Taking Additional Norethindrone with Lo Loestrin Fe
Adding one pill of norethindrone to Lo Loestrin Fe is safe and may be appropriate for specific clinical indications, including extended cycle contraception, endometrial protection, or management of breakthrough bleeding, but the rationale for this addition should be clarified with your provider.
Understanding the Combination
Lo Loestrin Fe contains norethindrone acetate 1 mg and ethinyl estradiol 20 mcg for 21 days, followed by placebo pills 1. Adding a separate norethindrone pill creates a higher total progestin dose or extends the active hormone phase.
Potential Clinical Rationales
Extended or Continuous Cycling:
- Seven consecutive days of active hormonal pills are necessary to reliably prevent ovulation 2
- Skipping the placebo week and continuing with active pills maintains continuous ovarian suppression and potentially improves contraceptive effectiveness 2
- Extended cycles benefit conditions including severe dysmenorrhea, endometriosis, heavy menstrual bleeding, migraine, and acne 2
- The most common adverse effect is unscheduled breakthrough bleeding, which typically improves over time 2
Endometrial Protection:
- The minimum effective dose of norethindrone for endometrial protection with estrogen is 1 mg daily, taken continuously without interruption 3
- This dose effectively prevents endometrial hyperplasia while minimizing side effects 3
- Continuous combined regimens require at least 1 mg of norethindrone daily when administered with estradiol 3
Breakthrough Bleeding Management:
- Lo Loestrin Fe (norethindrone acetate 1 mg/ethinyl estradiol 20 mcg) has higher rates of breakthrough bleeding compared to other formulations 4, 5
- Studies show breakthrough bleeding rates of 23.5-49.7% with this formulation 6
- Extending active hormone days from 21 to 24 significantly reduces intracyclic bleeding days (0.95 vs 1.63 days; p=0.005) 5
Safety Considerations
Contraindications remain unchanged:
- Active or history of thromboembolic disease, stroke, or myocardial infarction 1
- Breast cancer, undiagnosed genital bleeding, hepatic disease, or pregnancy 1
- Migraine headaches with focal neurologic symptoms 7
Monitoring requirements:
- Blood pressure must be checked at baseline and regularly during treatment 7
- Pregnancy status must be confirmed negative before any regimen change 7, 3
- Review all medications for interactions, particularly antibiotics, anticonvulsants, HIV protease inhibitors, and St. John's wort 1, 7
Cardiovascular risk increases:
- Women ≥35 years have substantially increased stroke risk, particularly if they smoke 7
- Risk increases after 1 year of use and continues to rise with each additional 5 years 7
- Bile acid sequestrants may decrease absorption of oral contraceptives containing ethinyl estradiol and norethindrone; give contraceptives 4 hours before bile acid sequestrants 1
Common Pitfalls to Avoid
Do not confuse norethindrone with norethindrone acetate - norethindrone acetate requires lower doses due to higher potency 3. If your provider prescribed norethindrone (not norethindrone acetate), the dosing differs.
Timing matters for contraceptive efficacy - if adding norethindrone to extend cycles, start the additional pill immediately after finishing the 21 active pills without taking the hormone-free interval 2. If missed pills occur in the last week when planning to skip the placebo week, proceed directly to the next pack 2.
Breakthrough bleeding is expected initially - this typically improves over 2-3 cycles and does not indicate contraceptive failure 2, 5.
What to Clarify with Your Provider
Ask specifically whether the additional norethindrone is intended for:
- Extending your contraceptive cycle continuously (skipping withdrawal bleeds)
- Managing breakthrough bleeding or spotting
- Treating a specific gynecologic condition (endometriosis, dysmenorrhea, heavy bleeding)
- Providing additional endometrial protection
The answer determines the exact timing and duration of the additional pill 3, 2, 8.