Oestradiol, Prolactin, Progesterone Blood Test

Oestradiol is the strongest of the three oestrogens. It’s labelled a female hormone but it’s made in both the ovaries and testes. It’s responsible for the growth of breast tissue, the female reproductive system, and male sexual function.

In pre-menopausal women, oestradiol levels vary throughout the monthly cycle, peaking just before ovulation. Levels are lowest after menopause when the ovaries stop producing eggs. Low oestradiol levels in women can cause many symptoms associated with the menopause, including hot flushes, night sweats, and changes in mood. It can also increase the risk of osteoporosis (a condition where the bones become less dense).

In men, oestradiol levels tend to increase slightly with age as testosterone levels decline. Too much oestradiol in men can contribute to fertility problems, gynecomastia (enlarged breast tissue), and erectile dysfunction.

Progesterone is a steroid hormone produced in the corpus luteum and the adrenal glands. Its main role is to prepare the body for and support a pregnancy. It is produced in increasing amounts in the second half of the menstrual cycle. Although progesterone is considered a female hormone, men also produce progesterone in the adrenal glands and the testes. Progesterone in men plays a role in testosterone production.

Prolactin is a hormone which is produced in the pituitary gland and plays a role in reproductive health. Its primary purpose is to stimulate milk production after childbirth, and in pregnant and breastfeeding women prolactin levels can soar.