Estrogen – Everything You Need to Know


Estrogen is the main female hormone that ensures the development and function of the reproductive system. It also gives women certain female characteristics, including breast enlargement and pubic hair.

Researchers highlighted the role of estrogen in promoting bone health, cardiovascular function, and cognitive function. For this reason, postmenopausal women deal with multiple health complications, including an increased risk of heart disease and osteoporosis.

The organs that produce estrogen are the ovaries, adipose tissues, and adrenal glands. While both females and males produce this hormone, estrogen in males plays an irrelevant role.

In this article, we will cover several aspects of estrogen, including its benefits, deficiency, side effects, and potential uses as a treatment.

What are the types of estrogen?

There are several types of estrogen, including:


This type of estrogen is found in the body after menopause. It has a weaker potency but can be converted to estrogenwhen the body deems it necessary.


Estradiol is the form of estrogen that’s present in males and females. During reproductive years, estradiol is the most abundant.

Here are some side effects of high estradiol levels:

  • Acne
  • Decreased libido (i.e., loss of sex drive)
  • Depression and mood swings
  • Osteoporosis
  • Higher risk of breast cancer


Estriol levels increase during pregnancy to help the uterus grow in size and prepare the body for delivery.

What is the function of estrogen?

Estrogen has different physiological effects based on the organ it impacts.

Ovaries – Estrogen is indispensable for the growth of the ovum.

Vagina – Estrogen promotes the secretion of vaginal liquids and maintains the thickness of the canal.

Uterus – Estrogen regulates the secretions inside the uterus and its thickness.

Breasts – Estrogen promotes the enlargement of breast tissues. It also blocks the production of milk after weaning.

As you can see, estrogen plays several crucial roles in female physiology.

The levels of estrogen during different stages of life

Estrogen concentrations vary from one person to another. In fact, the levels of this hormone fluctuate dramatically during a single menstrual cycle. During perimenopause and menopause, the sharp decline in estrogen levels can lead to hot flashes and mood swings.

Here are some of the factors that influence estrogen levels:

  • Puberty
  • Pregnancy
  • Menopause
  • Obesity
  • Anorexia nervosa (i.e., a mental disorder characterized by severe caloric restriction)
  • Strenuous physical activity
  • Certain drugs (e.g., ampicillin, steroids, tetracyclines)
  • Turner’s syndrome and other congenital disorders
  • Diabetes mellitus and high blood pressure
  • Pituitary deficiency
  • Polycystic ovary syndrome (PCOS)
  • Tumors affecting the ovaries or adrenal glands

Estrogen imbalance

When you have estrogen imbalance, you are at risk of several complications, including:

  • Irregular menstrual cycle
  • Secondary amenorrhea
  • Spotting during menstruation
  • Excessive bleeding
  • Severe perimenstrual symptoms
  • Night sweats and hot flashes
  • Sudden mood swings
  • Sleep disorders (e.g., insomnia)
  • Rapid weight gain around the waist and hips
  • Lumps in the breast – Usually benign
  • Unexplained fatigue
  • Vaginal dryness and low libido
  • Dry skin
  • Depression and anxiety

Note that many of these side effects are seen during menopause.

When estrogen levels increase due to hereditary conditions in men, you can expect these symptoms:

  • Erectile dysfunction
  • Gynecomastia (i.e., man boobs)
  • Infertility
  • Weight gain

Men with high levels of estrogen may also experience low libido.

Estrogen sources and uses

If you are dealing with estrogen deficiency, your physician may prescribe hormone replacement therapy (HRT), which could contain:

  • Synthetic estrogen
  • Bioidentical estrogen
  • Estrogen extracted from pregnant mares (through urine)

Estrogen therapy

The purpose of estrogen therapy is to regulate the levels of this hormone in order to mitigate the symptoms of deficiency. We refer to this treatment as hormone replacement therapy (HRT).

Sometimes, your doctor will prescribe estrogen alone, which may be called estrogen replacement therapy. On other occasions, you may benefit from both estrogen and progestin (i.e., a synthetic form of progesterone).

Depending on your condition and some factors, you can supply your estrogen levels using pills, patches, nasal sprays, injections, vaginal creams or rings, and skin gels.

Symptoms that may benefit from HRT include:

  • Hot flashes
  • Vaginal dryness
  • Dyspareunia (i.e., pain during sexual intercourse)
  • Mood swings
  • Sleep disorders
  • Anxiety
  • Decreased libido

Furthermore, hormone replacement therapy can aid postmenopausal women who are suffering from osteoporosis.

With all of that said, some side effects of HRT are:

  • Breast soreness
  • Bloating
  • Headaches
  • Leg cramps
  • Indigestion (e.g., constipation)
  • Nausea and vomiting
  • Vaginal bleeding
  • Swelling of the feet due to fluid retention

Unfortunately, researchers linked certain types of hormone replacement therapy with a higher risk of breast cancer, blood clots, and strokes. When you speak with your doctor about HRT, he/she will present the benefits and risks of this treatment to help you make an informed decision.

Aside from menopause, estrogen replacement therapy helps people with the following conditions:

  • Primary ovarian insufficiency
  • Acne vulgaris
  • Prostate cancer (some cases)
  • Delayed puberty due to Turner’s syndrome

Finally, we should note that hormone therapy is not a one-size-fits-all type of treatment. If you have a family history of breast cancer or thyroid disorders, your doctor may suggest staying away from this treatment. Alternatively, they would suggest estrogen and progestin at the same time.

Transitioning to female

For individuals who were assigned as males at birth but wish to transition to females, estrogen replacement therapy may be of aid.

Estrogen therapy helps the person express female secondary traits, which include less body hair and large breasts. However, estrogen therapy is not the only treatment used in this situation. Your doctor will suggest an array of treatments to help you transition.

Birth control

Contraceptive pills can either contain estrogen and progestin or progestin alone. The purpose of these pills is to prevent ovulation by altering the physiological fluctuations of female hormones during the menstrual cycle. Additionally, progestin thickens the cervix, making it very difficult for the sperm to reach the ova.

Birth control pills also help women with premenstrual symptoms (PMS).

However, they may increase the risk of the following health complications:

  • Heart attacks and strokes
  • Blood clots
  • Nausea and vomiting
  • Pulmonary embolism
  • Headaches
  • Irregular bleeding
  • Increased breast tenderness and swelling
  • Weight gain

Some research suggests that birth control pills may increase the risk of breast cancer, especially in smokers over the age of 35.

Food sources of estrogen

Some plant-based foods have high levels of phytoestrogen. However, studies are not conclusive about how this form of estrogen affects the body.

Here are some foods elements with high levels of phytoestrogen:

  • Seeds and grains
  • Nuts
  • Fruit
  • Wine
  • Cruciferous vegetables
  • Soy
  • Berries

There is some anecdotal evidence that foods with phytoestrogens can help with symptoms of perimenopause and menopause.

Dietary supplements

Phytoestrogens are a form of estrogen found in plants. Supplement manufacturers use this type of estrogen in their products.

Examples of plants that contain phytoestrogen include:

  • Black cohosh
  • Red clover
  • Soy isoflavones

Despite the hype surrounding this type of estrogen, there is conflicting evidence about its effectiveness on the human body. Additionally, only a few scientific studies inspected the safety of these products. More importantly, the long-term effects of phytoestrogens are still unclear.

The U.S. Food and Drug Administration (FDA) does not regulate the field of supplements and non-pharmacological drugs. Therefore, the content and quality of phytoestrogen supplements remain unverified.

Make sure to speak with your doctor before taking estrogen supplements or any other unregulated products.