Mestranol 50microgram / Norethisterone 1mg tablets

BackgroundDeep vein thrombosis (DVT) has been reported as an adverse event for patients receiving combined oral contraceptives. Norethindrone/ethinyl estradiol (NET/EE) and drospirenone/ethinyl estradiol (DRSP/EE) are two commonly prescribed combined hormonal oral contraceptive agents used in the United States, differing in their progestin component.ObjectiveThe purpose of this study was to determine the association between the progestin component of a combined oral contraceptive and the risk of DVT in patients taking oral contraceptives for birth control using data derived from the FDA Adverse Event Reporting System (FAERS).MethodsThe risk of DVT was compared between patients that had taken NET/EE with those that had taken the DRSP/EE COC formulation for birth control. In addition, age was assessed as a possible confounder and the outcome severity for those diagnosed with DVT were compared between the two groups. Finally, association rule mining was utilized to identify possible drug-drug interactions that result in elevated DVT risk.ResultsDVT was the fourth most commonly adverse event reported for patients taking DRSP/EE accounting for 8558 cases and the seventeenth most commonly reported adverse event for NET/EE accounting for 298 cases. Age was found to be a significant confounder for users of DRSP/EE with regards to DVT risk across all age groups assessed: 2040 (ROR = 3.69, 95% CI 3.37-4.04) However, there was only a statistically significant elevated risk in patients over 40 years of age taking NET/EE (ROR = 1.98, 95% CI 1.36-2.88). Patients that had taken DRSP/EE and the corticosteroid prednisone simultaneously had an approximately 3-fold increase in DVT risk (ROR = 2.77, 95% CI 2.43-3.15) relative to individuals that had only taken DRSP/EE.ConclusionBased on this analysis, there is a higher risk of developing DVT when taking DRSP/EE than when taking NET/EE as hormonal contraception. In addition, a possibly significant drug-drug interaction between different COC formulations and prednisone were identified. This interaction may result in elevated DVT risk due to a synergistic impairment of fibrinolysis and a decrease in plasmin production.

Abstract licence: CC BY-NC-ND

Since the introduction of the first modern contraceptive methods, the interlink between bleeding control and contraceptive development has been a dominant and critical factor. This interplay has led to the development of safer and better contraceptive methods that are often used to control bleeding in both women with normal bleeding patterns as well as in those suffering from heavy menstrual bleeding (HMB). The success of progestin-only methods, such as hormonal IUDs or progestin dominant oral contraceptives in substantially decreasing and controlling menstrual bleeding, has led to development of multiple progestin-only protocols for the sole purpose of bleeding control. These include protocols designed to stop acute heavy bleeding as well as manage long-term bleeding. Recent publications describe a variety of protocols using high dose oral progestin pills with or without a medroxyprogesterone acetate (MPA) injection that demonstrate high effectiveness and good tolerability. Comparted to many other progestins, MPA is not converted in part into ethinyl estradiol and appears to have a progestin-only advantage. Norethindrone acetate (NET acetate) is converted in part to ethinyl estradiol and therefore is an especially good option for bleeding control in patients with low estrogen levels that would benefit from estrogen replacement (such as in premenopausal women with premature menopause or hypothalamic hypogonadism).

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Oral contraceptives (OCs) have been associated with long-term lower endometrial cancer risk; relatively little is known about associations with more recent OC formulations and associations with longer-term risk. A total of 107,069 women from the Nurses' Health Study II recalled OC use from age 13 to baseline (1989); biennial questionnaires updated data on OC use until 2009. OCs were classified by estrogen and progestin type, dose, and potency based on reported brand. 864 incident endometrial cancer cases were identified through 2017. Multivariable Cox proportional hazards models estimated hazard ratios (HR) and 95% confidence intervals [95% CI] for the association of OC use with endometrial cancer risk. OC use was associated with lower endometrial cancer risk (ever use, HR 0.77 [95% CI 0.65-0.91]; >10 years of use, 0.43 [0.32-0.58] vs. never OC use). Inverse associations for duration were evident regardless of time since last use. Longer durations (> 5 years) of ethinyl estradiol (0.52 [0.41-0.67]) and second-generation progestins (0.43 [0.30-0.61]), both versus never use, were more strongly associated with lower risk than mestranol (0.66 [0.50-0.88], p-het = 0.01) and first-generation progestins (0.62 [0.49-0.78], p-het = 0.03). Inverse associations were generally observed for cross-classified cumulative average estrogen and progestin dose and potency (< vs. ≥ median; ever use vs. never OC use), with the exception of high estrogen and low progestin dose. OCs were associated with lower endometrial cancer risk, independent of time since last use. Use of ethinyl estradiol and second-generation progestins were more strongly inversely associated with risk compared with older formulations.

Abstract licence: CC BY