Last reviewed 2026-04-22 · How we verify

norelgestromin + ethinyl estradiol

Norelgestromin and ethinyl estradiol work together as a hormonal contraceptive by suppressing ovulation through inhibition of gonadotropin-releasing hormone (GnRH) and feedback inhibition of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).

Norelgestromin and ethinyl estradiol work together as a hormonal contraceptive by suppressing ovulation through inhibition of gonadotropin-releasing hormone (GnRH) and feedback inhibition of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Used for Contraception (prevention of pregnancy), Regulation of menstrual cycle.

At a glance

Mechanism of action

Norelgestromin is a progestin that provides contraceptive efficacy primarily through cervical mucus thickening and endometrial atrophy, while ethinyl estradiol is an estrogen that enhances ovulation suppression and stabilizes the endometrium. Together, they prevent the LH surge necessary for ovulation and create an unfavorable environment for sperm transport and implantation.

Approved indications

• Contraception (prevention of pregnancy)
• Regulation of menstrual cycle

Common side effects

• Nausea
• Headache
• Breast tenderness
• Breakthrough bleeding
• Mood changes
• Venous thromboembolism
• Hypertension

Key clinical trials

• Transdermal Ethinyl Estradiol and Norelgestromin for Irregular Bleeding in Contraceptive Implant Users (PHASE2)
• Study of the Safety and Efficacy of MR-100A-01 in Approximately 1200 Healthy Women for up to 13 Cycles (PHASE3)
• Inpatient Adolescent Contraception (EARLY_PHASE1)
• A Trial in Healthy Female Subjects to Compare the Pharmacokinetics of Ethinyl Estradiol of NuvaRing®, a Contraceptive Patch (EVRA(TM)) and an Oral Contraceptive (Microgynon® 30) (Study 34237 (P06650)) (COMPLETED) (PHASE4)
• Effects of Oral vs. Non-oral Contraceptives on the GH/IGF-1 Axis (PHASE4)
• A Postmarketing Study of the Risk of Venous Thromboembolism (Blood Clots), Myocardial Infarction (Heart Attacks), and Stroke Among Women Using ORTHO EVRA (Norelgestromin and Ethinyl Estradiol Contraceptive Patch) Compared With Women Who Take Oral Contraceptives for Birth Control
• Postmarketing Study of ORTHO EVRA (Norelgestromin and Ethinyl Estradiol Contraceptive Patch) in Relation to Venous Thromboembolism (Blood Clots), Stroke and Heart Attacks
• Relative Risks for Non-fatal Venous Thromboembolism, Ischemic Stroke and Myocardial Infarction in Users of ORTHO EVRA(Norelgestromin and Ethinyl Estradiol Contraceptive Patch) Compared to Levonorgestrel-containing Oral Contraceptives.

Primary sources

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