Definition: Amenorrhea means the absence of menstrual periods. MedlinePlus splits it in two. Primary amenorrhea is when a girl older than 15 who has gone through other puberty changes has not started her periods. Secondary amenorrhea is when someone who had normal cycles stops having periods for 6 months or longer.
MedlinePlus says the most common cause of secondary amenorrhea is pregnancy, and breastfeeding and menopause are common natural causes. Others include heavy exercise, low body fat, sudden weight loss, stress, thyroid problems, pituitary tumors, PCOS and hormone shots. Tests usually include a pregnancy test and hormone levels such as estradiol, FSH, LH, prolactin and TSH.
| Label | What it says |
|---|---|
| Provera and Prometrium | Approved to treat secondary amenorrhea. In Prometrium studies, withdrawal bleeding came within 7 days of the last dose in 80% vs 10% on placebo. |
| Depo-Provera | No periods in 55% of women at 12 months and 68% at 24 months. |
| Lupron Depot 3.75 mg | Periods stopped in 74% after the first month and 98% after the second; cycles returned in 95% by 3 months after treatment. |
On some labels it is a use; on others it is an expected effect.
Because the definition counts months without a period, the date of the last one is the key number. Period dates kept next to hormone shots or progestin courses show whether a missed period lines up with a medicine.
Read more on Dose Track: Provera side effects · Prometrium side effects · Depo-Provera side effects · Provera vs Prometrium