11 studies. Four studies showed differences in weight or body composition change for POCs compared to no hormonal method. Adolescents using DMPA had a greater increase in body fat (%) versus a group using no hormonal method (mean difference 11.00; 95% CI 2.64 to 19.36). The DMPA group also had a greater decrease in lean body mass (%) (mean difference -4.00; 95% CI -6.93 to -1.07). In another study, weight gain (kg) was greater for the DMPA group than an IUD group (mean difference 2.28, 2.71, 3.17, respectively). The differences were notable within the normal weight and overweight subgroups. One study showed the Norplant (six-capsule) group had greater weight gain (kg) than a non-hormonal IUD group (mean difference 0.47 (95% CI 0.29 to 0.65) and a group using non-hormonal or no method (mean difference 0.74; 95% CI 0.52 to 0.96). Another study also showed a Norplant group also had greater weight gain (kg) than an IUD group (mean difference 1.10; 95% CI 0.36 to 1.84).

AUTHORS' CONCLUSIONS

We found little evidence of weight gain when using POCs. Mean gain was less than 2 kg for most studies up to 12 months, and usually similar for the comparison group using another contraceptive. Appropriate counseling about typical weight gain may help reduce discontinuation of contraceptives due to perceptions of weight gain.

Can we identify women at risk of pregnancy despite using emergency contraception? Data from randomized trials of ulipristal acetate and levonorgestrel

BACKGROUND

Emergency contraception (EC) does not always work. Clinicians should be aware of potential risk factors for EC failure.

STUDY DESIGN

Data from a meta-analysis of two randomized controlled trials comparing the efficacy of ulipristal acetate (UPA) with levonorgestrel were analyzed to identify factors associated with EC failure.

RESULTS

The risk of pregnancy was more than threefold greater for obese women compared with women with normal body mass index (odds ratio (OR), 3.60; 95% confidence interval (CI), 1.96-6.53; p<.0001), whichever EC was taken. However, for obese women, the risk was greater for those taking levonorgestrel (OR, 4.41; 95% CI, 2.05-9.44, p=.0002) than for UPA users (OR, 2.62; 95% CI, 0.89-7.00; ns). For both ECs, pregnancy risk was related to the cycle day of intercourse. Women who had intercourse the day before estimated day of ovulation had a fourfold increased risk of pregnancy (OR, 4.42; 95% CI, 2.33-8.20; p<.0001) compared with women having sex outside the fertile window. For both methods, women who had unprotected intercourse after using EC were more likely to get pregnant than those who did not (OR, 4.64; 95% CI, 2.22-8.96; p=.0002).

CONCLUSIONS

Women who have intercourse around ovulation should ideally be offered a copper intrauterine device. Women with body mass index >25 kg/m(2) should be offered an intrauterine device or UPA. All women should be advised to start effective contraception immediately after EC.

Hormonal contraceptives for contraception in overweight or obese women

BACKGROUND

Obesity has reached epidemic proportions around the world. Metabolic changes in obesity and greater body mass may lead to reduced effectiveness of hormonal contraceptives, such as the skin patch, vaginal ring, implants, and injectables. We systematically reviewed the evidence on the effectiveness of hormonal contraceptives among overweight and obese women.

OBJECTIVES

To examine the effectiveness of hormonal contraceptives in preventing unplanned pregnancies among women who are overweight or obese versus women of lower weight or body mass index (BMI).

SEARCH STRATEGY

We searched MEDLINE, CENTRAL, POPLINE, EMBASE, ClinicalTrials.gov, and ICTRP. We also contacted investigators to identify other trials.

SELECTION CRITERIA

All study designs were eligible. Any type of hormonal contraceptive could have been examined. The primary outcome was pregnancy. Overweight or obese women must have been identified by an analysis cutoff for weight or BMI (kg/m(2)).

DATA COLLECTION AND ANALYSIS

Data were abstracted by two authors; life-table rates were included where available. For dichotomous variables, we computed an odds ratio with 95% confidence interval. The main comparisons were between overweight or obese women and women of lower weight or BMI.

MAIN RESULTS

We found 7 reports with data from 11 trials that included 39,531 women. One of three studies using BMI found a higher pregnancy risk for overweight or obese women. In the trial of two combination oral contraceptives, women with BMI >= 25 had greater pregnancy risk compared to those with BMI < 25 (OR 1.91; 95% CI 1.01 to 3.61). Among skin patch users, body weight was associated with pregnancy (reported P < 0.001) but BMI was not. Studies of a vaginal ring (never marketed) and a six-rod implant showed higher pregnancy rates for women weighing >= 70 kg versus those weighing < 70 kg (reported P values: 0.0013 and < 0.05, respectively). However, two implant studies showed no trend by body weight, and trials of an injectable had no pregnancies.

AUTHORS' CONCLUSIONS

Body weight addresses overall body size, while BMI generally reflects the amount of fat. Only one of three studies using BMI found a higher pregnancy risk for overweight women. The efficacy of implants and injectable contraceptives may be unaffected by body mass. The field could use trials of contraceptive methods with groups stratified by BMI. The current evidence on effectiveness by BMI is limited. However, the contraceptive methods examined here are still among the most effective when the recommended regimen is followed.

Sexuality and obesity, a gender perspective: results from French national random probability survey of sexual behaviours

OBJECTIVES

To analyse the association between body mass index (BMI) and sexual activity, sexual satisfaction, unintended pregnancies, and abortions in obese people and to discuss the implications for public health practices, taking into account the respondents' and their partners' BMI.

DESIGN

Random probability survey of sexual behaviours.

SETTING

National population based survey of 12 364 men and women aged 18-69 living in France in 2006.

PARTICIPANTS

Random selection of 5535 women and 4635 men, of whom 3651 women and 2725 men were normal weight (BMI 18.5-<25), 1010 women and 1488 men were overweight (BMI 25-<30), and 411 women and 350 men were obese (BMI >30).

RESULTS

Obese women were less likely than normal weight women to report having a sexual partner in the past 12 months (odds ratio 0.71, 95% confidence interval 0.51 to 0.97). Obese men were less likely than normal weight men to report more than one sexual partner in the same period (0.31, 0.17 to 0.57, P<0.001) and more likely to report erectile dysfunction (2.58, 1.09 to 6.11, P<0.05). Sexual dysfunction was not associated with BMI among women. Obese women aged under 30 were less likely to seek healthcare services for contraception (0.37, 0.18 to 0.76) or to use oral contraceptives (0.34, 0.15 to 0.78). They were also more likely to report an unintended pregnancy (4.26, 2.21 to 8.23).

CONCLUSION

There is a link between BMI and sexual behaviour and adverse sexual health outcomes, with obese women less likely to access contraceptive healthcare services and having more unplanned pregnancies. Prevention of unintended pregnancies among these women is a major reproductive health challenge. Healthcare professionals need to be aware of sensitivities related to weight and gender in the provision of sexual health services.