Most people only think about their menstrual cycle during the time that they get their period, but in actuality, there are 4 stages of the menstrual cycle. The more you know, the better you flow, so let’s dive in!
Menstruation

The most well-known stage of the menstrual cycle is Menstruation. This first stage begins when someone gets their period—when the thickened lining of the uterus, which would support a pregnancy, is no longer needed and sheds through the vagina.
Menstruation typically lasts 3-7 days, but the duration varies from person to person.
Follicular Phase

The follicular phase begins on the first day of menstruation and ends with ovulation, creating an overlap of phases. The follicle-stimulating hormone stimulates the ovary to produce around five to 20 follicles (tiny nodules or cysts), which bead on the surface.
Each follicle houses an immature egg; most often, only one follicle will mature into an egg while the others die.
Ovulation

Typically occurring between days 11 and 21 of the menstrual cycle, the ovulation stage is when someone is most likely to get pregnant.
Can you get pregnant when you’re not ovulating?
Ovulation begins when a mature egg is funneled into the fallopian tube and toward the uterus by waves of tiny, hair-like projections. The life span of the typical egg is only around 24 hours. Unless it meets a sperm during this time, it will die.
Luteal Phase

Once ovulation occurs, the follicle that contains the egg transforms into something called a corpus luteum and produces progesterone and estrogen. The luteal phase often involves hormonal changes such as mood changes, headaches, acne, bloating, and breast tenderness.
If an egg is fertilized, progesterone supports the early pregnancy. If no fertilization occurs, the corpus luteum will break down between 9 and 11 days after ovulation. This results in a drop in estrogen and progesterone levels, bringing us ALL the way back to the first stage of menstruation if no pregnancy has occurred.
Sources: Better Health Channel and Healthline