Femhrt Should Not Be Used as a Contraceptive
Femhrt (norethindrone acetate/ethinyl estradiol) is FDA-approved exclusively for hormone replacement therapy in postmenopausal women, not for contraception, and lacks the hormonal dosing required for reliable pregnancy prevention. 1
Why Femhrt Is Not Appropriate for Contraception
Insufficient Hormonal Dosing for Contraceptive Efficacy
Femhrt contains significantly lower hormone doses than contraceptive formulations. The standard Femhrt formulation provides 1 mg norethindrone acetate with 5 mcg ethinyl estradiol, while effective combined oral contraceptives typically contain 20-35 mcg ethinyl estradiol. 2
The low-dose formulation (0.5 mg/2.5 mcg) was specifically designed to minimize estrogen exposure for menopausal symptom relief, not to suppress ovulation. This dose is approximately one-eighth the estrogen content of standard contraceptives. 3, 4
Combined hormonal contraceptives require higher estrogen doses (15-50 mcg ethinyl estradiol) to reliably prevent ovulation and achieve the typical 9% failure rate with normal use. 2
FDA-Approved Indication Is Hormone Replacement Only
The FDA label for norethindrone acetate explicitly describes its pharmacology as inducing secretory changes in an estrogen-primed endometrium, not suppressing ovulation. 1
Clinical trials of Femhrt evaluated vasomotor symptom relief, bone mineral density maintenance, and endometrial safety in postmenopausal women—not contraceptive efficacy. 3, 4
Appropriate Contraceptive Alternatives
For Women Requiring Both Contraception and Hormone Therapy
Long-acting reversible contraceptives (LARCs) including progestin or copper IUDs and progestin implants are the most effective options, with failure rates <1%. These are classified as "highly effective contraceptives" in rheumatology guidelines. 2
Standard combined oral contraceptives containing 20-35 mcg ethinyl estradiol with various progestins provide 93-97% effectiveness with typical use. 2
Progestin-only methods (pills, depot medroxyprogesterone acetate, implants, IUDs) offer effective contraception without estrogen-related stroke risk, particularly important for women over 35 or with cardiovascular risk factors. 2
Stroke Risk Considerations
Combined hormonal contraceptives with ≤20 mcg ethinyl estradiol carry mild increased stroke risk, while formulations with 30-50 mcg carry progressively higher risk. 2
The transdermal patch (releasing 20 mcg ethinyl estradiol daily with norelgestromin) and vaginal ring (releasing 15 mcg ethinyl estradiol daily with etonogestrel) both carry increased stroke risk and are classified as combined hormonal contraceptives. 2, 5
Women ≥35 years who smoke, or those with hypertension, migraine with aura, or thrombogenic conditions should avoid all estrogen-containing contraceptives. 2, 5
Clinical Pitfalls to Avoid
Do not assume that because Femhrt contains the same hormones as contraceptives, it provides contraceptive protection. The dosing is fundamentally different and designed for a different therapeutic purpose. 1, 3
Postmenopausal women using Femhrt do not require contraception, as the indication is for women who have completed menopause. However, perimenopausal women with irregular cycles still require contraception. 2
If a patient desires both contraception and menopausal symptom management, prescribe an appropriate contraceptive method separately rather than attempting to use Femhrt off-label. 2
For young women with premature ovarian insufficiency requiring hormone replacement, combined oral contraceptives may be appropriate if contraception is also needed, though hormone replacement therapy is generally preferred for bone health and symptom management. 2