What is Estrogen? Estrogen is a key steroid hormone that helps regulate reproductive health, sexual development, and several systems throughout the body. Estrogen levels naturally rise and fall across the menstrual cycle and typically fall as women approach menopause; these normal changes support ovulation, pregnancy, and other reproductive functions. Persistent or very high or low hormone levels can signal an underlying condition and should be evaluated by a clinician. If you’re considering diet, supplements, or lifestyle changes to influence hormone levels, talk with your health provider first — especially if you have a history of hormone-sensitive conditions. Read on for practical, evidence-based ways people may support healthy estrogen levels and when to seek medical care for symptoms.

What is Estrogen?

Estrogen is a group of steroid hormones that play a central role in female reproductive health and influence many systems in the body. The three main forms—estradiol, estrone, and estriol—predominate at different life stages and together help regulate the menstrual cycle, sexual development, fertility, pregnancy, and changes that occur with aging.

Estrogen works by binding to estrogen receptors (mainly ERα and ERβ) in target cells. These receptors are found in the cell nucleus and on cell membranes; when activated they change gene activity and cellular behavior—for example, stimulating the endometrium to thicken before ovulation or helping maintain bone density. Most estradiol is produced by the ovaries during the reproductive years, estrone is more common after menopause and is produced in adipose tissue, and estriol is produced primarily by the placenta during pregnancy.

For more detail on each form, see the section “What are the Types of Estrogen?” below.

What are the Types of Estrogen?

There are three primary forms (types) of estrogen, each a slightly different form of the same hormone with distinct roles and sources at different stages of life:

  • Estrone (E1): Predominant after menopause. Estrone is produced mainly in adipose (fat) tissue and becomes the more common circulating estrogen once ovarian production declines.
  • Estradiol (E2): The dominant and most potent form during the reproductive years. Produced chiefly by the ovaries, estradiol regulates the menstrual cycle, supports ovulation, and affects bone density, skin, and female sexual characteristics.
  • Estriol (E3): Most abundant during pregnancy. Estriol is produced primarily by the placenta and is often measured in pregnancy-related screening; levels may be assessed via blood or urine testing in obstetric care.

Clinically, tests usually measure estradiol to assess hormone status in nonpregnant people; estriol testing is used mainly in pregnancy screening. See “What Should the Estrogen Levels Be?” for typical lab ranges and timing of testing during the menstrual cycle.

What Should the Estrogen Levels Be?

Typical reference ranges for estradiol (the most commonly measured form of estrogen) vary by sex, age, and phase of the menstrual cycle and can differ between laboratories and assays. Commonly cited approximate ranges are:

  • Premenopausal (varies by cycle phase): roughly 30–400 pg/mL overall—lower in the early follicular phase, peaking around ovulation, and intermediate in the luteal phase.
  • Postmenopausal women: approximately 0–30 pg/mL.
  • Men: roughly 10–50 pg/mL.

Because estradiol fluctuates with the menstrual cycle, clinicians typically time testing to a specific cycle day (for example, early follicular phase) to interpret hormone levels accurately. During ovulation, levels normally rise as part of the reproductive cycle to support egg maturation and uterine changes; if pregnancy does not occur, levels fall as the corpus luteum regresses. Laboratories use different methods and reference ranges, so always compare results to the lab’s stated range and discuss abnormal or consistently low/high hormone levels with your healthcare provider. Blood testing is the standard method for measuring estradiol in nonpregnant people; estriol levels are more commonly assessed in pregnancy screening via blood or urine.

What are the Functions of Estrogen Hormone in the Body?

Estrogen is a multifunctional hormone that signals the body when to start and stop processes related to sexual development and reproductive health, and it also influences other systems (bone, cardiovascular, skin). Below are the main roles estrogen plays at different life stages, with brief clinical notes where relevant.

Puberty and sexual development

During puberty estrogen levels rise and drive development of female sexual characteristics: breast growth, widening of the hips, and typical changes in body fat distribution. Estrogen also contributes to maturation of the reproductive tract and secondary characteristics such as pubic hair patterns and voice changes.

Menstrual cycle and ovulation

Estrogen (especially estradiol) helps regulate the menstrual cycle by promoting follicular growth in the ovaries, supporting ovulation, and stimulating the uterine lining (endometrium) to thicken in preparation for possible implantation of a fertilized egg. These cyclic changes in hormone levels are essential for fertility and normal cycle patterns.

Pregnancy and fertility

Estrogen levels rise before ovulation to support egg maturation and modify cervical mucus (making it more favorable to sperm). In pregnancy, placental estrogens (including estriol) help maintain uterine blood flow and support fetal development. Clinically, changes in estrogen are one component obstetricians monitor as part of prenatal care.

Menopause and symptoms

Estrogen levels decline during perimenopause and after menopause, which commonly leads to symptoms such as hot flashes, night sweats, vaginal dryness, mood changes, and sleep disruption. The dominant circulating estrogen shifts from estradiol (E2) during reproductive years to lower levels of estrone (E1) in the postmenopausal period. These hormonal changes contribute to clinical decisions about symptom management, including when hormone therapy may be appropriate.

Bone health and fracture risk

Estrogen helps preserve bone density by balancing bone formation and resorption. After menopause, lower estrogen levels are a major contributor to accelerated bone loss and increased fracture risk; this is a key consideration when assessing osteoporosis prevention and treatment strategies.

Cholesterol metabolism and cardiovascular effects

Estrogen influences lipid metabolism and is associated with higher HDL (“good”) cholesterol and lower LDL (“bad”) cholesterol levels in premenopausal women. These effects may contribute to differences in cardiovascular risk profiles, though the overall impact depends on many factors (age, genetics, lifestyle), and the benefit of estrogen on cardiovascular risk is complex and not a substitute for established risk-reduction measures.

Skin, hair, and connective tissues

Estrogen helps maintain skin elasticity and moisture and supports hair health; declining levels with age can contribute to drier skin and changes in hair. While estrogen can have beneficial effects, the magnitude varies and other factors (nutrition, sun exposure, smoking) also play major roles.

Other roles and clinical notes

Estrogen receptors are widely distributed, so the hormone affects multiple tissues beyond reproduction. Clinically, disturbances in estrogen levels can present with a range of symptoms (reproductive, mood, sleep, bone). If you notice persistent symptoms or significant changes, review your history with a provider—testing (blood estradiol, FSH, etc.) and a tailored plan can help guide treatment. For practical guidance on supporting healthy hormone levels through lifestyle, see “How to Increase Estrogen?” below.

What are the Negative Effects of Low Estrogen Levels?

Low estrogen levels most commonly occur during perimenopause and after menopause, but they can also result from certain medical conditions (for example, Turner syndrome), extreme weight loss, or some disorders that affect ovarian function. Low levels can cause a range of symptoms; some are directly linked to estrogen deficiency while others are multifactorial and should be evaluated by a clinician.

  • Vasomotor symptoms: Hot flashes and night sweats are classic signs associated with falling estrogen levels.
  • Reproductive changes: Irregular or missed periods, reduced fertility, and vaginal dryness (which can cause discomfort during sex) are common when estrogen is low.
  • Musculoskeletal effects: Low estrogen contributes to decreased bone density over time, increasing fracture risk—this is a major postmenopausal health concern.
  • Cognitive and mood changes: People may report headaches, difficulty concentrating, fatigue, sleep problems, irritability, or depressive symptoms; these can be influenced by estrogen but are often multifactorial.
  • Breast and sexual symptoms: Some people notice breast tenderness or changes in libido related to hormonal fluctuations.

If you or someone you care for is experiencing persistent symptoms that could reflect low estrogen (for example, new-onset hot flashes, irregular cycles, persistent vaginal dryness, or unexplained bone loss), consult a healthcare provider. Clinicians commonly evaluate hormone imbalance with a medical history, targeted tests such as blood estradiol and FSH, and, when indicated, imaging or genetic testing (for conditions like Turner syndrome). Management depends on the cause, severity of symptoms, age, and individual health risks.

What are the Negative Effects of High Estrogen Levels?

Elevated estrogen levels may be associated with certain estrogen-sensitive growths (for example, some fibroids, endometrial polyps, or ovarian tumors) and with metabolic patterns that favor fat accumulation. Rather than being the sole cause, high estrogen often reflects an imbalance in hormone regulation; the clinical implications depend on the underlying reason and individual risk factors.

  • Reproductive and breast symptoms: Increased estrogen activity can cause breast tenderness or enlargement and may contribute to heavy or irregular menstrual bleeding in some people.
  • Weight changes: Some individuals notice weight gain, particularly with increased fat around the hips and waist, though weight is also influenced by diet, activity, and other hormones.
  • Headaches and mood: Headaches and mood fluctuations may occur with hormonal imbalances, including periods of relatively high estrogen.
  • Pregnancy risks: In some contexts, abnormal hormone levels can complicate pregnancy or fertility, so clinicians may investigate hormonal causes when pregnancy outcomes are at risk.
  • Cancer risk (context matters): Prolonged unopposed estrogen exposure is linked to higher risk of certain estrogen-sensitive cancers (for example, endometrial cancer and some breast cancers). The degree of risk depends on dose, duration, and individual factors; discuss personal risk with your provider.

If you suspect high estrogen — for example, new or worsening heavy bleeding, rapid breast changes, or unexplained weight gain — seek medical evaluation. Clinicians may order blood hormone tests and imaging (ultrasound) to look for uterine or ovarian conditions and will tailor management based on the cause, symptoms, and overall health. Avoid alarmist conclusions: the presence of a symptom does not automatically mean high estrogen, and many conditions are multifactorial.

How to Increase Estrogen?

If you have low estrogen or want to support healthy hormone levels, some lifestyle changes can help. These approaches are generally supportive rather than a replacement for medical treatment (such as hormone therapy) when that is needed. Always discuss any diet, supplement, or exercise change with your clinician—especially if you have a history of estrogen-sensitive conditions or are pregnant.

Diet and phytoestrogens

Certain plant foods contain phytoestrogens—compounds that have weak estrogen-like activity in the body. Examples include soy products (tofu, tempeh), flax seeds, lentils, and peas. Including moderate portions (for example, a serving of soy or 1–2 tablespoons of ground flax daily) may modestly support hormone balance for some people. Phytoestrogens are not as potent as body-produced estrogen or prescription hormone therapy, and their effects vary by individual. If you have or had estrogen-sensitive breast or uterine conditions, consult your provider before increasing phytoestrogen intake.

Healthy fats and overall nutrition

Adequate dietary fat is important for hormone production. Include sources of healthy fats such as olive oil, avocados, nuts, and fatty fish (salmon) as part of a balanced diet. Ensure sufficient calories and a nutrient-rich diet to avoid extreme weight loss, which can lower estrogen production and disrupt the menstrual cycle.

Exercise and physical activity

Regular moderate exercise and strength training support overall endocrine health. Resistance training helps maintain muscle and can indirectly support healthy hormone balance; aerobic activity supports cardiovascular health. Note that excessive high-intensity training and very low body fat can suppress ovarian function and lower estrogen—aim for balanced, sustainable activity and discuss exercise plans with your clinician if you have irregular cycles.

Vitamins, minerals, and supplements

Some nutrients support general endocrine and reproductive health—examples include vitamin D, magnesium, and B vitamins. However, evidence that specific supplements directly increase estrogen is limited. Use supplements only under medical guidance, particularly if you are pregnant or have hormone-sensitive conditions. Your clinician can check for deficiencies and recommend appropriate dosing.

Stress management and sleep

Chronic stress and poor sleep can disrupt the hormonal axis and contribute to imbalances. Practices such as regular sleep schedules, mindfulness, cognitive-behavioral techniques, and moderate exercise can reduce stress and support healthier hormone levels.

When to consider medical treatment

If lifestyle measures do not relieve symptoms or if low estrogen causes significant issues (for example, severe vasomotor symptoms, osteoporosis, or infertility), discuss medical options with your provider. Prescription treatments—including hormone replacement therapy (HRT) or targeted fertility treatments—are available and chosen based on age, reproductive goals, medical history, and risk factors.

Summary: Moderate diet changes (including phytoestrogens), balanced exercise, good sleep, and addressing nutrient deficiencies can support healthy estrogen levels in many people, but they are not a substitute for clinical evaluation and treatment when needed. Talk to your healthcare professional before making changes if you are pregnant, breastfeeding, or have a history of estrogen-sensitive conditions.

Frequently Asked Questions

How is Estrogen Level Detected?

Estrogen (most often estradiol) is usually measured with a blood test. Your clinician will order a blood draw and the sample is analyzed by a laboratory—the lab report will include reference ranges specific to that assay. In pregnancy, estriol may be measured by blood or urine as part of prenatal screening. Note: timing matters for nonpregnant people—clinicians often time testing to a specific day of the menstrual cycle (for example, early follicular phase) to interpret results accurately.

Which Department Checks Estrogen Levels?

Management depends on the reason for testing. Common specialties involved include endocrinology (hormone disorders), gynecology (menstrual, uterine, ovarian, fertility and pregnancy-related issues), and primary care or internal medicine for initial evaluation. For pregnancy-related concerns, obstetrics teams coordinate care.

Can birth control affect estrogen levels?

Yes. Combined oral contraceptives contain synthetic estrogens and progestins that alter circulating hormone levels and suppress ovulation. Progestin-only methods affect hormones differently. If you’re being tested, tell your provider about any hormonal birth control, as it can change the interpretation of results.

When should I test my estrogen levels during the cycle?

Timing depends on the clinical question. For baseline assessment, clinicians often test in the early follicular phase (cycle days 2–5). To evaluate ovulation or peak estradiol, tests are timed near midcycle. Your provider will tell you the best timing based on your symptoms and goals (fertility evaluation, irregular bleeding, menopause assessment).

How quickly do levels change with treatment?

Response time varies by treatment. Lifestyle changes and supplements can take weeks to months to affect hormone balance; prescription therapies (such as hormone replacement therapy or fertility medications) can change measurable hormone levels within days to weeks depending on the dose and route. Your clinician will set realistic expectations and monitoring intervals.

What should I bring to an appointment about hormone concerns?

Bring a list of current medications (including birth control and supplements), a menstrual history (cycle length, changes, bleeding patterns), any recent lab results, pregnancy history, and a summary of symptoms (hot flashes, mood changes, vaginal dryness, fertility issues, etc.). This helps clinicians choose appropriate tests and specialties (endocrinology, gynecology, or obstetrics).

Estrogen is a key hormone involved in reproductive development, the menstrual cycle, pregnancy, and broader health in women and people assigned female at birth. If you have concerns about symptoms such as irregular cycles, persistent hot flashes, unexplained changes in mood or breast tissue, or fertility issues, contact your healthcare provider to discuss testing and next steps.