Up to two weeks before a menstrual period, hormone-driven changes in the body trigger a collection ofpremenstrualsymptoms (PMS). These changes can causecramps, breast pain, fatigue, mood swings, and upset stomach. Individual symptoms may vary since everyone’s menstrual cycle is unique.
This article explains what happens to your body on your period. It breaks down the four phases of the menstrual cycle, explaining how key events that occur during each phase of the menstrual cycle may affect you.
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What Happens to Your Body on Your Period?
Your period is just one part of the menstrual cycle. The menstrual cycle consists of four distinct phases:
Here’s whatchanges happen in the bodyduring each phase of the menstrual cycle:
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Menstrual Phase
The first phase of the menstrual cycle is the menstrual phase, also known as your period. The menstrual phase starts on day one when you get your period, and ends when your period stops, usually around days five to seven.
Leading up to a period, increased levels of the hormone progesterone widen milk ducts in the breasts and prepare the uterus for pregnancy.When implantation doesn’t occur, progesterone levels quickly withdraw, triggering theendometrium(uterine lining) to shed and the period to begin.
According to the International Federation of Gynecology and Obstetrics, menstruation should last no longer than eight days.If yours lasts longer or you do not have a period at all, consult with your healthcare provider.
While on your period, you may feel one or more of the following symptoms:
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Follicular Phase
The second phase of the menstrual cycle is the follicular phase. This phase overlaps with your menstrual phase, beginning on day one with your period and ending when you ovulate, around day 14.
During the start of the follicular phase, the anterior pituitary gland triggers rising levels of follicular stimulating hormone (FSH). FSH causes several ovarian follicles to undergo maturation. Between days 10 to 14 of the menstrual cycle, just one ovarian follicle will fully mature into an egg.
It’s also during this phase that progesterone decreases and estrogen peaks, causing the endometrium to thicken in preparation for ovulation and possible pregnancy.
Decreased progesterone levels may have a positive effect on you. Research shows that lower progesterone levels are linked to greater strength, power, and energy in athletes during the follicular phase of their cycles.
The most fertile period of a normal menstrual cycle is the last three days of the follicular phase leading up to ovulation. You may hear this referred to as the “fertile window.”
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Ovulation
The third phase of the menstrual cycle is ovulation,occurring around day 14 of a 28-day cycle. During this time,luteinizing hormone(LH) levels suddenly surge, triggering ovulation within about 24 to 48 hours.Estrogen levels decrease during the LH surge while progesterone begins to rise again.
Sperm is viable for approximately three to five days, but the released egg is only viable for one—the day of ovulation. Therefore, conception is most likely to occur if you have intercourse in the three days leading up to ovulation.
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.
If you are trying to get pregnant, the best time to have intercourse is when you notice cervical mucus as it means you are ovulating.
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Luteal Phase
The fourth stage, called the premenstrual orluteal phase, occurs around day 15 of the menstrual cycle. It lasts about 14 days and ends when you get your period.
During the luteal phase, the follicle that released an egg in ovulation changes into a structure called the corpus luteum. This structure produces progesterone and estrogen. The rising hormone levels help thicken the endometrium.
If the egg is not fertilized with sperm, the corpus luteum dissolves, hormone levels decline, and the endometrium gets ready to shed. A period then marks the end of the luteal phase and the start of a new menstrual cycle.
Female Anatomy and Function
Hormones and Your Menstrual Cycle
The menstrual cycle starts with yourendocrine glandsbecause they produce the hormones that determine when you get your period, the amount of menstrual flow, and what happens to your reproductive organs.
Seven hormones serve as chemical messengers to your reproductive system:
During your menstrual cycle, the hypothalamus first releases GnRH. This gives a signal to the pituitary gland and stimulates the production of FSH and LH.
Summary
The average menstrual cycle is 28 days long. Each menstrual cycle is comprised of four distinct phases: the menstrual and follicular phases, ovulation, and the luteal phase.
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.
13 Sources
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