Science of Hormones
Estrogen: Major sex hormone that is responsible for producing female sexual characteristics within the body. Important functions include maintaining the menstrual cycle and endowing women with female characteristics including breasts, hips, and a higher-pitched voice. The three forms of estrogen produced naturally in the body are estrone (E1), estradiol (E2), and estriol (E3).
Progesterone: Hormone with many important functions including helping the female body regulate the menstrual cycle, mature and maintain pregnancy, balance the effect of estrogen, and stimulate bone formation.
Testosterone: Major male hormone but is found in small amounts in females. In women, testosterone contributes primarily to sex drive and helps build bones.
Cortisol: Frequently referred to as the "stress hormone," cortisol is responsible for the regulation of blood pressure, inflammatory response, metabolizing glucose, and releasing insulin for blood sugar maintenance.
Thyroid: There are two thyroid hormones called Triiodothyronine (T3) and Thyroxine
(T4) which regulate the metabolism and are produced by the thyroid gland. The amount of T3 and T4 that the thyroid gland releases depends on the amount of thyroid stimulating hormone (TSH) present in the body. Thyroid hormones either circulate the blood free (unbound) or bound to transport proteins. This is why it is important during testing to measure the amount of T3 and T4 both bound and free as well as the amount of TSH in the body.