Estrogen

Estrogen is the primary female sex hormone, playing a vital role far beyond reproduction. It not only regulates the menstrual cycle and supports fertility, but also contributes to sexual development, bone strength, cardiovascular health, brain function, skin elasticity, and metabolism. Estrogen even influences mood, memory, and energy levels, making it essential for overall wellbeing.

Although both men and women produce estrogen, women have much higher levels during their reproductive years. These levels rise and fall naturally throughout life, with significant changes during puberty, pregnancy, perimenopause, and menopause.

There are four naturally occurring forms of estrogen - estradiol (E2), estrone (E1), estriol (E3), and estetrol (E4). Each one has distinct strengths and functions, and their balance shifts across different stages of a woman’s life. Understanding how these estrogens work helps explain why hormone changes can affect so many aspects of health.

 Estrogen influences more than reproduction. It plays a role in:

• Bone health: Protects against osteoporosis by maintaining bone density.
   
• Cardiovascular health: Helps regulate cholesterol and vascular function.
   
• Brain & cognition: Affects memory, mood, and sleep regulation.
   
• Immune system: Modulates inflammation and immune response.
   
• Metabolism: Supports fat distribution and insulin sensitivity.

Estrogen Dominance

Occurs when progesterone levels fall faster than estrogen, leading to relative imbalance. May cause heavy periods, bloating, or mood swings.
 

Surgical Menopause

Rapid estrogen loss after ovary removal can trigger severe symptoms.
 

Cancer Risks

Elevated estrone after menopause may increase risk for breast and endometrial cancers.

Symptom Relief
Estrogen is the most effective treatment for hot flashes, night sweats, and vaginal dryness. It can also help improve sleep, mood, and overall quality of life for many women.

Bone Protection
Estrogen slows bone loss and reduces the risk of osteoporosis and fractures after menopause.

Formulation Differences
Options include oral tablets, transdermal patches, gels, and sprays. Transdermal routes may have lower risks for blood clots compared with oral estrogen. Vaginal estrogen is effective for local symptoms and generally has minimal systemic absorption.

Delivery Methods

• Systemic estrogen (oral, patch, gel, spray) treats hot flashes, night sweats, and bone loss.
   
• Local estrogen (cream, tablet, ring) targets vaginal dryness and urinary symptoms.
   
• Non-oral systemic estrogen is often preferred in women at higher risk of blood clots.
   

Side Effects
May include breast tenderness, bloating, nausea, headaches, or leg cramps. Some women may also notice skin irritation with patches or gels.

•  Estradiol is the dominant estrogen before menopause; estrone takes over afterward.
   
• Estrogen decline drives many menopausal symptoms, including hot flashes and GSM.
   
• It plays major roles in bone, brain, heart, immune, and metabolic health.
   
• Treatment may include MHT/HRT, lifestyle changes, and targeted supplements.