Oestrone (estrone) is one of the three naturally occurring oestrogens (estrogens), the others being oestradiol (estradiol) and oestriol (estriol).

The hormone is produced primarily from androstenedione, originating from the gonads or the adrenal cortex. In premenopausal women, the ovaries secret more than 50% of oestrone. In prepubertal children, men, and non-supplemented postmenopausal women, the major portion of oestrone comes from peripheral tissue conversion of androstenedione.

Our Oestrone Blood Test is usually ordered to evaluate vaginal bleeding in postmenopausal women, which may be due to peripheral tissue conversion of androgenic steroids. This can help to guide conversations and decisions for female hormone replacement therapy.