Combined hormonal contraceptives (CHCs) place women at increased risk of venous thromboembolic events (VTEs) and arterial thrombotic events (ATEs), including acute myocardial infarction and ischemic stroke. There is concern that three recent CHC preparations [drospirenone-containing pills (DRSPs), the norelgestromin-containing transdermal patch (NGMN) and the etonogestrel vaginal ring (ETON)] may place women at even higher risk of thrombosis than other older low-dose CHCs with a known safety profile.
Study Design
All VTEs and all hospitalized ATEs were identified in women, ages 10-55 years, from two integrated health care programs and two state Medicaid programs during the time period covering their new use of DRSP, NGMN, ETON or one of four low-dose estrogen comparator CHCs. The relative risk of thrombotic and thromboembolic outcomes associated with the newer CHCs in relation to the comparators was assessed with Cox proportional hazards regression models adjusting for age, site and year of entry into the study.
Results
The hazards ratio for DRSP in relation to low-dose estrogen comparators among new users was 1.77 (95% confidence interval 1.33-2.35) for VTE and 2.01 (1.06-3.81) for ATE. The increased risk of DRSP was limited to the 10-34-year age group for VTE and the 35-55-year group for ATE. Use of the NGMN patch and ETON vaginal ring was not associated with increased risk of either thromboembolic or thrombotic outcomes.
Conclusions
In new users, DRSP was associated with higher risk of thrombotic events (VTE and ATE) relative to low-dose estrogen comparator CHCs, while the use of the NGMN patch and ETON vaginal ring was not.
drospirenone venous thromboembolism risk combined hormonal contraceptives, combined hormonal contraceptives arterial thrombotic events new users, transdermal patch vaginal ring thromboembolism risk comparison, drospirenone pill VTE ATE risk Cox proportional hazards, hormonal contraceptive cardiovascular risk age stratification, norelgestromin patch etonogestrel ring safety thrombosis, oral contraceptive drospirenone vs low dose estrogen comparator VTE, new user combined hormonal contraceptive thrombotic risk cohort study, hormonal contraception acute myocardial infarction ischemic stroke risk, Sidney Cheetham contraceptive thromboembolism cardiovascular events
PMID 23083525 23083525 DOI 10.1016/j.contraception.2012.09.015 10.1016/j.contraception.2012.09.015
Cite this article
Sidney, S., Cheetham, T. C., Connell, F. A., Ouellet-Hellstrom, R., Graham, D. J., Davis, D., Sorel, M., Quesenberry, C. P., & Cooper, W. O. (2013). Recent combined hormonal contraceptives (CHCs) and the risk of thromboembolism and other cardiovascular events in new users. Contraception, 87(1), 93-100. https://doi.org/10.1016/j.contraception.2012.09.015
Sidney S, Cheetham TC, Connell FA, Ouellet-Hellstrom R, Graham DJ, Davis D, et al. Recent combined hormonal contraceptives (CHCs) and the risk of thromboembolism and other cardiovascular events in new users. Contraception. 2013;87(1):93-100. doi:10.1016/j.contraception.2012.09.015
Sidney, Stephen, et al. "Recent combined hormonal contraceptives (CHCs) and the risk of thromboembolism and other cardiovascular events in new users." Contraception, vol. 87, no. 1, 2013, pp. 93-100.
The combined hormonal contraceptive (CHC) with ethinylestradiol and progestins is the most widely used contraceptive method among young women and is used by millions worldwide. However, uncertainties exist about the risk of ischemic stroke associated with the use of CHCs with low-dose ethinylestradiol (<50-µg ethinylestradiol) and with the newest fourth-generation progestins that have only been sparsely investigated for the risk of ischemic stroke. In this cohort study based on Danish registries covering the entire Danish female population aged 18 to 49 years from 2004 to 2021, we investigated incidence rate ratios (IRRs) of ischemic stroke using CHCs compared with nonuse of hormonal contraceptives. Analyses focused on comparing CHCs based on ethinylestradiol content (30-40versus ≤20-μg ethinylestradiol), progestin generation (second, third, and fourth) in CHCs, and route of administration (monophasic versus sequential). Poisson regression models adjusting for age, education, ethnicity, calendar year, and medication used for risk factors were utilized. In total, 1 711 757 nonpregnant women contributed 14 697 788 person-years to the investigation. For users of CHCs containing <50-µg ethinylestradiol, the adjusted IRR was increased by 1.77 (95% CI, 1.62-1.93) compared with nonusers of hormonal contraceptives. IRR did not differ between CHCs with 30to 40and ≤20-µg ethinylestradiol. Adjusted incidence rate difference between CHC users and nonusers of hormonal contraceptives ranged from 1 in 100 000 women per year in 18 to 24 years of age to 24 in 100 000 women per year in ≥45 years of age. Incidence rate in users of fourth-generation CHCs was 30% lower than that of second-generation CHCs adjusted IRR (0.70 [95% CI, 0.50-0.98]). IRR for users of third-generation CHCs did not differ significantly from that of second-generation users adjusted IRR (1.14 [95% CI, 0.97-1.35]). Use of CHCs was associated with a 1.77 higher IRR of ischemic stroke. IRR did not relate to ethinylestradiol content in users of CHCs with <50-µg ethinylestradiol. IRR was 30% lower in users of fourth-generation than in users of second-generation CHCs.
Contraception/ComparisonAdverse EventsCopper vs HormonalDevice Complications
To examine trends in national reporting of broken intrauterine devices (IUDs). We enumerated IUD device "breakage" reports in the Food and Drug Administration Adverse Event Reporting System from inception (1998) until February 2022. We explored associations of breakage with IUD type (copper versus hormonal), year reported, reporter (consumer versus clinician), and patient characteristics (age and weight). We identified 4144 breakage reports for copper versus 2140 for hormonal IUDs. Among the 170,215 adverse events reported, breaks were disproportionately reported for copper (9.6%) versus hormonal (1.7%) IUDs. National pharmacovigilance data suggests disproportionate breakage in copper versus hormonal IUDs though the true prevalence of breaks cannot be calculated from this dataset.
Contraception/ComparisonEfficacyNovel FormulationsPooled Analysis
Open Access
To evaluate overall and subgroup efficacy of an estetrol (E4) 15 mg drospirenone (DRSP) 3 mg oral contraceptive in a 24/4-day regimen. We pooled efficacy outcomes from 2 pivotal phase 3 contraceptive trials with E4/DRSP conducted in the United States/Canada and Europe/Russia. We assessed Pearl Index (PI; pregnancies per 100 participant-years) and 13-cycle life-table pregnancy rates in at-risk cycles (confirmed intercourse and no other contraceptive use) among participants 16 to 35 years. We calculated PI by age and further subcategorization (contraceptive history and body mass index [BMI]). We performed multivariable analysis using Cox regression to assess impact of potential confounding factors. Analyses included 3027 participants, of whom 451 (14.9%) had a BMI ≥30 kg/m(2). The pooled PI was 1.52 (95% confidence interval 1.04-2.16) and the 13-cycle life-table pregnancy rate was 1.28% (0.83%-1.73%). We calculated unadjusted pooled PI in participants 16 to 25 years and 26 to 35 years of 1.61 (0.94-2.57) and 1.43 (0.78-2.40), respectively; in new starters and switchers of 1.88 (1.09-3.00) and 1.24 (0.68-2.08), respectively; and by BMI <25 kg/m(2), 25 to 29.9 kg/m(2), and ≥30 kg/m(2) of 1.14 (0.64-1.88), 2.19 (1.05-4.03), and 2.27 (0.83-4.94), respectively. In multivariable analysis, we found associations of prior pregnancy (hazard ratio [HR] 3.61[1.56-8.38]), Black race (HR 4.61[1.97-10.80]), age 16 to 25 years (HR 2.37[1.09-5.15]) and compliance <99% of expected pills (HR 4.21[2.04-8.66]) with conception. E4/DRSP is an effective oral contraceptive overall and across subgroups stratified by age, contraceptive history, and BMI. Other than compliance, predictors of contraceptive failure are nonmodifiable. Pooled results from two phase 3 trials demonstrate high contraceptive efficacy of the novel estetrol-drospirenone oral contraceptive. Several non-modifiable risk factors, including prior pregnancy, race, and age, are associated with higher pregnancy risk. Additional research is needed to better understand predictors of combined oral contraceptive failure.
Fertility AwarenessApp ComparisonFertile Window IdentificationBBT and Cervical Mucus
The Natural Cycles app employs daily basal body temperature to define the fertile window via a proprietary algorithm and is clinically established effective in preventing pregnancy. We sought to (1) compare the app-defined fertile window of Natural Cycles to that of CycleProGo, an app that uses BBT and cervical mucus to define the fertile window and (2) compare the app-defined fertile windows to the estimated physiologic fertile window. Daily BBT were entered into Natural Cycles from 20 randomly selected regularly cycling women with at least 12 complete cycles from the CycleProGo database. The proportion of cycles with equivalent (±1 cycle day) fertile-window starts and fertile-window ends was determined. The app-defined fertile windows were then compared to the estimated physiologic fertile window using Peak mucus to estimate ovulation. Fifty seven percent of cycles (136/238) had equivalent fertile-window starts and 36% (72/181) had equivalent fertile-window end days. The mean overall fertile-window length from Natural Cycles was 12.8 days compared to 15.1 days for CycleProGo (p < 0.001). The Natural Cycles algorithm declared 12% to 30% of cycles with a fertile-window start and 13% to 38% of cycles with a fertile-window end within the estimated physiologic fertile window. The CycleProGo algorithm declared 4% to 14% of cycles with a fertile-window start and no cycles with a fertile-window end within the estimated physiologic fertile window. Natural Cycles designated a higher proportion of cycles days as infertile within the estimated physiologic fertile window than CycleProGo.
Use of cervical mucus in addition to BBT may improve the accuracy of identifying the fertile window. Additional studies with other markers of ovulation and the fertile window would give additional insight into the clinical implications of app-defined fertile window differences.