Phases of the Menstrual Cycle
Regardless of if a woman has the desire to become pregnant, having a healthy menstrual cycle is essential. This is because of the sex hormones that are produced during each phase of the cycle and their protective effect on the body. The menstrual cycle can be broken down into three main phases: the follicular phase, the ovulatory phase, and the luteal phase.
Follicular phase:
The first half of the menstrual cycle is called the follicular phase. This spans from day 1 of menstruation to ovulation. Estrogen is the key hormone during this phase. The backstory of estrogen produced during the follicular phase can be summarized by this: Shortly after menstruation begins, the ovaries receive a message from the brain via the hormone follicule stimulating hormone (FSH), which signals that a new cycle has begun and to start developing follicles (maturing eggs). As these follicles are developing, they release estrogen. Eventually FSH drops back down and one follicule continues developing to be the chosen egg for ovulation this cycle. Estrogen helps to thicken up the uterine lining, since this lining was just shed during menses. A thickened uterine lining is essential for an egg to be able to implant, should conception occur. Outside of the uterus, estrogen is protective for bone, heart, and brain health. From a beauty perspective, estrogen helps our skin hold water and supports elasticity, which makes it plumper and more moisturized during this phase.
Ovulatory Phase:
When the brain senses that there is a certain level of estrogen produced, it will release luteinizing hormone (LH). LH is a message to the ovaries that it is time to release an egg. One ovary is chosen to release an egg and thus, ovulation occurs.
Luteal Phase:
After ovulation occurs, the luteal phase begins. Progesterone is the star of the show during the luteal phase. The progesterone backstory is as follows: During ovulation, an egg is expelled and what is left over where the egg once was becomes the corpus luteum. I like to think of the corpus luteum as an empty eggshell. The corpus luteum releases progesterone during the luteal phase. Progesterone = “pro-gestation”. It helps support the uterine lining to make it a warm and cozy place for an egg to implant, should conception occur this cycle. It prevents uterine cramping during this phase, which is also important if pregnancy the goal. Progesterone is also essential to balance out the effects of estrogen, and can have a calming effect on the body and mind.
Interesting fact: Body temperature increases just slightly after ovulation occurs due to the presence of progesterone, which is why tracking basal body temperature is a way to monitor signs of fertility
As we covered in the previous blog, Menstruation 101, a normal and healthy menstrual cycle ranges from 24-38 days in length. Within that month-ish span of time, the follicular phase is changeable because it continues until ovulation occurs and ovulation can vary. The luteal phase is more fixed and in a healthy woman will typically always last 12-16 days long.
Having a healthy menstrual cycle means that during each phase the body produces optimal amounts of each hormone to keep the whole system in balance. When an imbalance occurs, symptoms can occur. One way to assess hormone balance is through lab testing. It can also be helpful to track signs of fertility, as this can give insight to if ovulation is occurring and when. One of my favorite books to use to start tracking the menstrual cycle and signs of fertility is Taking Charge of your Fertility by Toni Weschler.
See the link below if you would like to read more about each phase of the menstrual cycle and see a helpful graph that explains things further:
If you would like to learn more about your personal menstrual cycle through a hormone lab assessment, schedule a free discovery call to connect!