A hormone that promotes the development and maintenance of female sex characteristics.

GoldBamboo

... Why get tested?
To measure or monitor your estrogen levels if you are a woman who has unexplained abnormal menstrual cycles, abnormal or heavy bleeding, infertility problems, symptoms of menopause, or any other hormonal alterations; also used to test for fetal-placental competence during early stages of pregnancy; the presence of female-like characteristics in males may require hormone level evaluations as well

When to get tested?
When your doctor thinks that you have symptoms of a hormone imbalance, abnormal vaginal bleeding, unusual and/or early sex organ development (male and female), or when your doctor wants to monitor the health of your placenta and fetus during pregnancy

Sample required?
A blood sample drawn from a vein in your arm, a 24-hour urine sample, or (in some cases) a fresh saliva sample
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Lab Tests Online - more...

Estrogens (also oestrogens) are a group of steroid compounds, named for thei ...
Wikipedia - [full article]

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