Detailed definition
Estring is an estradiol-releasing silicone ring designed for treatment of genitourinary syndrome of menopause. It releases approximately 7.5 mcg of estradiol per day at a relatively constant rate over 90 days. The ring is inserted into the upper vagina by the patient (or clinician) and removed and replaced every 3 months. Serum estradiol elevation is minimal at this delivery rate. A separate higher-dose ring, Femring, delivers systemic doses (0.05 or 0.1 mg/day estradiol) and is FDA-approved for vasomotor symptoms — Femring is a systemic HRT option, not a local-only preparation, and requires progesterone for women with a uterus.
Why it matters in menopause
Estring is the most "set-it-and-forget-it" vaginal estrogen option. For women who dislike daily application or weekly tablets, the 90-day ring is a low-effort, well-tolerated solution.
Related terms
Sources
External references: Wikipedia.