Estrace Cream Composition
No, Estrace cream contains only estrogen (estradiol), not progesterone. This is a common point of confusion that requires clarification for safe prescribing.
What Estrace Cream Contains
- Estrace cream is a vaginal estrogen preparation containing only estradiol (17β-estradiol), with no progesterone component 1
- The cream delivers estrogen that is rapidly and efficiently absorbed into the systemic circulation through the vaginal mucosa 1
- Vaginal estrogen preparations like Estrace result in sustained high estrogen levels systemically, not just local effects 1
Clinical Implications of Estrogen-Only Formulation
When Progesterone Must Be Added
- Women with an intact uterus who use systemic estrogen (including vaginally absorbed estrogen) require progestogen therapy to prevent endometrial hyperplasia and cancer 2
- Estrogen-only therapy should only be prescribed to hysterectomized women, as there is no therapeutic advantage in prescribing progestins to women without a uterus 2
- Sequential regimens typically require 200 mg of oral or vaginal micronized progesterone for 12-14 days every 28 days when using estradiol 2
Systemic Absorption Concerns
- Vaginal estrogen creams produce significant systemic absorption, making them dangerous when estrogen is contraindicated 1
- Women with cardiovascular risk factors, high thromboembolism risk, or conditions like cyanotic heart disease should avoid estrogen-containing preparations entirely 3
- Two cases of endometrial proliferation have been documented with vaginal estrogen use, highlighting the need for progestogen protection in non-hysterectomized women 4
Common Prescribing Pitfall
- The most critical error is prescribing Estrace cream alone to women with an intact uterus without adding systemic progestogen protection 2
- While vaginal estrogens were historically considered "local only," evidence clearly demonstrates sustained systemic estrogen levels that require endometrial protection 1
- If using vaginal estradiol in women taking aromatase inhibitors (such as breast cancer patients), estriol-containing preparations may be preferable as they cannot convert to estradiol 2