Estrogen is one of the 2 main sex hormones produced in a woman's body. Estrogen is produced primarily by the ovaries, but also in smaller amounts by the adrenal glands and fat tissue. It is responsible for the physical changes that occur during puberty such as breast growth and the start of the menstrual cycle. Estrogen helps regulate the menstrual cycle and levels of this hormone fluctuate throughout the month. Levels are highest during ovulation and lowest during your period. Estrogen also helps with many other systems and functions throughout the body including cholesterol levels and bone health.

Function: Regulates menstrual period and many bodily functions.

Deficiency: Deficiency can cause irregular menstrual cycles, trouble sleeping, hot flashes, vaginal dryness (symptoms seen in menopause).

Excess: Excess estrogen can cause weight gain, more severe PMS, fibroids, fatigue.

Timing: Peaks at ovulation, lowest point on the first day of your cycle.



Progesterone is a hormone produced primarily by the corpus luteum in the ovary after ovulation, but also in small amounts by the adrenal gland. It is also produced by the placenta during pregnancy, and plays a major role in maintaining a healthy pregnancy. After ovulation occurs the corpus luteum in the ovary produces progesterone to stimulate the lining of the uterus to prepare for a fertilized egg. If implantation does not occur, the corpus luteum breaks down, progesterone levels drop and the lining will be shed. If implantation does occur, once the placenta is formed it will begin producing progesterone and will continue throughout the pregnancy. Progesterone during pregnancy has many roles including fetal development, stimulating growth of breast tissue, and preventing ovulation.

Function: Prepares uterus for implantation, maintains pregnancy.

Deficiency: Low progesterone levels can indicate poor ovary function, and can lead to estrogen dominance. Low levels during pregnancy may cause bleeding, abdominal pain or miscarriage.

Excess: High progesterone levels can cause fatigue, mood swings and vaginal dryness, and occurs during pregnancies with multiples (twins, triplets), and can also occur with ovarian cysts and ovarian cancer.

Timing: Begins to rise just before ovulation, peaks one week after ovulation.





Testosterone is a sex hormone that is produced by the ovaries and adrenal gland in women. Men produce about 10 times more testosterone than women, but it is still an important hormone for women. Testosterone has many functions in the female body including the development of lean muscle, bone density, increasing sex drive and sexual pleasure and contributes to energy levels and feelings of well being.

Function: Helps regulate the function of many organs, including the reproductive tract, muscles, bones, kidneys and the liver.

Deficiency: Low testosterone levels can cause fatigue, depression, low sex drive, loss of muscle tone and bone density, dry skin and thin hair. Other symptoms can include difficulty with concentration, memory loss, sleep difficulties and painful intercourse.

Excess: High testosterone can cause increased acne, increased facial and body hair, increased insulin production, menstrual cycle abnormalities and infertility.

Timing: Peaks around ovulation.


Luteinizing hormone

Luteinizing hormone (LH) is produced by the pituitary gland in women. The surge of this hormone causes the release of the ripe egg from the ovary and the formation of the corpus luteum. Ovulation predictor kits detect the surge of the LH and a positive test indicates that ovulation will occur within 24-48 hours.

Function: Stimulates the release of the egg at ovulation, also stimulates corpus luteum to produce progesterone.

Deficiency: A deficiency is usually seen with an FSH deficiency, can cause delayed puberty, infertility and decrease in levels of sex hormones.

Excess: High levels of LH outside the normal surge can cause irregular periods and is associated with PCOS.

Timing: Rises during weeks 1 and 2, surges at ovulation.


Follicle stimulating hormone

Follicle stimulating hormone (FSH) is produced by the pituitary gland. It is essential to both men and women in development during puberty and the function of the ovaries and testes in adults. FSH in women stimulates the follicles in the ovary to ripen prior to ovulation. The surge of luteinizing hormone causes the release of one of these ripened eggs and the formation of the corpus luteum. Progesterone produced by the corpus luteum inhibits the release of FSH during the second half of a woman's cycle.

Function: Stimulates the follicles in the ovaries to ripen.

Deficiency: Symptoms of low levels can include irregular menstrual cycle, weight gain, increased hair growth and deepening of the voice.

Excess: High FSH levels are associated with menopause, and decreased ovarian reserve or PCOS. In younger women can indicate poor egg quality and premature ovarian failure.

Timing: Rises during the first half of the cycle, inhibited by progesterone during the second half of the cycle.





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