Oestrogen is a class of female sex hormone that is produced in the ovaries and to some extent the testes.
Oestrogen is divided into several different types – oestrone, oestradiol and oestriol. Together they stimulate ovulation (the release of an egg from an ovary once a month) and the development of breasts, pubic hair and other sexual characteristics at puberty in women. The amount present in urine can be measured in the investigation of female infertility, determination of menopause state and even sex determination, but blood measurements of a specific form of oestrogen, oestradiol, are more accurate. In urine the normal results in µg/24 hours are:
|Oestrogen||Male||Menstruating woman||After menopause|
|Oestrone||0 to 5||5 to 20||0.3 to 2.4|
|Oestradiol||0 to 5||2 to 10||0 to 1.4|
|Oestriol||0 to 10||5 to 30||2.2 to 7.5|
A high level in females usually indicates sex hormone therapy, while in males it may be due to feminisation from taking female hormones or abnormal hormone production within body. A low level in women indicates infertility or menopause.
As a medication oestrogen has the common trade name Premarin, which is derived from the original rather unsavoury source of oestrogen, pregnant mare’s urine. It is used as a tablet, vaginal cream or injection for hormone replacement therapy in the menopause.
It should not be used in pregnancy, breastfeeding, children or males, but accidental usage in these situations is unlikely to be harmful. Use oestriol with caution in epilepsy, migraine, heart failure, high blood pressure, kidney disease, diabetes, porphyria or uterine disease, and not at all if suffering from liver disease, breast or genital cancer, blood clots, undiagnosed vaginal bleeding, endometriosis, porphyria or otosclerosis.
Side effects may include abnormal uterine bleeding, vaginal thrush, nausea, fluid retention, weight gain, breast tenderness. Unusual effects may include a rash, blurred vision, vomiting, bloating, intestinal cramps, pigmentation of skin on face. Severe but rare reactions may be blood clots, calf or chest pain and yellow skin (jaundice). Smoking increases the risk of serious side effects.
It may interact with other sex hormones, rifampicin and the herbs saw palmetto, alfalfa, dong quai, ginseng, liquorice, red clover. Vomiting and abnormal vaginal bleeding are the only likely effects of an overdose.