Can you be on progesterone (a hormone) therapy while still having a menstrual period?

Progesterone Therapy During Menstrual Cycles

Yes, progesterone therapy can be used while you still have menstrual periods, with specific indications and administration protocols depending on your clinical situation. 1, 2

Indications for Progesterone During Menstrual Years

• Progesterone therapy is commonly used in women who are still menstruating for various clinical conditions:
  • Secondary amenorrhea (absence of periods in women who previously had them) 2
  • Abnormal uterine bleeding due to disordered ovulation 3
  • Luteal phase deficiency 3
  • Premenstrual syndrome 3
  • Polycystic ovary syndrome 3
  • Prevention of preterm birth in high-risk pregnancies 1

Administration Protocols

For Menstrual Irregularities:

• For secondary amenorrhea: 400 mg oral progesterone daily at bedtime for 10 days 2
• This typically induces withdrawal bleeding within 7 days after completing the 10-day course in approximately 80% of women 2
• Cyclical administration is common - progesterone is given for 12-14 days every 28 days 1

For Hormone Replacement Therapy (with estrogen):

• Two main regimens when used with estrogen:
  • Cyclical regimen: Progesterone administered for 12-14 days every 28 days while estrogen is given continuously 1, 4
    • This regimen typically results in predictable withdrawal bleeding (91.9% of women) 4
  • Continuous combined regimen: Both progesterone and estrogen administered daily without interruption 1, 4
    • This regimen often results in amenorrhea (80.6% of women) 4

Routes of Administration:

• Oral: 200-400 mg daily (typically taken at bedtime) 2
• Vaginal: 45-90 mg gel or 200 mg suppository daily 1, 4
• Intramuscular: Used primarily for preterm birth prevention (17-alpha hydroxyprogesterone caproate) 1

Important Considerations

Side Effects:

• Drowsiness and dizziness are common with oral progesterone (take at bedtime) 2, 3
• Some women may experience blurred vision, difficulty speaking or walking 2
• Vaginal progesterone typically has fewer systemic side effects than oral administration 4, 3

Contraindications:

• Current or past history of certain cancers 2
• History of stroke, heart attack, or blood clots 2
• Liver problems 2
• Allergy to progesterone or its ingredients (oral progesterone contains peanut oil) 2
• Abnormal vaginal bleeding that hasn't been evaluated 2

Effect on Menstrual Cycle:

• Progesterone can affect the timing of the fertile window and menstrual cycle 5
• Higher progesterone levels in early cycle can delay the onset of the fertile window 5
• When used cyclically, progesterone withdrawal typically triggers menstrual bleeding 4

Special Considerations for Preterm Birth Prevention

• For women with singleton pregnancy and prior spontaneous preterm birth:
  • 17-alpha hydroxyprogesterone caproate 250 mg IM weekly from 16-20 weeks until 36 weeks is recommended 1
• For women with singleton pregnancy, no prior preterm birth, but short cervix (≤20 mm):
  • Vaginal progesterone 90 mg gel or 200 mg suppository daily from diagnosis until 36 weeks 1
• Not effective for multiple gestations, preterm labor, or preterm premature rupture of membranes 1

Common Pitfalls to Avoid

• Taking oral progesterone while standing can increase risk of dizziness/falls - take at bedtime with water 2
• Missing doses can lead to breakthrough bleeding or treatment failure 1
• Not recognizing that different progesterone formulations have different safety profiles (micronized progesterone has better cardiovascular and breast cancer risk profile than synthetic progestins) 3, 6
• Excessive progesterone exposure early in the menstrual cycle may negatively impact fertility 5, 7

Remember to discuss your specific situation with your healthcare provider to determine the most appropriate progesterone regimen for your condition.