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Understanding the Four Phases of the Menstrual Cycle

The Four Phases of the Menstrual Tracked On PhoneIt’s a common misconception that the term “menstrual cycle" only refers to the days when a woman gets her period. However, the menstrual cycle has four phases that all work together to prepare the body for pregnancy.

Below, we take you through the four phases of the menstrual cycle, giving you a better understanding of the female reproductive system. The more you know about your menstrual cycle, the better you can take control of your health.

Keep reading to learn more!

What Is the Menstrual Cycle?

The menstrual cycle is a complex sequence of events that occurs each month and prepares the female body for a potential pregnancy. It also makes your body have a period if pregnancy doesn't happen. It involves changes in hormone levels, the uterus, and the ovaries. The length of a menstrual cycle can vary from person to person but most commonly lasts around 28 to 30 days.

The start of a woman's menstrual cycle is usually marked by her first menstrual period, typically between the ages of 9 and 15. It is common for these early cycles to be more irregular, which often improves with time. This cycle will continue each month until menopause, which generally happens when a woman reaches her 40s or 50s.

The Four Phases of the Menstrual Cycle

1. Menstruation

Menstruation, or a period, is when uterine blood and tissue come through the vagina. If a woman doesn't get pregnant the previous month, the uterus sheds its lining, causing the period. Menstruation happens once a month, usually every 28 to 30 days, and lasts 3 to 7 days. The first day of a woman's period marks the start of a new menstrual cycle.

2. Follicular phase

The follicular phase is the longest phase of the menstrual cycle. It begins on the first day of a woman’s period and usually lasts about 14 to 21 days until ovulation happens. During this phase, the brain releases a follicle-stimulating hormone (FSH), which helps eggs grow in little sacs called follicles on the ovaries. Only one of these eggs becomes the 'chosen one' and grows bigger, releasing more estrogen. This estrogen makes the lining of the uterus thicker, preparing it for a possible pregnancy.

3. Ovulation

Ovulation is when a mature egg is released from one of the ovaries. It usually occurs around the middle of the menstrual cycle, between days 14 to 16 in a typical 28-day cycle, and lasts about 12 to 24 hours.

During ovulation, the body releases a hormone called the luteinizing hormone (LH). The LH tells the matured egg it's time to come out of its sac in the ovary. Once released, the egg travels down the fallopian tube, where it can be fertilized by sperm. If the egg fertilizes, it attaches to the uterine lining, marking the start of a pregnancy. If the egg is not fertilized, the lining of the uterus sheds, and menstruation (a period) occurs.

Some signs and symptoms can help tell a woman she is ovulating, including thin and stretchy discharge (resembling an egg white), breast soreness, and mild lower abdomen pain.

Ovulation and pregnancy

A woman is most likely to get pregnant in the five days leading up to ovulation and the day of ovulation. While this is a woman’s most fertile phase, it’s important to know pregnancy is still possible at any point in the menstrual cycle. That's because a woman’s ovulation window may change monthly, and sperm can stay in the body for up to five days. Therefore, even if it's less likely, pregnancy can happen from unprotected sex at any time during the menstrual cycle, including menstruation.

Have birth control questions? We have the answers. Read our complete birth control guide for a comprehensive overview of non-hormonal and hormonal birth control options.

4. Luteal phase

The luteal phase begins after ovulation and lasts until the start of the next menstruation phase (period). During this phase, a special structure or cyst called the corpus luteum is formed in the ovary. This cyst releases hormones, like progesterone, that prepare the uterus (womb) for a possible pregnancy. It makes the uterus lining thick and ready to nourish a growing fetus if the egg gets fertilized.

The corpus luteum eventually breaks down without pregnancy, and the hormone levels drop. This process tells the body to remove the thickened uterus lining, which causes a new menstrual cycle.

Importance of Tracking Your Menstrual Cycle

Tracking your menstrual cycle can be incredibly valuable for taking charge of your reproductive health and overall well-being. The following are all reasons why you should track your menstrual cycle.

  • Predict Your Periods — Tracking your cycle helps you know when to expect your next period.

  • Understand Your Body — Your menstrual cycle can tell you a lot about your health. Keeping track can help you notice any irregularities or changes that need attention. For instance, if your periods suddenly become irregular or painful.

  • Know Your Fertile Days — If you're thinking about starting a family someday or avoiding pregnancy, tracking your menstrual cycle can help you identify your most fertile days. Although, remember getting pregnant is possible at any stage of the menstrual cycle.

  • Manage PMS (Pre-Menstrual Syndrome) Symptoms — Those days when your emotions might be all over the place. By tracking your cycle, you can anticipate these mood swings, cramps, and other PMS symptoms, which means you can better plan and care for yourself during those times.

  • Identify Patterns — Over time, you'll notice patterns in your cycle. Some people experience changes in energy levels, moods, or cravings throughout their cycle. Knowing these patterns can help you schedule activities, self-care, and exercise at times that work best for you.

So, whether you use a period-tracking app, a good old-fashioned calendar, or a journal, taking the time to track your menstrual cycle can empower you with knowledge about your body and health.

Everyone’s cycle is different; it might take a few months or even years to see a clear pattern. Embrace this journey of understanding your unique cycle, and remember, your menstrual cycle is a beautiful and natural occurrence that signifies your reproductive health!

Learn about the different types of menstrual cycle problems that can affect a woman’s natural flow. Read our blog post!

Talk to Your Moreland OB-GYN Doctor

Having a few uncomfortable symptoms attached to your menstrual cycle is completely normal. Although, if you are experiencing any debilitating pain or changes to your normal menstrual cycle or period, scheduling an appointment with a trusted provider is a great place to start.

If you’re concerned you have a menstrual cycle problem, please schedule an appointment with Moreland OB-GYN. Our team of caring physicians and advanced practice providers will take the time to discuss your needs and walk you through our treatment solutions.

We are also proud to provide a full range of teen healthcare services, where we provide young women with the guidance and care needed to answer any questions related to their body and reproductive health.

Schedule an appointment today!

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