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The Cochrane Database of Systematic... Aug 2016Progestin-only contraceptives (POCs) are appropriate for many women who cannot or should not take estrogen. POCs include injectables, intrauterine contraception,... (Review)
Review
BACKGROUND
Progestin-only contraceptives (POCs) are appropriate for many women who cannot or should not take estrogen. POCs include injectables, intrauterine contraception, implants, and oral contraceptives. 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
Until 4 August 2016, we searched MEDLINE, CENTRAL, POPLINE, LILACS, ClinicalTrials.gov, and ICTRP. For the initial review, we contacted investigators to identify other trials.
SELECTION CRITERIA
We considered comparative studies 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. Non-randomized studies (NRS) need to control for confounding factors. We used adjusted measures for the primary effects in NRS or the results of matched analysis from paired samples. If the report did not provide adjusted measures for the primary analysis, we used unadjusted outcomes. For RCTs and NRS without adjusted measures, we computed the mean difference (MD) with 95% confidence interval (CI) for continuous variables. For dichotomous outcomes, we calculated the Mantel-Haenszel odds ratio (OR) with 95% CI.
MAIN RESULTS
We found 22 eligible studies that included a total of 11,450 women. With 6 NRS added to this update, the review includes 17 NRS and 5 RCTs. By contraceptive method, the review has 16 studies of depot medroxyprogesterone acetate (DMPA), 4 of levonorgestrel-releasing intrauterine contraception (LNG-IUC), 5 for implants, and 2 for progestin-only pills.Comparison groups did not differ significantly for weight change or other body composition measure in 15 studies. Five studies with moderate or low quality evidence showed differences between study arms. Two studies of a six-rod implant also indicated some differences, but the evidence was low quality.Three studies showed differences for DMPA users compared with women not using a hormonal method. In a retrospective study, weight gain (kg) was greater for DMPA versus copper (Cu) IUC in years one (MD 2.28, 95% CI 1.79 to 2.77), two (MD 2.71, 95% CI 2.12 to 3.30), and three (MD 3.17, 95% CI 2.51 to 3.83). A prospective study showed adolescents using DMPA had a greater increase in body fat (%) compared with 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). A more recent retrospective study reported greater mean increases with use of DMPA versus Cu IUC for weight (kg) at years 1 (1.3 vs 0.2), 4 (3.5 vs 1.9), and 10 (6.6 vs 4.9).Two studies reported a greater mean increase in body fat mass (%) for POC users versus women not using a hormonal method. The method was LNG-IUC in two studies (reported means 2.5 versus -1.3; P = 0.029); (MD 1.60, 95% CI 0.45 to 2.75). One also studied a desogestrel-containing pill (MD 3.30, 95% CI 2.08 to 4.52). Both studies showed a greater decrease in lean body mass among POC users.
AUTHORS' CONCLUSIONS
We considered the overall quality of evidence to be low; more than half of the studies had low quality evidence. The main reasons for downgrading were lack of randomizations (NRS) and high loss to follow-up or early discontinuation.These 22 studies showed limited evidence of change in weight or body composition with use of POCs. Mean weight gain at 6 or 12 months was less than 2 kg (4.4 lb) for most studies. Those with multiyear data showed mean weight change was approximately twice as much at two to four years than at one year, but generally the study groups did not differ significantly. Appropriate counseling about typical weight gain may help reduce discontinuation of contraceptives due to perceptions of weight gain.
Topics: Adolescent; Adult; Body Composition; Body Weight; Contraceptives, Oral, Hormonal; Drug Implants; Female; Humans; Intrauterine Devices, Medicated; Levonorgestrel; Medroxyprogesterone Acetate; Progestins; Prospective Studies; Retrospective Studies; Weight Gain
PubMed: 27567593
DOI: 10.1002/14651858.CD008815.pub4 -
The Cochrane Database of Systematic... Aug 2016Obesity has reached epidemic proportions around the world. Effectiveness of hormonal contraceptives may be related to metabolic changes in obesity or to greater body... (Meta-Analysis)
Meta-Analysis Review
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.
Topics: Body Mass Index; Body Weight; Contraception; Contraceptive Agents, Female; Female; Humans; Obesity; Overweight; Pregnancy; Pregnancy Rate; Pregnancy, Unplanned; Prospective Studies; Randomized Controlled Trials as Topic
PubMed: 27537097
DOI: 10.1002/14651858.CD008452.pub4 -
Journal of Pediatric and Adolescent... Dec 2016Adolescents are at high risk for unintended pregnancies. Although intrauterine devices (IUDs), long-acting reversible contraceptives (LARCs), are known to be highly... (Review)
Review
STUDY OBJECTIVE
Adolescents are at high risk for unintended pregnancies. Although intrauterine devices (IUDs), long-acting reversible contraceptives (LARCs), are known to be highly effective in preventing pregnancy, little is known about IUD adherence in adolescents. In this systematic review (SR) we examined IUD continuation rates compared with other forms of contraception in young women aged 25 years and younger. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: A systematic search of Ovid Medline, Cochrane Library, and Embase was conducted for the years 1946-2015. Included studies examined IUD use in women 25 years of age and younger, compared IUD use with another form of contraception, and measured continuation rates at 12 months. The quality of each study was appraised using the Downs and Black criteria, and 12-month continuation rates among studies were pooled and analyzed according to contraceptive type.
RESULTS
Of 3597 articles retrieved, 9 studies met criteria for SR. Synthesized across studies, 12-month continuation was significantly higher for IUD users (86.5%, 12,761/14,747) compared with oral contraceptives (39.6%, 1931/4873), Depo-Provera (Pfizer Inc, New York, NY) hormonal injection (39.8%, 510/1282), vaginal ring (48.9%, 196/401), and transdermal patch (39.8%, 37/93; all P values < .001). There was no statistically significant difference in 12-month continuation between the IUD and another LARC method, the subdermal etonogestrel implant (85.3%, 4671/5474).
CONCLUSION
Findings of this SR suggest that continuation rates for IUDs are generally higher compared with other contraceptive methods for women aged 25 years and younger. In a population with high rates of unintended pregnancies, generally low adherence, and imperfect use with other non-LARCs, IUD use should be encouraged.
Topics: Adolescent; Adult; Contraception; Contraception Behavior; Contraceptive Agents, Female; Contraceptive Devices, Female; Contraceptives, Oral; Desogestrel; Female; Humans; Intrauterine Devices; Medroxyprogesterone Acetate; Patient Compliance; Pregnancy; Pregnancy, Unplanned; Time Factors; Young Adult
PubMed: 27386754
DOI: 10.1016/j.jpag.2016.06.007 -
Contraception Dec 2016Women with depressive or bipolar disorders are at an increased risk for unintended pregnancy. (Review)
Review
BACKGROUND
Women with depressive or bipolar disorders are at an increased risk for unintended pregnancy.
OBJECTIVE
To examine the safety of hormonal contraception among women with depressive and bipolar disorders.
METHODS
We searched for articles published through January 2016 on the safety of using any hormonal contraceptive method among women with depressive or bipolar disorders, including those who had been diagnosed clinically or scored above threshold levels on a validated screening instrument. Outcomes included changes in symptoms, hospitalization, suicide and modifications in medication regimens such as increase or decrease in dosage or changes in type of drug.
RESULTS
Of 2376 articles, 6 met the inclusion criteria. Of three studies that examined women clinically diagnosed with depressive or bipolar disorder, one found that oral contraceptives (OCs) did not significantly change mood across the menstrual cycle among women with bipolar disorder, whereas mood did significantly change across the menstrual cycle among women not using OCs; one found no significant differences in the frequency of psychiatric hospitalizations among women with bipolar disorder who used depot medroxyprogesterone acetate (DMPA), intrauterine devices (IUDs) or sterilization; and one found no increase in depression scale scores among women with depression using and not using OCs, for both those treated with fluoxetine and those receiving placebo. Of three studies that examined women who met a threshold for depression on a screening instrument, one found that adolescent girls using combined OCs (COCs) had significantly improved depression scores after 3 months compared with placebo, one found that OC users had similar odds of no longer being depressed at follow-up compared with nonusers, and one found that COC users were less frequently classified as depressed over 11 months than IUD users.
CONCLUSIONS
Limited evidence from six studies found that OC, levonorgestrel-releasing IUD and DMPA use among women with depressive or bipolar disorders was not associated with worse clinical course of disease compared with no hormonal method use.
Topics: Bipolar Disorder; Contraceptives, Oral; Depressive Disorder; Equipment Safety; Female; Humans; Intrauterine Devices, Copper; Levonorgestrel; Medroxyprogesterone Acetate; Pregnancy; Pregnancy, Unplanned; Psychiatric Status Rating Scales; Risk Assessment
PubMed: 27364100
DOI: 10.1016/j.contraception.2016.06.012 -
Contraception Dec 2016Women with medical conditions associated with increased risk for thrombosis generally should not use estrogen-containing contraceptives; however, less is known about... (Review)
Review
BACKGROUND
Women with medical conditions associated with increased risk for thrombosis generally should not use estrogen-containing contraceptives; however, less is known about progestin-only contraceptives (POCs) and thrombosis risk.
OBJECTIVES
The objective was to identify evidence regarding the risk of venous thromboembolism (VTE) or arterial thromboembolism [stroke or acute myocardial infarction (AMI)] among women using POCs.
METHODS
We searched the PubMed database for all articles published from database inception through January 2016 for studies examining thrombosis among women using POCs. We included studies which examined women with medical conditions associated with thrombosis risk, as well as studies of women in the general population (either without these conditions or who were not specified to have these conditions). Hormonal contraceptives of interest included progestin-only pills (POPs), injectables, implants and levonorgestrel-releasing intrauterine devices (LNG-IUDs). Outcomes of interest included VTE, stroke and AMI.
RESULTS
There were 26 articles of good to poor quality that met inclusion criteria; 9 studies examined women with medical conditions and 20 examined women in the general population. Two studies found that, among smokers and women with certain thrombogenic mutations, use of depot medroxyprogesterone acetate (DMPA) had elevated odds of VTE compared with nonsmokers or those without mutations, although confidence intervals were wide and overlapped with odds among nonusers. One study found that, among women with previous VTE, use of POCs (including DMPA) was associated with a nonsignificant increased odds of recurrent VTE (all of which were among DMPA users); two other studies that examined POCs other than DMPA did not observe an association with recurrent VTE. Two studies found that use of DMPA among healthy women was also associated with increased odds of VTE. Two studies found that use of POCs for therapeutic indications was associated with increased odds of VTE. Studies did not find increased odds of VTE with POPs for contraceptive purposes, implants or LNG-IUDs nor were there increased odds of stroke or AMI with any POCs.
CONCLUSION
The majority of evidence identified by this systematic review did not suggest an increase in odds for venous or arterial events with use of most POCs. Limited evidence suggested increased odds of VTE with use of injectables (three studies) and use of POCs for therapeutic indications (two studies, one with POCs unspecified and the other with POPs). Any increase in risk likely translates to a small increase in absolute numbers of thrombotic events at the population level.
Topics: Contraception; Female; Humans; Myocardial Infarction; Progestins; Risk Assessment; Stroke; Venous Thromboembolism; Weight Gain
PubMed: 27153743
DOI: 10.1016/j.contraception.2016.04.014 -
BMJ Supportive & Palliative Care Sep 2016Cachexia describes a complex pathological syndrome of muscle wasting, anorexia and weight loss. Progesterone therapies have been shown to improve appetite and promote... (Review)
Review
BACKGROUND
Cachexia describes a complex pathological syndrome of muscle wasting, anorexia and weight loss. Progesterone therapies have been shown to improve appetite and promote weight gain in patients with cachexia; however, research has focused heavily on patients with cancer, and its effectiveness in other diseases remains unclear.
AIMS
This systematic review aimed to present the evidence available for progesterone therapy as a treatment for non-cancer cachexia.
METHOD
Surrogate outcome measures used were weight change, lean body mass (LBM), muscle strength, appetite, health-related quality of life (HRQOL) and serum albumin. Both randomised and non-randomised trials were included. A literature search of clinical trials using the medical subject heading (MeSH) terms 'cachexia' OR 'anorexia' OR 'weight' OR 'frail (truncated)' OR 'appetite' OR 'wasting syndrome' PLUS 'megestrol acetate' OR 'medroxyprogesterone acetate' was performed.
RESULTS
Eighteen studies were included in this review; 12 randomised control trials and 6 non-randomised trials. This collated results from 916 patients with HIV/AIDS, end-stage renal failure, chronic obstructive pulmonary disease (COPD) and geriatric cachexia. Meta-analysis comparing progesterone therapy with placebo concluded mean change in weight was not significant (mean difference (MD) 1.56, 95% CI -0.36 to 3.52, p=0.12). There was little evidence to show significant impact on LBM, and no trials looked at muscle strength. There was a paucity of evidence looking at appetite and HRQOL; however, results were generally positive.
CONCLUSIONS
Current evidence does not support the use of progesterone therapies for non-cancer cachexia. There may however be a limited role for its use as an appetite stimulant in a palliative context on a case-by-case basis.
Topics: Body Weight; Cachexia; Humans; Progesterone; Quality of Life; Randomized Controlled Trials as Topic; Treatment Outcome
PubMed: 27098973
DOI: 10.1136/bmjspcare-2015-001041 -
Contraception Sep 2016Depot medroxyprogesterone acetate (DMPA), a progestogen-only contraceptive injectable, has traditionally been formulated as a crystalline suspension delivered... (Review)
Review
CONTEXT
Depot medroxyprogesterone acetate (DMPA), a progestogen-only contraceptive injectable, has traditionally been formulated as a crystalline suspension delivered intramuscularly (IM) at a dose of 150mg/1.0mL. A new, lower dose formulation of DMPA (104mg/0.65mL) has been developed for subcutaneous administration (SC). Given its increasing global availability and public health relevance, DMPA-SC was prioritized for inclusion as a new method referenced in the World Health Organization (WHO) Medical Eligibility Criteria for Contraceptive Use (MEC), 5th Edition.
OBJECTIVE
This systematic review evaluated the published peer-reviewed literature regarding the safety of DMPA-SC among women with various characteristics or medical conditions. Results of this review informed the decision-making of a WHO Guideline Development Group in order to include recommendations on contraceptive eligibility within the revised MEC.
METHODS
We searched PubMed and Cochrane Library databases to identify all relevant evidence published in peer-reviewed journals regarding the safety of DMPA-SC when used by women of reproductive age, particularly those with select characteristics or conditions specified in the MEC, from inception through June 2015. The quality of each individual study was assessed using the system for grading evidence developed by the United States Preventive Services Task Force.
RESULTS
Fourteen studies met criteria for inclusion. Ten reported results relevant to DMPA users of varying age or with obesity, endometriosis or HIV; four compared the safety of DMPA-SC and DMPA-IM when used by general populations of healthy women. A randomized trial evaluating changes in bone mineral density among adult DMPA-SC and DMPA-IM users demonstrated no differences at 2years of follow-up. Limited evidence reported no consistent differences in weight change or bleeding patterns according to age; however, adolescents (<18years) were not included in any studies. Similar contraceptive efficacy, weight change, bleeding patterns and occurrence of other adverse effects among obese and nonobese DMPA-SC users were observed. Women with endometriosis using DMPA-SC over 6months had minimal decreases in bone mineral density, weight gain, few serious adverse events and experienced improved pain symptoms. Women living with HIV tolerated injection of DMPA-SC with rare complications. DMPA-SC and DMPA-IM also show therapeutic equivalence and similar effects on weight gain, changes in bleeding patterns and reports of other adverse effects when these different delivery systems were used by general populations of women.
CONCLUSION
Evidence for use of DMPA-SC by women with select conditions and characteristics including age, obesity, endometriosis or HIV demonstrates that this method can generally be used safely in these contexts. Further, DMPA-SC and DMPA-IM appear to be therapeutically equivalent with similar safety profiles when used by healthy women.
Topics: Bone Density; Contraceptive Agents, Female; Delayed-Action Preparations; Endometriosis; Female; HIV Infections; Humans; Injections, Intramuscular; Injections, Subcutaneous; Medroxyprogesterone Acetate; Obesity; Pain; Patient Satisfaction; Practice Guidelines as Topic; Randomized Controlled Trials as Topic; Weight Gain; World Health Organization
PubMed: 26874275
DOI: 10.1016/j.contraception.2016.02.003 -
Clinical Obstetrics and Gynecology Mar 2016Fibroids are the most common tumor of the female reproductive tract, but approved medical treatments are limited. Patients demand uterine-sparing treatments which... (Review)
Review
Fibroids are the most common tumor of the female reproductive tract, but approved medical treatments are limited. Patients demand uterine-sparing treatments which preserve fertility and avoid surgery. We systematically reviewed PubMed and Cochrane databases from January 1985 to November 2015 for evidence-based medical therapies for fibroids in the context of disease prevention, treatment of early disease, treatment of symptomatic disease, and preoperative management. We identified 2182 studies, of which 52 studies met inclusion and exclusion criteria. Published data affirm the efficacy of multiple agents, which are promising avenues for the development of medical alternatives to surgery.
Topics: Androgens; Aromatase Inhibitors; Contraceptive Agents, Female; Contraceptives, Oral, Combined; Curcumin; Delayed-Action Preparations; Drugs, Chinese Herbal; Estradiol; Estrenes; Estrogen Receptor Antagonists; Evidence-Based Medicine; Female; Fulvestrant; Gonadotropin-Releasing Hormone; Hormone Antagonists; Humans; Intrauterine Devices, Medicated; Leiomyoma; Levonorgestrel; Medroxyprogesterone Acetate; Mifepristone; Neoadjuvant Therapy; Norpregnadienes; Oximes; Plant Extracts; Receptors, Progesterone; Selective Estrogen Receptor Modulators; Tea; Uterine Myomectomy; Uterine Neoplasms; Vitamin D; Vitamins
PubMed: 26756261
DOI: 10.1097/GRF.0000000000000171 -
Issues in Law & Medicine 2015As the HIV/AIDS epidemic continues to spread in Africa and Asia, use of the injectable contraceptive steroid DMPA is widespread and has been increasing. Since studies... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
As the HIV/AIDS epidemic continues to spread in Africa and Asia, use of the injectable contraceptive steroid DMPA is widespread and has been increasing. Since studies dating back to 1992 have suggested that DMPA may increase the transmission of HIV to women, we endeavored to determine if the extant epidemiological and biological evidence is sufficient to conclude that DMPA use constitutes a definite hazard to women's health.
METHODS
We searched Medline using the search terms: contraceptives or contraception AND HIV and searched bibliographies of articles thus identified. We included in the meta-analysis all studies examining the association between use of DMPA (or injectable contraceptives comprising mostly DMPA) and the presence (cross-sectional studies, n = 8) or acquisition (longitudinal studies, n = 16) of HIV+ status in women, using a random effects models to estimate odds ratios (ORs; cross-sectional studies) and hazard ratios (HRs; longitudinal studies). Studies were excluded if the comparison group included women using any form of steroidal contraception.
RESULTS
Statistically significant positive associations between DMPA use and HIV positivity were observed both in cross-sectional (OR = 1.41, 95% CI 1.15 - 1.73) and longitudinal studies (HR = 1.49, 95% CI 1.28 - 1.73). The biological plausibility of increased vulnerability to HIV infection due to progestational action (via thinning of the vaginal epithelial barrier and immunosuppression) as well as glucocorticoid agonistic immunosuppression, are discussed.
CONCLUSION
The epidemiological and biological evidence now make a compelling case that DMPA adds significantly to the risk of male-to-female HIV transmission.
Topics: Contraceptives, Oral, Synthetic; Female; HIV Infections; Humans; Male; Medroxyprogesterone
PubMed: 26710371
DOI: No ID Found -
Breast Cancer Research and Treatment Jan 2016This systematic review summarizes research on the use of progestin and breast cancer risk. Although mainly used for contraception, progestin can help treat menstrual... (Meta-Analysis)
Meta-Analysis Review
This systematic review summarizes research on the use of progestin and breast cancer risk. Although mainly used for contraception, progestin can help treat menstrual disorders, and benign breast, uterine, and ovarian diseases. Breast cancer is the leading site of new, non-skin, cancers in females in the United States, and possible factors that may modulate breast cancer risk need to be identified. ProQuest (Ann Arbor, MI) and PubMed-Medline (US National Library of Medicine, Bethesda MD, USA) databases were used to search for epidemiologic studies from 2000 to 2015 that examined the association between progestin and breast cancer. Search terms included epidemiologic studies + progesterone or progestin or progestogen or contraceptive or contraceptive agents + breast cancer or breast neoplasms. A total of six studies were included in the review. Five of the six studies reported no association between progestin-only formulations (including norethindrone oral contraceptives, depot medroxyprogesterone acetate, injectable, levonorgestrel system users, implantable and intrauterine devices) and breast cancer risk. Duration of use was examined in a few studies with heterogeneous results. Unlike studies of other oral contraceptives, studies indicate that progestin-only formulations do not increase the risk of breast cancer, although the literature is hampered by small sample sizes. Future research is needed to corroborate these findings, as further understanding of synthetic progesterone may initiate new prescription practices or guidelines for women's health.
Topics: Breast Neoplasms; Contraceptive Agents, Female; Female; Humans; Levonorgestrel; Odds Ratio; Progestins; Risk
PubMed: 26700034
DOI: 10.1007/s10549-015-3663-1