These changes can causecramps, breast pain, fatigue, mood swings, and upset stomach.
Individual symptoms may vary since everyone’s menstrual cycle is unique.
Other body changes during the menstrual cycle are less obvious.

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The menstrual cycle is controlled by several hormones, includingestrogenandprogesterone, which are produced by follicles in the ovaries.
Hormone shifts throughout the month may affect your mood and energy levels.
This article explains what happens to your body on your period.
What Happens to Your Body on Your Period?
Your period is just one part of the menstrual cycle.
An ovarian follicle is a small, fluid-filled sac in theovarythat contains an egg.
Theovaries contain about 400,000 folliclesby the time puberty begins.
FSH causes several ovarian follicles to undergo maturation.
Decreased progesterone levels may have a positive effect on you.
You may hear this referred to as the “fertile window.”
Cervical mucus is a commonsymptom of ovulation.
You may notice it in your underwear or when you use the restroom.
Thedischargeis typically clear, stretchy, and slippery like a raw egg white.
It lasts about 14 days and ends when you get your period.
This structure produces progesterone and estrogen.
The rising hormone levels help thicken the endometrium.
A period then marks the end of the luteal phase and the start of a new menstrual cycle.
This gives a signal to the pituitary gland and stimulates the production of FSH and LH.
When these hormones work harmoniously, normal menstrual cycles occur.
Summary
The average menstrual cycle is 28 days long.
Shifts in estrogen, progesterone, and other reproductive hormones can cause various symptoms throughout the month.
Premenstrual symptoms like cramps and fatigue as well as clear discharge during ovulation are common.
You may also notice changes in your mood and energy levels, particularly during the follicular and luteal phases.
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