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New Contraception Update - Annovera, Phexxi, Slynd, and Twirla
Courtney C Baker1, Melissa J Chen1
1Department of Obstetrics and Gynecology, University of California, Davis, 4860 Y Street, Suite 2500, Sacramento, CA 95817, USA.
Purpose Of Review:
In this review, we discuss the efficacy, safety, and benefits of four new contraceptive products available in the USA, specifically Annovera, Phexxi, Slynd, and Twirla.
Recent Findings:
Annovera is a vaginal ring releasing ethinyl estradiol and segesterone acetate that can be used for up to one year (13 cycles), offering patients an effective, user-controlled option that may improve contraceptive access for those in low-resource settings or those with barriers to retrieving monthly prescriptions; however, given limited efficacy and safety data in people with body mass index (BMI) > 29 kg/m2, clinicians may consider whether Annovera is an appropriate contraceptive method for obese patients if there are other acceptable alternatives. Phexxi prescription-only vaginal gel is a user-controlled, non-hormonal, on-demand contraceptive method that represents a novel addition to the market with its additional uses as a personal lubricant and as a potential microbicide for urogenital infection prevention. Slynd, a drospirenone-only pill, provides more flexibility for delayed or missed pills while maintaining efficacy and a more favorable bleeding profile compared with previously available progestin-only pills. Lastly, Twirla is a transdermal patch releasing ethinyl estradiol and levonorgestrel that offers users an additional option for a user-controlled, combined hormonal contraceptive method without daily dosing; however, prescription is limited to patients with BMI < 30 kg/m2 due to decreased efficacy and VTE events in people with obesity.
Summary:
The addition of these products expands the available options for pregnancy prevention to address unmet contraceptive needs.
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