Effect of injectable and oral contraceptives on glucose and insulin levels

Hormonal Contraception and Risk of Cardiometabolic Disease in Women with HIV

Objective: We sought to determine the association of hormonal contraception (HC) and cardiometabolic outcomes among women with human immunodeficiency virus (HIV). Methods: We included women with HIV aged 18-45 years in clinical care in the Southeastern United States between 1998 and 2018. Oral and injectable HC use was captured from medication records. Our outcomes included incident cardiovascular/thrombotic disease (CVD) (atherosclerosis, hypertension, cerebrovascular disease, thrombosis, and heart failure) and incident metabolic disorders (diabetes, dyslipidemia, obesity, and non-alcoholic steatohepatitis). We excluded women with prevalent conditions. We used multivariable marginal structural models to examine time-varying current and cumulative HC use and cardiometabolic outcomes in separate analyses, adjusting for age, race, smoking, time-varying comorbidities, CD4 cell count, HIV RNA, and antiretroviral use. Women with HC exposure were compared with women without HC exposure. Results: Among the 710 women included, 201 women (28%) used HC. CVD analyses included 603 women without prevalent CVD and 93 incident events; metabolic analyses included 365 women without prevalent metabolic disease and 150 incident events. Current and cumulative oral HC use was associated with increased odds of CVD, though this was not statistically significant (adjusted odds ratio [aOR] = 2.08, [95% confidence interval (CI): 0.80-5.43] and aOR = 1.24 [95% CI: 0.96-1.60] per year of use, respectively). Oral HC was not associated with risk of incident metabolic disorders. Depot medroxyprogesterone acetate (DMPA) was not associated with risk of incident CVD. Current and cumulative DMPA use was significantly associated with decreased odds of incident metabolic disorders (aOR = 0.48 [95% CI: 0.23, 1.00] and aOR = 0.65 [95% CI: 0.42-1.00] per year of use, respectively). Conclusion: Our results suggest that cardiovascular risk should be considered when selecting contraception for women with HIV.

High-density lipoprotein (HDL) as an indicator for alcohol use in a psychiatrically ill population

AIMS

To examine the cross sectional and longitudinal associations between the Alcohol Use Disorders Identification Test-Concise (AUDIT-C) and differences in high-density lipoprotein (HDL) in a psychiatrically ill population.

METHODS

Retrospective observational study using electronic health record data from a large healthcare system, of patients hospitalized for a mental health/substance use disorder (MH/SUD) from 1 July 2016 to 31 May 2023, who had a proximal AUDIT-C and HDL (N = 15 915) and the subset who had a repeat AUDIT-C and HDL 1 year later (N = 2915). Linear regression models examined the association between cross-sectional and longitudinal AUDIT-C scores and HDL, adjusting for demographic and clinical characteristics that affect HDL.

RESULTS

Compared with AUDIT-C score = 0, HDL was higher among patients with greater AUDIT-C severity (e.g. moderate AUDIT-C score = 8.70[7.65, 9.75] mg/dl; severe AUDIT-C score = 13.02 [12.13, 13.90] mg/dL[95% confidence interval (CI)] mg/dl). The associations between cross-sectional HDL and AUDIT-C scores were similar with and without adjusting for patient demographic and clinical characteristics. HDL levels increased for patients with mild alcohol use at baseline and moderate or severe alcohol use at follow-up (15.06[2.77, 27.69] and 19.58[2.77, 36.39] mg/dL[95%CI] increase for moderate and severe, respectively).

CONCLUSIONS

HDL levels correlate with AUDIT-C scores among patients with MH/SUD. Longitudinally, there were some (but not consistent) increases in HDL associated with increases in AUDIT-C. The increases were within range of typical year-to-year variation in HDL across the population independent of alcohol use, limiting the ability to use HDL as a longitudinal clinical indicator for alcohol use in routine care.

Fasting blood glucose, blood pressure and body mass index among combined oral contraceptive users in Chencha town Southern Ethiopia, 2019

Background

The use of contraceptives has become prevalent among women in Ethiopia. Oral contraceptive use has been suggested to trigger changes in glucose metabolism, energy expenditure, blood pressure, and body weight, among various populations and ethnic groups.

Objective

To elucidate the pattern of fasting blood glucose, blood pressure, and body mass index among combined oral contraceptive pills users compared to controls.

Methods

An institution-based cross-sectional study design was employed. A total of 110 healthy women using combined oral contraceptive pills were recruited as cases. Another 110 healthy age and sex-matched women not using any hormonal contraceptives were recruited as controls. A study was conducted between October 2018 and January 2019. Data obtained was entered and analyzed using IBM SPSS version 23 software packages. One-way ANOVA was used to identify the variation of variables in relation to the duration of use of the drug. The P-value of < 0.05 at the 95% confidence level was statistically significant.

Results

Fasting blood glucose level among oral contraceptive users (88.55 ± 7.89 mg/dl) was higher than fasting blood glucose level among oral contraceptive non-users (86.00 ± 9.85 mg/dl) with a p-value of 0.025. The mean arterial pressure of oral contraceptive users (88.2 ± 8.48 mmHg) was relatively higher than their counterparts (86.0 ± 6.74 mmHg), with a p-value of 0.04. Comparatively the body weight and body mass index among oral contraceptive users were 2.5% and 3.9% higher than non-users with a p-value of 0.03 and 0.003, respectively(5). Utilization of oral contraceptive pills for prolonged period of time seemed to be a significant predictive factor for higher mean arterial pressure and body mass index with p < 0.001and p < 0.05 respectively.

Conclusions

Use of combined oral contraceptives was associated with higher fasting blood glucose (+2.9%), mean arterial pressure (+2.5%), and body mass index (3.9%) compared to controls.

MPA alters metabolic phenotype of endometrial cancer-associated fibroblasts from obese women via IRS2 signaling

Obese women have a higher risk of developing endometrial cancer (EC) than lean women. Besides affecting EC progression, obesity also affects sensitivity of patients to treatment including medroxprogesterone acetate (MPA). Obese women have a lower response to MPA with an increased risk for tumor recurrence. While MPA inhibits the growth of normal fibroblasts, human endometrial cancer-associated fibroblasts (CAFs) were reported to be less responsive to MPA. However, it is still unknown how CAFs from obese women respond to progesterone. CAFs from the EC tissues of obese (CO) and non-obese (CN) women were established as primary cell models. MPA increased cell proliferation and downregulated stromal differentiation genes, including BMP2 in CO than in CN. Induction of IRS2 (a BMP2 regulator) mRNA expression by MPA led to activation of glucose metabolism in CO, with evidence of greater mRNA levels of GLUT6, GAPDH, PKM2, LDHA, and increased in GAPDH enzymatic activity. Concomitantly, MPA increased the mRNA expression of a fatty acid transporter, CD36 and lipid droplet formation in CO. MPA-mediated increase in glucose metabolism genes in CO was reversed with a progesterone receptor inhibitor, mifepristone (RU486), leading to a decreased proliferation. Our data suggests that PR signaling is aberrantly activated by MPA in CAFs isolated from endometrial tissues of obese women, leading to activation of IRS2 and glucose metabolism, which may lead to lower response and sensitivity to progesterone in obese women.

Exercise training improves mitochondrial respiration and is associated with an altered intramuscular phospholipid signature in women with obesity

AIMS/HYPOTHESIS

We sought to determine putative relationships among improved mitochondrial respiration, insulin sensitivity and altered skeletal muscle lipids and metabolite signature in response to combined aerobic and resistance training in women with obesity.

METHODS

This study reports a secondary analysis of a randomised controlled trial including additional measures of mitochondrial respiration, skeletal muscle lipidomics, metabolomics and protein content. Women with obesity were randomised into 12 weeks of combined aerobic and resistance exercise training (n = 20) or control (n = 15) groups. Pre- and post-intervention testing included peak oxygen consumption, whole-body insulin sensitivity (intravenous glucose tolerance test), skeletal muscle mitochondrial respiration (high-resolution respirometry), lipidomics and metabolomics (mass spectrometry) and lipid content (magnetic resonance imaging and spectroscopy). Proteins involved in glucose transport (i.e. GLUT4) and lipid turnover (i.e. sphingomyelin synthase 1 and 2) were assessed by western blotting.

RESULTS

The original randomised controlled trial showed that exercise training increased insulin sensitivity (median [IQR]; 3.4 [2.0-4.6] to 3.6 [2.4-6.2] x10^-5 pmol l^-1 min^-1), peak oxygen consumption (mean ± SD; 24.9 ± 2.4 to 27.6 ± 3.4 ml kg^-1 min^-1), and decreased body weight (84.1 ± 8.7 to 83.3 ± 9.7 kg), with an increase in weight (pre intervention, 87.8± 10.9 to post intervention 88.8 ± 11.0 kg) in the control group (interaction p < 0.05). The current study shows an increase in mitochondrial respiration and content in response to exercise training (interaction p < 0.05). The metabolite and lipid signature at baseline were significantly associated with mitochondrial respiratory capacity (p < 0.05) but were not associated with whole-body insulin sensitivity or GLUT4 protein content. Exercise training significantly altered the skeletal muscle lipid profile, increasing specific diacylglycerol(32:2) and ceramide(d18:1/24:0) levels, without changes in other intermediates or total content of diacylglycerol and ceramide. The total content of cardiolipin, phosphatidylcholine (PC) and phosphatidylethanolamine (PE) increased with exercise training with a decrease in the PC:PE ratios containing 22:5 and 20:4 fatty acids. These changes were associated with content-driven increases in mitochondrial respiration (p < 0.05), but not with the increase in whole-body insulin sensitivity or GLUT4 protein content. Exercise training increased sphingomyelin synthase 1 (p < 0.05), with no change in plasma-membrane-located sphingomyelin synthase 2.

CONCLUSIONS/INTERPRETATION

The major findings of our study were that exercise training altered specific intramuscular lipid intermediates, associated with content-driven increases in mitochondrial respiration but not whole-body insulin sensitivity. This highlights the benefits of exercise training and presents putative target pathways for preventing lipotoxicity in skeletal muscle, which is typically associated with the development of type 2 diabetes.

β-cell function in black South African women: exploratory associations with insulin clearance, visceral and ectopic fat

The role of ectopic fat, insulin secretion and clearance in the preservation ofβ-cell function in black African women with obesity who typically present with hyperinsulinaemia is not clear. We aim to examine the associations between disposition index (DI, an estimate of β-cell function), insulin secretion and clearance and ectopic fat deposition. This is a cross-sectional study of 43 black South African women (age 20-35 years) with obesity (BMI 30-40 kg/m2) and without type 2 diabetes that measured the following: DI, insulin sensitivity (SI), acute insulin response (AIRg), insulin secretion rate (ISR), hepatic insulin extraction and peripheral insulin clearance (frequently sampled i.v. glucose tolerance test); pancreatic and hepatic fat, visceral adipose tissue (VAT) and abdominal s.c. adipose tissue (aSAT) volume (MRI), intra-myocellular (IMCL) and extra-myocellular fat content (EMCL) (magnetic resonance spectroscopy). DI correlated positively with peripheral insulin clearance (β 55.80, P = 0.002). Higher DI was associated with lower VAT, pancreatic fat and soleus fat, but VAT explained most of the variance in DI (32%). Additionally, higher first phase ISR (P = 0.033) and lower hepatic insulin extraction (P = 0.022) were associated with lower VAT, independent from SI, rather than with ectopic fat. In conclusion, peripheral insulin clearance emerged as an important correlate of DI. However, VAT was the main determinant of a lower DI above ectopic fat depots. Importantly, VAT, but not ectopic fat, is associated with both lower insulin secretion and higher hepatic insulin extraction. Prevention of VAT accumulation in young black African women should, therefore, be an important target for beta cell preservation.

Hyperinsulinemic-euglycemic clamp over the first year of use of depot-medroxyprogesterone acetate as a contraceptive

OBJECTIVE

The literature lacks data on the use of the gold-standard hyperinsulinemic-euglycemic clamp (HEC) technique for the evaluation of insulin resistance (IR) in depot-medroxyprogesterone acetate (DMPA) users. This study assessed carbohydrate metabolism in non-obese users of DMPA using the HEC technique.

STUDY DESIGN

A prospective, non-randomized, comparative study conducted at the Family Planning Clinic/Metabolic Unit, University of Campinas, Brazil. Forty-eight women aged 18-39 years underwent HEC: 30 initiating use of DMPA and 18 initiating use of a copper intrauterine device (IUD). Data from 15 women in each group, who completed the follow-up and underwent HEC at12 months, were compared using repeated measures ANOVA. All women were advised to perform aerobic physical exercise for 150 min/week; body composition and total energy intake were evaluated. Main outcome measures were IR defined by M-value <4 mg/kg/min, and blood levels of insulin. Additional outcomes were total cholesterol, HDL-cholesterol, triglycerides, LDL-cholesterol, adipokines and free fatty acids.

RESULTS

At 12 months, two women in the DMPA group and none in the IUD group had developed IR. The groups were similar in in M-values and in blood levels of insulin, total cholesterol, HDL-cholesterol, LDL-cholesterol, adipokines or free fatty acids. Triglyceride levels increased in the DMPA group when compared to the IUD group, 80.0 (SD 47.8) versus 61.8 (SD 35.8) mg/dL respectively, (p=.033); and increased the total daily energy intake, 1828.3 (SD 518.9) versus 1300.8 (SD 403.4) kilocalories/24hs, respectively in the same groups, (p=.041). All the DMPA users showing higher insulin sensitivity at 12 months reported performing physical activity regularly.

CONCLUSIONS

Changes occurred in carbohydrate metabolism in DMPA users in the first year of use of the method. It is possible that the regular aerobic exercise may exert a beneficial and protective effect against the factors that trigger these changes.

IMPLICATIONS STATEMENT

Carbohydrate metabolism undergoes adverse changes in few young non-obese women during the first year of DMPA use and regular aerobic exercise may exert a beneficial and protective effect against these changes.

The Deterioration of the Glycemic Profile during Hormone Replacement Therapy in a Patient with Fulminant Type 1 Diabetes

Although most women with type 1 diabetes experience the normal transition to menopause, there is little information about the impact of hormone replacement therapy on their glycemic profiles. A 54-year-old postmenopausal woman with fulminant type 1 diabetes was admitted to our hospital due to diabetic ketoacidosis. She was treated with fluid replacement and a continuous insulin infusion. Thereafter, her glycemic profile was well maintained by daily multiple insulin injections. However, her glycemic profiles immediately deteriorated following the administration of progesterone in hormone replacement therapy. This transient deterioration implies that external progesterone can lead to the deterioration of glycemic profiles in postmenopausal women with type 1 diabetes.

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.

Current Therapies for the Medical Management of Diabetes

Diabetes affects a large and diverse number of individuals who share in common its risks for complications but who differ greatly from one another in age, health, and a number of circumstances influential to successful treatment. Because type 2 diabetes comprises the majority of diabetes cases, a number of agents have been developed for its treatment. Their unique properties offer opportunities to overcome some of the treatment limitations of older medicines and enable a more individualized and flexible approach to glucose-lowering. At the same time, new medications are accompanied by greater costs and uncertainties about their long-term benefits or safety, and thus the present state of care for type 2 diabetes places focus on a process of shared decision-making between the clinician and patient as to which treatments can optimize health while minimizing harms. We review the major classes of diabetes agents and provide some guidance for how one might approach decision-making in choosing among them.

Epigenome-wide DNA methylation analysis implicates neuronal and inflammatory signaling pathways in adult murine hepatic tumorigenesis following perinatal exposure to bisphenol A

Developmental exposure to the endocrine-active compound bisphenol A (BPA) has been linked to epigenotoxic and potential carcinogenic effects in rodent liver, prostate, and mammary glands. A dose-dependent increase in hepatic tumors in 10-month mice perinatally exposed to one of three doses of BPA (50 ng, 50 µg, or 50 mg BPA/kg chow) was previously reported. These tumors represent early-onset disease and lack classical sexual dimorphism in incidence. Here, adult epigenome-wide liver DNA methylation profiles to identify gene promoters associated with perinatal BPA exposure and disease in 10-month mice with and without liver tumors were investigated. Mice with hepatic tumors showed 12,822 (1.8%) probes with differential methylation as compared with non-tumor animals, of which 8,656 (67.5%) were hypomethylated. A significant enrichment of differential methylation in Gene Ontology (GO) terms and biological processes related to morphogenesis and development, and epigenomic alteration were observed. Pathway enrichment revealed a predominance of hypermethylated neuronal signaling pathways linked to energy regulation and metabolic function, supporting metabolic consequences in the liver via BPA-induced disruption of neuronal signaling pathways. Hypothesis-driven pathway analysis revealed mouse and human genes linked to BPA exposure related to intracellular Jak/STAT and MAPK signaling pathways. Taken together, these findings are indicators of the relevance of the hepatic tumor phenotype seen in BPA-exposed mice to human health. This work demonstrated that epigenome-wide discovery experiments in animal models were effective tools for identification and understanding of paralagous epimutations salient to human disease. Environ. Mol. Mutagen. 57:435-446, 2016. © 2016 Wiley Periodicals, Inc.

Associations between body fat distribution, insulin resistance and dyslipidaemia in black and white South African women

Aim

The aim was to examine differences in body fat distribution between premenopausal black and white South African (SA) women and explore the ethnic-specific associations with cardiometabolic risk.

Methods

Body composition, using dual-energy X-ray absorptiometry (DXA) and computerised tomography, insulin resistance (HOMA-IR) and lipid levels were assessed in 288 black and 197 white premenopausal SA women.

Results:

Compared to the white women, black women had less central and more peripheral (lower-body) fat, and lower serum lipid and glucose concentrations, but similar homeostasis models for insulin resistance (HOMA-IR) values. The associations between body fat distribution and HOMA-IR, triglyceride and high-density lipoprotein cholesterol concentrations were similar, while the associations with fasting glucose, total and low-density lipoprotein cholesterol levels differed between black and white women.

Conclusion:

Ethnic differences in body fat distribution are associated, in part, with differences in cardiometabolic risk between black and white SA women.

Long-Term Clinical Outcomes in Diabetic Rhesus Macaques (Macaca mulatta) Treated with Medroxyprogesterone Acetate for Endometriosis

Depot medroxyprogesterone acetate (DMPA) is a common medical treatment for endometriosis in NHP. Because DMPA reportedly impairs glucoregulatory function in humans and rhesus macaques, as well as predisposes humans to diabetes mellitus (DM), we performed a retrospective study to further investigate its potential long-term clinical effects in animals with and without DM. Using a cohort of 29 rhesus macaques, we explored the hypotheses that DMPA treatment accelerates the onset of DM and that its use in rhesus macaques with endometriosis worsens clinical outcome measures (lifespan, body weight and body condition score). For both body weight and body condition score, a declining and statistically significant trend in mean values was evident as macaques developed either DM, or endometriosis or both. The addition of DMPA did not significantly alter this pattern. The presence of DM, endometriosis, or DMPA treatment statistically but not clinically significantly increased risk of death. Similarly, the presence of the 2 highly correlated variables endometriosis and DMPA treatment statistically but not clinically significantly increased the risk of incident DM. These results indicate that DMPA treatment was associated with worsening trends in lifespan and incident DM, however these trends did not achieve clinical significance in this cohort.

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.

Effect of hormonal contraceptives on vitamin B12 level and the association of the latter with bone mineral density

BACKGROUND

The study was conducted to estimate the effect of depot medroxyprogesterone acetate (DMPA) and oral contraceptives (OC) containing 20 mcg ethinyl estradiol on serum B12 and whether observed changes impact bone mineral density (BMD).

STUDY DESIGN

Serum B12 and BMD at the lumbar spine and femoral neck were measured on 703 women using OC, DMPA or nonhormonal (NH) birth control at baseline and every 6 months thereafter for 3 years.

RESULTS

OC and DMPA users experienced greater decreases in B12 than NH users (p<.001). A sharp decrease in B12 was observed during the first 6 months of hormonal contraceptive use (OC: 97 pg/mL and DMPA: 64 pg/mL) in contrast to 14 pg/mL among NH users (20%, 13% and 3% of their baseline values, respectively). Over the following 30 months, B12 levels of OC users remained almost flat, while DMPA users had a further 22-unit decrease. Very few women demonstrated B12 deficiency. Moreover, B12 levels were not associated with BMD.

CONCLUSION

Hormonal contraception causes B12 levels to decrease, but this does not appear to be clinically significant or affect BMD.