The combined oral contraceptive pill -- recent developments, risks and benefits

The introduction of the birth control pill as an effective, coitally-independent method of contraception was a public health milestone of the last century. Over time, combined oral contraception (COC) formulations and pill-taking regimens have evolved with improved safety and tolerability while maintaining contraceptive efficacy. In addition to protection against pregnancy, use of combined oral contraception confers a number of significant non-contraceptive benefits to users. COC use is also associated with well-studied risks. Common side effects are generally self-limiting and improve with increasing duration of use while serious adverse events, including venous thromboembolism, are rare among healthy COC users. Contraceptive decision-making should include consideration of both the risks and benefits of a given method versus the real consequences of unintended pregnancy.

Steroidal contraceptives: effect on bone fractures in women

BACKGROUND

Steroidal contraceptive use has been associated with changes in bone mineral density in women. Whether such changes increase the risk of fractures later in life is not clear. Osteoporosis is a major public health concern. Age-related decline in bone mass increases the risk of fracture, especially of the spine, hip, and wrist. Concern about bone health influences the recommendation and use of these effective contraceptives globally.

OBJECTIVES

Our aim was to evaluate the effect of using hormonal contraceptives before menopause on the risk of fracture in women.

SEARCH METHODS

Through April 2014, we searched for studies of fracture or bone health and hormonal contraceptives in MEDLINE, POPLINE, CENTRAL, EMBASE, and LILACS, as well as ClinicalTrials.gov and ICTRP. We examined reference lists of relevant articles for other trials. For the initial review, we wrote to investigators to find additional trials.

SELECTION CRITERIA

Randomized controlled trials (RCTs) were considered if they examined fractures, bone mineral density (BMD), or bone turnover markers in women with hormonal contraceptive use prior to menopause. Eligible interventions included comparisons of a hormonal contraceptive with a placebo or with another hormonal contraceptive that differed in terms of drug, dosage, or regimen. They also included providing a supplement to one group.

DATA COLLECTION AND ANALYSIS

We assessed all titles and abstracts identified through the literature searches. Mean differences were computed using the inverse variance approach. For dichotomous outcomes, the Mantel-Haenszel odds ratio (OR) was calculated. Both included the 95% confidence interval (CI) and used a fixed-effect model. Due to differing interventions, no trials could be combined for meta-analysis. We applied principles from GRADE to assess the evidence quality and address confidence in the effect estimates. In addition, a sensitivity analysis included trials that provided sufficient data for this review and evidence of at least moderate quality.

MAIN RESULTS

We found 19 RCTs that met our eligibility criteria. Eleven trials compared different combined oral contraceptives (COCs) or regimens of COCs; five examined an injectable versus another injectable, implant, or IUD; two studied implants, and one compared the transdermal patch versus the vaginal ring. No trial had fracture as an outcome. BMD was measured in 17 studies and 12 trials assessed biochemical markers of bone turnover. Depot medroxyprogesterone acetate (DMPA) was associated with decreased bone mineral density (BMD). The placebo-controlled trials showed BMD increases for DMPA plus estrogen supplement and decreases for DMPA plus placebo supplement. COCs did not appear to negatively affect BMD, and some formulations had more positive effects than others. However, no COC trial was placebo-controlled. Where studies showed differences between groups in bone turnover markers, the results were generally consistent with those for BMD. For implants, the single-rod etonogestrel group showed a greater BMD decrease versus the two-rod levonorgestrel group but results were not consistent across all implant comparisons.The sensitivity analysis included 11 trials providing evidence of moderate or high quality. Four trials involving DMPA showed some positive effects of an estrogen supplement on BMD, a negative effect of DMPA-subcutaneous on lumbar spine BMD, and a negative effect of DMPA on a bone formation marker. Of the three COC trials, one had a BMD decrease for the group with gestodene plus EE 15 μg. Another indicated less bone resorption in the group with gestodene plus EE 30 μg versus EE 20 μg.

AUTHORS' CONCLUSIONS

Whether steroidal contraceptives influence fracture risk cannot be determined from existing information. The evidence quality was considered moderate overall, largely due to the trials of DMPA, implants, and the patch versus ring. The COC evidence varied in quality but was low overall. Many trials had small numbers of participants and some had large losses. Health care providers and women should consider the costs and benefits of these effective contraceptives. For example, injectable contraceptives and implants provide effective, long-term birth control yet do not involve a daily regimen. Progestin-only contraceptives are considered appropriate for women who should avoid estrogen due to medical conditions.

[Heart, arteries and women, a care pathway for women at high cardiovascular risk]

Cardiovascular (CV) diseases are the primary cause of death of women. Since they kill 10 times more than breast cancer, preventive measures should be implemented. According to U.S. recommendations, a woman is either at "CV risk" or at "optimal health status" if she has no risk factors and a perfectly healthy lifestyle. Some risk factors are more deleterious to women (smoking, diabetes, stress, depression, atrial fibrillation); or specific to women (preeclampsia, gestational diabetes, contraception, menopause, headaches). The lifestyle plays a key role for them. The blood pressure measurement is the most frequent opportunity to detect women at risk. CV tests should be performed to all symptomatic women and for those over the age of 45 who want to start practicing sport. The cardiologist can play a key role to improve women's CV health by integrating their hormonal risks. Women themselves can also make a powerful contribution to prevention by adopting a healthy lifestyle. From those recommendations concerning women's CV health, there is a great opportunity to initiate a health path for women at high cardiovascular risk. The objectives of the specific path "heart, arteries and women" of University hospital of Lille will be to improve professional practice, awareness of women, educate public authorities and within a few years reduce the epidemic of CVD of French women.

Routine tests of haemostasis and low-oestrogen oral contraceptives: what to expect?

BACKGROUND

Frequent requests from gynaecologists for testing of haemostatic parameters in women using hormonal contraception in order to predict development of thromboembolic disease, along with advancement of testing quality and accuracy, created the need to assess and compare the overall effect of oral contraceptives on today's routine haemostatic tests.

METHODS

This 6-month prospective study included 195 women, first time users of oral contraceptives or with at least a 3-month pause before their entry in the study. Haemostatic changes were assessed by the following tests performed at three study time-points: at baseline, after three and after six months of taking oral contraceptives: prothrombin time, activated partial thromboplastin time, fibrinogen, resistance to activated protein C ratio, protein C activity, protein S activity, FVIII activity, antithrombin activity, plasminogen activity, alpha2-antiplasmin activity, inhibitor of plasminogen activator type 1 (PAI-1), and D-dimers. In addition, study subjects underwent genetic testing for FV Leiden mutation, FII G20210A mutation, and PAI-1 4G/5G polymorphism.

RESULTS

Significant changes were found in all haemostatic variables except for FVIII activity. With in-depth analysis, we showed that PAI-1 concentration decreased only in subjects with PAI-1 4G/5G genotype. None of the subjects developed venous thromboembolic disease during the study.

CONCLUSIONS

As most changes were within reference ranges, routine laboratory testing still does not appear to be recommendable in women without a known risk of thromboembolic disease.

ABCB4 mutations underlie hormonal cholestasis but not pediatric idiopathic gallstones

AIM: To investigate the contribution of ABCB4 mutations to pediatric idiopathic gallstone disease and the potential of hormonal contraceptives to prompt clinical manifestations of multidrug resistance protein 3 deficiency.

METHODS: Mutational analysis of ABCB4, screening for copy number variations by multiplex ligation-dependent probe amplification, genotyping for low expression allele c.1331T>C of ABCB11 and genotyping for variation c.55G>C in ABCG8 previously associated with cholesterol gallstones in adults was performed in 35 pediatric subjects with idiopathic gallstones who fulfilled the clinical criteria for low phospholipid-associated cholelithiasis syndrome (LPAC, OMIM #600803) and in 5 young females with suspected LPAC and their families (5 probands, 15 additional family members). The probands came to medical attention for contraceptive-associated intrahepatic cholestasis.

RESULTS: A possibly pathogenic variant of ABCB4 was found only in one of the 35 pediatric subjects with idiopathic cholesterol gallstones whereas 15 members of the studied 5 LPAC kindreds were confirmed and another one was highly suspected to carry predictably pathogenic mutations in ABCB4. Among these 16, however, none developed gallstones in childhood. In 5 index patients, all young females carrying at least one pathogenic mutation in one allele of ABCB4, manifestation of LPAC as intrahepatic cholestasis with elevated serum activity of gamma-glutamyltransferase was induced by hormonal contraceptives. Variants ABCB11 c.1331T>C and ABCG8 c.55G>C were not significantly overrepresented in the 35 examined patients with suspect LPAC.

CONCLUSION: Clinical criteria for LPAC syndrome caused by mutations in ABCB4 cannot be applied to pediatric patients with idiopathic gallstones. Sexual immaturity even prevents manifestation of LPAC.

Hormonal contraception for women exposed to HIV infection

BACKGROUND

Concern about a possible association of hormonal contraception with HIV acquisition has been raised by three types of evidence. Firstly, high-dose progestogen treatment greatly increases HIV acquisition in female non-human primates. Secondly, biological plausibility for a link between hormonal contraception anf HIV acquisition is provided by evidence of a hypo-oestrogenic state induced by progestogen contraception with vaginal mucosal thinning, and evidence of effects on the humoral and cellular immune systems. Thirdly, some but not other large observational studies have found an increase in HIV acquisition among women using hormonal contraception.

OBJECTIVES

To determine, from the best available evidence, the effect of hormonal contraception on HIV acquisition.

SEARCH METHODS

We used the Cochrane Fertility Regulation Group trials search strategy.

SELECTION CRITERIA

Published, unpublished and ongoing trials with random allocation, comparing hormonal with non-hormonal methods, other hormonal methods or no contraception in women at risk of HIV acquisition.

DATA COLLECTION AND ANALYSIS

Data will be extracted from eligible trials onto a data extraction sheet and analysed using routine Cochrane Collaboration methodology,

MAIN RESULTS

One ongoing randomised trial was identified, with no data available to date.

AUTHORS' CONCLUSIONS

There is currently no robust evidence from randomized trials on the possible effect of hormonal contraception on HIV acquisition. High quality trials in this area are needed to inform counselling of individual woman and public health policy.

Hormonal therapy deregulates prostaglandin-endoperoxidase synthase 2 (PTGS2) expression in endometriotic tissues

CONTEXT

Endometriosis is a common gynecologic condition characterized by an important inflammatory process mediated by the prostaglandin pathway. Oral contraceptives are the treatment of choice for symptomatic endometriotic women. However the effects of oral contraceptives use and prostaglandin pathway in endometriotic women are actually still unknown.

OBJECTIVE

To investigate the expression of prostaglandin pathway key genes in endometriotic tissue, affected or not by hormonal therapy, as compared with healthy endometrial tissue.

DESIGN

This was a comparative laboratory study.

SETTING

This study was conducted in a tertiary-care university hospital.

PATIENTS

Seventy-six women, with (n = 46) and without (n = 30) histologically proven endometriosis.

MAIN OUTCOME MEASURES

Prostaglandin-endoperoxidase synthase (PTGS)1, PTGS2, prostaglandin E receptor (PTGER)1, PTGER2, PTGER3, and PTGER4 mRNA levels in endometrium of disease-free women and in eutopic and ectopic endometrium of endometriosis-affected women. PTGS2 expression was further investigated by immunohistochemistry, using specific monoclonal antibodies. PTGS2 expression was analyzed at mRNA and protein levels and correlated with taking hormonal treatment.

RESULTS

PTGS2 expression was significantly increased in eutopic and ectopic endometrium as compared with healthy tissue (induction of 9.6- and 6.3-fold, respectively; P = .001). PTGS2 immunoreactivity increased gradually from normal endometrium to eutopic and ectopic endometrium (h-score of 96.7 ± 55.0, 128.3 ± 66.1, and 226.7 ± 62.6, respectively, P < .001). PTGER2, PTGER3, and PTGER4 expression increased significantly and gradually from normal to eutopic and ectopic endometrium, whereas PTGER1 remained unchanged. Patients under hormonal treatment had a higher PTGS2 expression at transcriptional and protein levels as compared with those without treatment (P = .002 and P = .025, respectively).

CONCLUSIONS

Prostaglandin pathway is strongly deregulated in eutopic and ectopic endometrium of women suffering from endometriosis for the benefit of an increased PTGS2 expression. We show for the first time that hormonal treatment appears to enhance even more PTGS2 expression. These results contribute to explain why medical treatment could fail to control endometriosis progression.

Combination contraceptives: effects on weight

BACKGROUND

Weight gain is often considered a side effect of combination hormonal contraceptives, and many women and clinicians believe that an association exists. Concern about weight gain can limit the use of this highly effective method of contraception by deterring the initiation of its use and causing early discontinuation among users. However, a causal relationship between combination contraceptives and weight gain has not been established.

OBJECTIVES

The aim of the review was to evaluate the potential association between combination contraceptive use and changes in weight.

SEARCH METHODS

In November 2013, we searched the computerized databases CENTRAL (The Cochrane Library), MEDLINE, POPLINE, EMBASE, and LILACS for studies of combination contraceptives, as well as ClinicalTrials.gov and International Clinical Trials Registry Platform (ICTRP). For the initial review, we also wrote to known investigators and manufacturers to request information about other published or unpublished trials not discovered in our search.

SELECTION CRITERIA

All English-language, randomized controlled trials were eligible if they had at least three treatment cycles and compared a combination contraceptive to a placebo or to a combination contraceptive that differed in drug, dosage, regimen, or study length.

DATA COLLECTION AND ANALYSIS

All titles and abstracts located in the literature searches were assessed. Data were entered and analyzed with RevMan. A second author verified the data entered. For continuous data, we calculated the mean difference and 95% confidence interval (CI) for the mean change in weight between baseline and post-treatment measurements using a fixed-effect model. For categorical data, such as the proportion of women who gained or lost more than a specified amount of weight, the Peto odds ratio with 95% CI was calculated.

MAIN RESULTS

We found 49 trials that met our inclusion criteria. The trials included 85 weight change comparisons for 52 distinct contraceptive pairs (or placebos). The four trials with a placebo or no intervention group did not find evidence supporting a causal association between combination oral contraceptives or a combination skin patch and weight change. Most comparisons of different combination contraceptives showed no substantial difference in weight. In addition, discontinuation of combination contraceptives because of weight change did not differ between groups where this was studied.

AUTHORS' CONCLUSIONS

Available evidence was insufficient to determine the effect of combination contraceptives on weight, but no large effect was evident. Trials to evaluate the link between combination contraceptives and weight change require a placebo or non-hormonal group to control for other factors, including changes in weight over time.

The incidence of venous thromboembolism (VTE)--after hip arthroscopy

PURPOSE

The purpose of this study was to determine the incidence of venous thromboembolism (VTE) after hip arthroscopy.

METHODS

Over the course of 13 months, four surgeons that routinely perform hip arthroscopy participated in a protocol to screen all patients postoperatively for deep venous thrombosis (DVT) using bilateral venous duplex ultrasound at or about the 2 week postoperative time point. All patients were assessed and stratified for VTE risk prior to surgery. Mechanical intraoperative and postoperative chemoprophylaxis were not administered. Perioperative factors, such as weightbearing status after surgery, traction time, and anesthesia type, were recorded.

RESULTS

We identified 139 eligible patients (average age 37.7, SD = 12.0) that underwent hip arthroscopy. The incidence of symptomatic VTE was 1.4 percent (2/139). Of the entire patient pool, 81 obtained a follow-up ultrasound. There were no cases of asymptomatic deep vein thrombosis (DVT). There were two symptomatic venous thromboembolic events noted; one DVT and one pulmonary embolus. One patient had no risk factors; the other was overweight and routinely took oral contraceptives. Amongst the patient cohort, the mean BMI was 25.9 (SD = 4.8). The mean traction time was 58.9 minutes (SD = 23.1). Most patients (71%) were partial weightbearing after the procedure.

CONCLUSION AND CLINICAL RELEVANCE

In patients undergoing hip arthroscopy, the rate of postoperative VTE was low, despite the use of prolonged axial traction and surgical proximity to the pelvic veins. Although patients should be counseled preoperatively regarding the risk of VTE, we believe that routine use of pharmacologic prophylaxis is not indicated following hip arthroscopy if patients are properly risk stratified prior to surgery and found to be at low risk for VTE.

Normal breast physiology: the reasons hormonal contraceptives and induced abortion increase breast-cancer risk

A woman gains protection from breast cancer by completing a full-term pregnancy. In utero, her offspring produce hormones that mature 85 percent of the mother's breast tissue into cancer-resistant breast tissue. If the pregnancy ends through an induced abortion or a premature birth before thirty-two weeks, the mother's breasts will have only partially matured, retaining even more cancer-susceptible breast tissue than when the pregnancy began. This increased amount of immature breast tissue will leave the mother with more sites for cancer initiation, thereby increasing her risk of breast cancer. Hormonal contraceptives increase breast-cancer risk by their proliferative effect on breast tissue and their direct carcinogenic effects on DNA. Hormonal contraceptives include estrogen-progestin combination drugs prescribed in any manner of delivery: orally, transdermally, vaginally, or intrauterine. This article provides the detailed physiology and data that elucidate the mechanisms through which induced abortion and hormonal contraceptives increase breast-cancer risk.

Impact of alcohol consumption and cigarette smoke on renal function and select serum elements in female subjects using combined oral contraceptive

Drugs and life style choices such as alcohol consumption and smoking are capable of independently altering levels of essential trace elements as well as tissue or organ function. The purpose of the study is to determine how differences in degree of exposure to cigarette smoke and alcohol consumption will alter serum magnesium (Mg), Cobalt (Co) and Manganese (Mn) levels in female subjects using combined oral contraceptives. Thirty female subjects who have used combined oral contraceptive for at least 5 years as well as 30 age-matched control women who are using rhythm method as birth control method were recruited from drinking joints/bars by random sampling technique. Serum trace element concentrations were determined using atomic absorption spectrometry and K+, Na+, albumin, globulin, total protein, urea and creatinine were also determined. Data obtained were analyzed using Student't' test, Pearson's correlation coefficient and Multivariate Analysis of Variance (MANOVA). Na+ was significantly higher in combined oral contraceptive users compared with controls (p&lt;0.05), whereas Mg was decreased (p&lt;0.05). Co, Mn, urea, creatinine, total protein, albumin, globulin, K+ were not significantly different in combined oral contraceptive users compared with the controls (p&gt;0.05). MANOVA results revealed that binge drinkers/smokers group recorded a significant lower (p&lt;0.05) magnesium level than the passive smokers/social drinkers group and controls. The results of this study suggest that subjects using combined oral contraceptive, consuming alcohol and exposed to cigarette smoke may be at greater risks of diseases linked with magnesium depletion.

Oral contraceptives and the periodontium

Oral contraceptives are a safe and effective means of contraception for millions of women worldwide. The first formulations of these drugs contained much higher doses of estrogens and progestins than those available today, and these were associated with an unacceptably high rate of unwanted effects including serious cardiovascular events. In addition, a number of case reports and clinical studies suggested that use of the first generation oral contraceptives was also associated with an increased risk for gingival and/or periodontal disease. Unfortunately, many of these early studies suffered from significant methodological flaws which throw their findings into question. Nonetheless, these studies provided the basis for a perception among the dental profession that oral contraceptives increase the risk for gingivitis and/or periodontitis. Realisation that the adverse events profile of oral contraceptives was dose dependant led to the development of the modern low dose formulations that are in use today. There have been far fewer studies to investigate whether modern oral contraceptives have any impact on the periodontium compared to studies of the early contraceptive formulations, but the quality of the more recent research is undoubtedly better. Following extensive review of the relevant literature and consideration of the historical perspective, the best available evidence strongly supports that oral contraceptives no longer place users at any increased risk for gingivitis or periodontitis. Oral contraceptives should not be viewed as a risk factor for gingival or periodontal disease.

Progestin-only pills for contraception

BACKGROUND

The introduction of a new progestin-only oral contraceptive in Europe has renewed interest in this class of oral contraceptives. Unlike the more widely used combined oral contraceptives containing an estrogen plus progestin, these pills contain only a progestin (progestogen) and are taken without interruption. How these pills compare to others in their class or to combined oral contraceptives is not clear.

OBJECTIVES

This review examined randomized controlled trials of progestin-only pills for differences in efficacy, acceptability, and continuation rates.

SEARCH METHODS

Through October 2013, we searched the computerized databases MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), POPLINE, and LILACS for studies of progestin-only pills. We also searched for current trials via ClinicalTrials.gov and ICTRP. Previous searches also included EMBASE.

SELECTION CRITERIA

We included all randomized controlled trials in any language that included progestin-only pills for contraception.  We incorporated any comparison with a progestin-only pill; this could include different doses, other progestin-only pills, combined oral contraceptives, or other contraceptives.

DATA COLLECTION AND ANALYSIS

The first author abstracted the data and entered the information into RevMan 5. Another author performed a second, independent data abstraction to verify the initial data entry.We attempted to extract life-table rates (actuarial or continuous) and used the rate difference as the effect measure. Where life-table rates were not published, we used the incidence rate ratio (ratio of Pearl rates). Where only the crude number of events was published, we calculated the Peto odds ratio with 95% confidence interval (CI) using a fixed-effect model. For continuous variables, the mean difference (MD) was computed with 95% CI. Because of disparate exposures, we were not able to combine studies in meta-analysis.

MAIN RESULTS

Six trials met the inclusion criteria. We have not found any new studies since the initial review. In the trial comparing the desogestrel versus levonorgestrel progestin-only pill, desogestrel was not associated with a significantly lower risk of accidental pregnancy; the rate ratio was 0.27 (95% CI 0.06 to 1.19). However, the desogestrel progestin-only pill caused more bleeding problems, although this difference was not statistically significant. The trial comparing low-dose mifepristone versus a levonorgestrel progestin-only pill found similar pregnancy rates. In the trial comparing ethynodiol diacetate versus a combined oral contraceptive, irregular cycles occurred in all women assigned to the progestin-only pill (odds ratio 135.96; 95% CI 7.61 to 2421.02). In a trial comparing two progestin-only and two combined oral contraceptives, the progestin-only pill containing levonorgestrel 30 μg had higher efficacy than did the pill containing norethisterone 350 μg. An early trial found megestrol acetate inferior to other progestin-only pills in terms of efficacy. A study of the timing of pill initiation after birth found no important differences, but high losses to follow up undermined the trial.

AUTHORS' CONCLUSIONS

Evidence is insufficient to compare progestin-only pills to each other or to combined oral contraceptives.

Hormonal contraception and pelvic girdle pain during pregnancy: a population study of 91,721 pregnancies in the Norwegian Mother and Child Cohort

STUDY QUESTION

Is pre-pregnancy hormonal contraception use associated with the development of pelvic girdle pain during pregnancy?

SUMMARY ANSWER

In contrast to combined oral contraceptive pills, long lifetime exposure to progestin-only contraceptive pills or the use of a progestin intrauterine device during the final year before pregnancy were associated with pelvic girdle pain.

WHAT IS ALREADY KNOWN

Pelvic girdle pain severely affects many women during pregnancy. Smaller studies have suggested that hormonal contraceptive use is involved in the underlying mechanisms, but evidence is inconclusive.

STUDY DESIGN, SIZE, DURATION

A population study during the years 1999-2008.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 91,721 pregnancies included in the Norwegian Mother and Child Cohort Study. Data were obtained by two self-administered questionnaires during pregnancy weeks 17 and 30.

MAIN RESULTS AND THE ROLE OF CHANCE

Pelvic girdle pain was present in 12.9% of women who had used combined oral contraceptive pills during the last pre-pregnancy year, 16.4% of women who had used progestin-only contraceptive pills, 16.7% of women who had progestin injections and 20.7% of women who had used progestin intrauterine devices, compared with 15.3% of women who did not report use of hormonal contraceptives. After adjustment for other study factors, the use of a progestin intrauterine device was the only factor based on the preceding year associated with pelvic girdle pain [adjusted odds ratios (OR) 1.20; 95% confidence interval (CI): 1.11-1.31]. Long lifetime exposure to progestin-only contraceptive pills was also associated with pelvic girdle pain (adjusted OR 1.49; 95% CI: 1.01-2.20).

LIMITATIONS, REASONS FOR CAUTION

The participation rate was 38.5%. However, a recent study on the potential biases of skewed selection in the Norwegian Mother and Child Cohort Study found the prevalence estimates but not the exposure-outcome associations to be influenced by the selection.

WIDER IMPLICATIONS OF THE FINDINGS

The results suggest that combined oral contraceptives can be used without fear of developing pelvic girdle pain during pregnancy. However, the influence of progestin intrauterine devices and long-term exposure to progestin-only contraceptive pills requires further study.

STUDY FUNDING/COMPETING INTEREST(S)

The present study was supported by the Norwegian Research Council. None of the authors has a conflict of interest.

Strategies to improve adherence and acceptability of hormonal methods of contraception

BACKGROUND

Worldwide, hormonal contraceptives are among the most popular reversible contraceptives. Despite their high theoretical effectiveness, typical use results in much lower effectiveness. In large part, this disparity reflects difficulties in adherence to the contraceptive regimen and low rates for long-term continuation.

OBJECTIVES

The intent was to determine the effectiveness of ancillary counseling techniques to improve adherence to, and continuation of, hormonal methods of contraception.

SEARCH METHODS

Through August 2013, we searched computerized databases for randomized controlled trials (RCTs) comparing client-provider interventions with standard family planning counseling. Sources included CENTRAL, MEDLINE, EMBASE, POPLINE, ClinicalTrials.gov and ICTRP. Earlier searches also included LILACS, PsycINFO, Dissertation Abstracts, African Index Medicus, and IMEMR.

SELECTION CRITERIA

We included RCTs of an intensive counseling technique or other client-provider intervention compared to routine family planning counseling. Interventions included group motivation; structured, peer, or multi-component counseling; and intensive reminders of appointments or next dosing. Outcome measures were discontinuation, reasons for discontinuation, number of missed pills or on-time injections, and pregnancy.

DATA COLLECTION AND ANALYSIS

One author evaluated the titles and abstracts from the searches to determine eligibility. Two authors extracted data from the included studies. We calculated the Mantel-Haenszel odds ratio (OR) for dichotomous outcomes. For continuous variables, the mean difference (MD) was computed; RevMan uses the inverse variance approach. For all analyses, 95% confidence intervals (CI) were also computed. Since the studies identified differed in both interventions and outcome measures, we did not conduct a meta-analysis.

MAIN RESULTS

Nine RCTs met our inclusion criteria. Five involved direct counseling; of those, two also provided multiple contacts by telephone. Four other trials provided intensive reminders, two of which also provided health education information. Three trials showed some benefit of the experimental intervention. In a counseling intervention, women who received repeated structured information about the injectable depot medroxyprogesterone acetate (DMPA) were less likely to discontinue the method by 12 months (OR 0.27; 95% CI 0.16 to 0.44) than women who had routine counseling. The intervention group was also less likely to discontinue due to menstrual disturbances (OR 0.20; 95% CI 0.11 to 0.37). Another trial showed a group with special counseling plus phone calls was more likely than the special-counseling group to report consistent use of oral contraceptives (OC) at 3 months (OR 1.41; 95% CI 1.06 to 1.87), though not at 12 months. The group with only special counseling did not differ significantly from those with standard care for any outcome. The third trial compared daily text-message reminders about OCs plus health information versus standard care. Women in the text-message group were more likely than the standard-care group to continue OC use by six months (OR 1.54; 95% CI 1.14 to 2.10). The text-message group was also more likely to avoid an interruption in OC use longer than seven days (OR 1.53; 95% CI 1.13 to 2.07).

AUTHORS' CONCLUSIONS

Only three trials showed some benefit of strategies to improve adherence and continuation. However, several had small sample sizes and six had high losses to follow up. The overall quality of evidence was considered moderate. The intervention type and intensity varied greatly across the studies. A combination of intensive counseling and multiple contacts and reminders may be needed to improve adherence and acceptability of contraceptive use. High-quality RCTs with adequate power and well-designed interventions could help identify ways to improve adherence to, and continuation of, hormonal contraceptive methods.

Toward a new concept of "natural balance" in oral estroprogestin contraception

The Pill has undergone many changes since its first appearance some 50 years ago. Key developments included the reduction of ethinylestradiol doses and the synthesis of new progestins in order to increase safety, compliance and efficiency. Low-dose combined oral contraceptives (COCs) are currently the preferred option for millions of women. Due to this widespread use, it has been argued that the safety of COCs should be even better, raising the threshold for excellence. Yet in spite of major improvements, there is still an associated risk of venous thromboembolism (VTE). The next step in COCs' evolution should take total estrogenicity and hepatic estro-androgenic balance into account. The focus on the estrogen component--which has not changed in 50 years--has yielded a new class of natural estrogen pills. Following the introduction of a first quadriphasic pill, a monophasic estradiol pill based on the concept of "natural balance" was subsequently made available. These recent achievements could represent a step forward in the evolution of COCs and pave the way for better safety.

Different combined oral contraceptives and the risk of venous thrombosis: systematic review and network meta-analysis

OBJECTIVE

To provide a comprehensive overview of the risk of venous thrombosis in women using different combined oral contraceptives.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

PubMed, Embase, Web of Science, Cochrane, Cumulative Index to Nursing and Allied Health Literature, Academic Search Premier, and ScienceDirect up to 22 April 2013.

REVIEW METHODS

Observational studies that assessed the effect of combined oral contraceptives on venous thrombosis in healthy women. The primary outcome of interest was a fatal or non-fatal first event of venous thrombosis with the main focus on deep venous thrombosis or pulmonary embolism. Publications with at least 10 events in total were eligible. The network meta-analysis was performed using an extension of frequentist random effects models for mixed multiple treatment comparisons. Unadjusted relative risks with 95% confidence intervals were reported. The requirement for crude numbers did not allow adjustment for potential confounding variables.

RESULTS

3110 publications were retrieved through a search strategy; 25 publications reporting on 26 studies were included. Incidence of venous thrombosis in non-users from two included cohorts was 1.9 and 3.7 per 10,000 woman years, in line with previously reported incidences of 1-6 per 10,000 woman years. Use of combined oral contraceptives increased the risk of venous thrombosis compared with non-use (relative risk 3.5, 95% confidence interval 2.9 to 4.3). The relative risk of venous thrombosis for combined oral contraceptives with 30-35 µg ethinylestradiol and gestodene, desogestrel, cyproterone acetate, or drospirenone were similar and about 50-80% higher than for combined oral contraceptives with levonorgestrel. A dose related effect of ethinylestradiol was observed for gestodene, desogestrel, and levonorgestrel, with higher doses being associated with higher thrombosis risk.

CONCLUSION

All combined oral contraceptives investigated in this analysis were associated with an increased risk of venous thrombosis. The effect size depended both on the progestogen used and the dose of ethinylestradiol.

Comparison of pooled risk estimates for adverse effects from different observational study designs: methodological overview

BACKGROUND

A diverse range of study designs (e.g. case-control or cohort) are used in the evaluation of adverse effects. We aimed to ascertain whether the risk estimates from meta-analyses of case-control studies differ from that of other study designs.

METHODS

Searches were carried out in 10 databases in addition to reference checking, contacting experts, and handsearching key journals and conference proceedings. Studies were included where a pooled relative measure of an adverse effect (odds ratio or risk ratio) from case-control studies could be directly compared with the pooled estimate for the same adverse effect arising from other types of observational studies.

RESULTS

We included 82 meta-analyses. Pooled estimates of harm from the different study designs had 95% confidence intervals that overlapped in 78/82 instances (95%). Of the 23 cases of discrepant findings (significant harm identified in meta-analysis of one type of study design, but not with the other study design), 16 (70%) stemmed from significantly elevated pooled estimates from case-control studies. There was associated evidence of funnel plot asymmetry consistent with higher risk estimates from case-control studies. On average, cohort or cross-sectional studies yielded pooled odds ratios 0.94 (95% CI 0.88-1.00) times lower than that from case-control studies.

INTERPRETATION

Empirical evidence from this overview indicates that meta-analysis of case-control studies tend to give slightly higher estimates of harm as compared to meta-analyses of other observational studies. However it is impossible to rule out potential confounding from differences in drug dose, duration and populations when comparing between study designs.

20 µg versus >20 µg estrogen combined oral contraceptives for contraception

BACKGROUND

Concern about estrogen-related adverse effects has led to progressive reductions in the estrogen dose in combination oral contraceptives (COCs). However, reducing the amount of estrogen to improve safety could result in decreased contraceptive effectiveness and unacceptable changes in bleeding patterns.

OBJECTIVES

To test the hypothesis that COCs containing ≤ 20 μg ethinyl estradiol (EE) perform similarly as those containing > 20 μg in terms of contraceptive effectiveness, bleeding patterns, discontinuation, and side effects.

SEARCH METHODS

In July 2013, we searched CENTRAL, MEDLINE, and POPLINE, and examined references of potentially eligible trials. We also searched for recent clinical trials using ClinicalTrials.gov and ICTRP. No new trials met the inclusion criteria. Previous searches included EMBASE. For the initial review, we wrote to oral contraceptive manufacturers to identify trials.

SELECTION CRITERIA

English-language reports of randomized controlled trials were eligible that compare a COC containing ≤ 20 μg EE with a COC containing > 20 μg EE. We excluded studies where the interventions were designed to be administered for less than three consecutive cycles or to be used primarily as treatment for non-contraceptive conditions. Trials had to report on contraceptive effectiveness, bleeding patterns, trial discontinuation due to bleeding-related reasons or other side effects, or side effects to be included in the review.

DATA COLLECTION AND ANALYSIS

One author evaluated all titles and abstracts from literature searches to determine whether they met the inclusion criteria. Two authors independently extracted data from studies identified for inclusion. We wrote to the researchers when additional information was needed. Data were entered and analyzed with RevMan.

MAIN RESULTS

No differences were found in contraceptive effectiveness for the 13 COC pairs for which this outcome was reported. Compared to the higher-estrogen pills, several COCs containing 20 μg EE resulted in higher rates of early trial discontinuation (overall and due to adverse events such as irregular bleeding) as well as increased risk of bleeding disturbances (both amenorrhea or infrequent bleeding and irregular, prolonged, frequent bleeding, or breakthrough bleeding or spotting).

AUTHORS' CONCLUSIONS

While COCs containing 20 μg EE may be theoretically safer, this review did not focus on the rare events required to assess this hypothesis. Data from existing randomized controlled trials are inadequate to detect possible differences in contraceptive effectiveness. Low-dose estrogen COCs resulted in higher rates of bleeding pattern disruptions. However, most trials compared COCs containing different progestin types, and changes in bleeding patterns could be related to progestin type as well as estrogen dose. Higher follow-up rates are essential for meaningful interpretation of results.