Definition

Hormones and Your Menstrual Cycle

Choose a preferred language

A person's monthly period (menstrual cycle) is controlled by changing levels of certain hormones. These hormones travel through the blood. Two hormones, estrogen and progesterone, play a big role in the menstrual cycle. They are made in the ovaries (where eggs are stored).


The menstrual cycle

Hormones help the uterus get ready for pregnancy. The ovaries are stimulated to produce an egg through a complex hormonal process that includes the brain. The ovaries make the hormone estrogen. Once an egg is released from one of the ovaries, they make progesterone. After the egg is released, it goes through the fallopian tube. Then it enters the uterus. If the egg is fertilized, a person becomes pregnant. If this doesn't happen, the egg is shed along with the uterine lining. This occurs as progesterone levels drop quickly without pregnancy. This shedding leads to bleeding. This is called menstruation.

Reproductive organs related to menstruation showing uterus, ovaries, a released egg, fallopian tube, and thickened uterine lining.


Symptoms you may have

During your period (menstruation), you may have different physical and emotional symptoms. These can include:

Physical symptoms:

  • Menstrual bleeding

  • Cramping

  • Headache

  • Breast soreness

  • Bloating

  • Increased and thickened vaginal mucus

Emotional symptoms:

  • Tiredness

  • Sadness

  • Feeling grouchy

  • Feeling moody

Featured in

Online Medical Reviewer: Daphne Pierce-Smith RN MSN

Online Medical Reviewer: Rajadurai Samnishanth Researcher

Online Medical Reviewer: Raymond Turley Jr PA-C

Date Last Reviewed: 01/01/2025

© 2000-2025 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.

Your family’s health is our priority.

From routine checkups to specialized pediatric care, our family of doctors is here for yours.

Find a Doctor
Related Articles
Read article
OB/GYN
Understanding Periods

A period is the result of a cycle that takes place inside a girl's body. This menstrual cycle makes it possible for women to have babies. The cycle begins with ovulation, when an egg is released and begins its journey.

Read article
OB/GYN
The Menstrual Cycle: An Overview

A woman is generally most fertile (able to become pregnant) a few days before, during, and after ovulation.

Read article
OB/GYN
Understanding the Normal Menstrual Cycle

A normal menstrual cycle is described. And it's rare but possible to become pregnant during your period, especially if your cycle is irregular.

Read article
OB/GYN
Low Estrogen Levels in Menopause

In addition to regulating the menstrual cycle, estrogen affects the reproductive tract, the urinary tract, the heart and blood vessels, bones, breasts, skin, hair, mucous membranes, pelvic muscles, and the brain.