The Hormones in HRT

Hormones guide a women’s body through all of her life stages from puberty to pregnancy to perimenopause to menopause and beyond.

To understand their role it is necessary to understand who the players are.   One physician describes each hormone as a member of a band, all playing different instruments but contributing to one song.

The Players:  Progesterone, Estrogen, DHEA, Thyroid, and Testosterone

Progesterone  Progesterone is produced by the ovaries and the adrenal glands and in the placenta during pregnancy.  In women progesterone levels are relatively low during the pre-ovulatory phase of the menstrual cycle, rise after ovulation and are elevated during the luteal phase.  Progesterone is also stored in the adipose tissue.  To replace or supplement progesterone can be synthetic or bio-identical and come in the form of pills, creams, and vaginal gels.

Estrogen  The ovaries and the adrenal glands, placenta, liver and breasts also produce estrogen.  It is comprised of three compounds, estrone, estradiol and estriol and is the main sex hormone in women.  Estrogen contributes to the development of secondary sex characteristics that define the differences between men and women.  Estrogen levels control the menstrual cycle and though found in men it is greater in women, especially in women of childbearing years.

DHEA  DHEA is another hormone made by the body that has sometimes been referred to as “the mother of all hormones”.  It is produced in the adrenal glands and in the liver.  In men, the testes also secrete DHEA.  DHEA diminishes with age and when supplemented or replaced thought to reverse the aging process, improve cognitive thinking and reduce the symptoms of menopause.

Thyroid  The thyroid gland being one of the largest endocrine glands in the body controls how the body uses fat, makes protein and works with other hormones.   The thyroid gland produces two hormones; triiodothyronine (T3) and thyroxine (T4). TSH is often measured through blood tests to determine if the thyroid is hyperactive or hypoactive; TSH  regulates hormonal output and stands for thyroid-stimulating hormone.

Hyperthyroidism describes an overactive thyroid, the thyroid is overproducing T3 and T4.   This condition often leads to the most common hyperthyroid disease known as Graves disease.

By contrast hypothyroidism is an underactive thyroid and results in low production of T3 and T4. Patients with either form of thyroid disease need to seek treatment from health care professionals.

In postpartum women there is another form of thyroid disease called thyroiditis which is a condition that occurs after the birth of a child and can start as overactivity of the gland followed by underactivity of the gland.   The thyroid actually becomes inflamed and in many cases the gland may recover and resume normal hormonal function.

What is important to know is not to ignore symptoms of thyroid dysfunction.  In hyperthyroidism it presents as goiters, protruding eyes, excessive sweating and palpitations, weight loss with increased appetite, and muscle weakness.  In hypothyroidism it can present as abnormal weight gain, slow heartbeat, cold intolerance, hair loss and fatigue.

Testosterone  Men are not the only gender that need and produce testosterone. The ovaries produce testosterone along with estrogen in relatively small quantities.  The adrenal glands also produce testosterone in women and they are involved in growth, maintenance and repair of reproductive tissues.  In women testosterone may be linked to libido but for women there is an emotional element involved.  It is more complicated than treating the physical desire as in men.

SHBG  Sex Hormone Binding Globulin SHBG is a protein produced by the liver that binds to testosterone and estrodial (estrogen) and transports them in the blood.  SHBG controls the amount of testosterone in the body and is very important when all hormones start to decrease in postmemopausal women.

When considering hormone replacement you want those that don’t increase SHBG because they interfere with libido in older women.   Transdermal estrogens, those not passing through the liver, have been found not to increase testosterone.