From the Guidelines
Progesterone is prescribed in patients using only topical estrogen to decrease the risk of endometrial cancer. The addition of progesterone to estrogen replacement therapy is crucial to counterbalance the estrogenic stimulation of the endometrium, thereby reducing the likelihood of endometrial proliferation and potential malignant transformation 1.
- The specific progesterone regimen may vary depending on individual patient factors, including menopausal status and uterine integrity.
- For women at high risk for endometrial cancer, such as those with Lynch syndrome, additional monitoring measures like transvaginal ultrasound and annual endometrial biopsies may be suggested 1.
- The recommended progesterone regimen typically involves micronized progesterone 100-200mg orally for 10-14 days per month, although this may be adjusted based on patient-specific factors.
- The use of progesterone in conjunction with topical estrogen therapy is supported by evidence from studies on gynecologic cancers and solid organ transplantation, which highlight the importance of progestogenic opposition in mitigating the risk of endometrial cancer 1.
From the FDA Drug Label
When estrogen is prescribed for a postmenopausal woman with a uterus, a progestin should also be initiated to reduce the risk of endometrial cancer. The patient is prescribed progesterone because they are using estrogen replacement therapy and have a uterus, to reduce the risk of endometrial cancer 2.
- The use of estrogen alone in women with a uterus increases the risk of endometrial cancer.
- Progesterone is added to estrogen replacement therapy to mitigate this risk.