The menstrual cycle is often explained using two concepts: menstruation and ovulation. While those are the two main events, they only make up half of the cycle. The menstrual cycle is broken up into four phases:
- Menstruation
- Follicular Phase
- Ovulation
- Luteal Phase
Each of these phases have their own unique characteristics, summarized by the chart below, and explored further in this blog.
Important Hormones
Estrogen: Estrogen (estradiol on the chart) is a female sex hormone that stimulates the growth and maturation of the uterine lining, as well as the maturation of the egg.
Progesterone: Progesterone is yet another female sex hormone, also known as the calming hormone. It balances out the effects of estrogen, and controls and maintains the building of the uterine lining in the case of conception. In the absence of conception, progesterone levels fall, causing the shedding of the uterine lining (menstruation).
Follicle Stimulating Hormone (FSH): FSH stimulates the maturation of the ovarian follicles.
Luteinizing Hormone (LH): LH stimulates the rupturing of the mature ovarian follicle, in order for an egg to be released (ovulation).
The Phases of the Menstrual Cycle
Menstruation
Menstruation occurs in the absence of pregnancy. The lining of the uterus (the endometrium) is shed, as it is no longer needed to support pregnancy. A combination of blood, mucus and tissue from the uterus is expelled through the cervix and vagina.
Length: The menstrual phase of the cycle can be three to seven days in length.
Hormonal changes: Estrogen and progesterone are at an all time low.
How it feels: A lot of people experience painful or uncomfortable periods. Other than that, you might feel withdrawn and introspective. Use this time to rest and center yourself. Menstruation can be viewed as your inner winter.
Follicular Phase
The brain signals to the ovaries to prepare an egg to be released. The endometrium is built back up in preparation for conception. Discharge will start appearing during the later stages of this phase.
Length: The follicular phase starts on day one (it overlaps with menstruation) and can be anywhere between 10 and 22 days, lasting about 14 days on average. It ends when ovulation occurs.
Hormonal changes: High levels of FSH stimulate folliculogenesis, which is the growth and maturation of the follicles. Follicles are small sacs, each containing an immature egg. Many follicles grow in each ovary, until a dominant follicle (the largest and healthiest one) emerges, and the remaining follicles are reabsorbed. The dominant follicle produces estrogen, and when estrogen reaches a certain level, it causes LH to be released. The estrogen stimulates the endometrium to start to thicken yet again.
How it feels: Mood and confidence often improve halfway through the follicular phase. This is a phase of outward focus, and you might start feeling more social and energetic. You may notice feeling more creative. Your follicular phase can be compared to your inner spring; a new beginning.
Ovulation
A mature egg is released from the dominant follicle, travels down the Fallopian tube, and awaits fertilization. This egg only lives for 12 to 24 hours, but since sperm can survive in the body for 5 days, the fertile window (during which it is possible to get pregnant) is 5 to 7 days. Thicker discharge, with an egg white texture, and a slight rise in basal body temperature indicates that ovulation has occurred.
Length: Ovulation occurs around the middle of your cycle (around day 14 if you have a 28 day cycle).
Hormonal changes: The dominant follicle reaches its largest size right before ovulation. Estrogen, along with LH, peaks; the LH causing the release of the egg. After ovulation, the unfertilized egg will die and dissolve. There is a minor peak in FSH.
How it feels: Some people experience mild pain on the side from which the egg is released from the ovary. This is called Mittelschmerz (a German word meaning “middle pain”), and can last for a few minutes or a few days. However, ovulation is generally the phase during which people feel the best. Energy and confidence is at an all time high, and people tend to feel more social. You may feel brighter, stronger, more productive, and even more attractive. Ovulation represents your inner summer.
Luteal Phase
After ovulation, the dominant follicle transforms into the corpus luteum.
Length: A healthy luteal phase generally lasts between 12 and 16 days.
Hormonal changes: LH and estrogen levels drop. The corpus luteum secretes progesterone, and some estrogen, which serves to stimulate the endometrium to thicken further in preparation of the possible upcoming pregnancy. The release of progesterone is the cause of the increase in basal body temperature, and it peaks about half way through this phase.
In the case of an egg being fertilized, the progesterone supports early pregnancy. The rising progesterone levels eventually signal the endometrium to stop thickening and start preparing for the potential implantation of the egg. If pregnancy does occur, human chorionic gonadotropin (hCG) is released (the hormone that pregnancy tests look for), to maintain the corpus luteum and keep the endometrium nice and thick. If pregnancy fails to occurs, the corpus luteum breaks down and is reabsorbed, estrogen and progesterone levels drop, and menstruation occurs once again.
How it feels: People become more self aware and inward focused. The increase in progesterone will have you feeling calm and relaxed. During the second half of the luteal phase, you may experience PMS symptoms and a drop in your energy levels. Now is the time for self-care and quality me-time; your inner autumn.
The menstrual cycle is complex and multifaceted. Each cycle, an egg matures and is released from the ovaries, the uterine lining thickens, and is shed (unless pregnancy is achieved). Then the whole cycle starts again.
With so many different factors involved, it is no surprise that there are so many things that can go wrong, or problems to occur. These problems include, but are not limited to, PCOS and Endometriosis, which you can learn more about here. However, in most cases, it is just a case of realigning your life with your cycle, and living a hormone-balancing lifestyle.
Disclaimer: I am not a medical professional. If you feel something is wrong in your body, seek medical help; this blog does not serve as a replacement for medical interventions.
If you are interested in working with me to achieve this hormone-friendly lifestyle, leave a message below!
