What is a Normal Cycle?
Do you ever wonder why your best friend has a regular menstrual cycle while yours is unpredictable? And why does everyone think a cycle should be 28 days when yours takes 32? Or 25? What is a normal period, anyway?
The answer is that everyone’s cycle is unique, and sequential cycles in the same woman may be slightly different and still be considered normal. Menstrual cycles are managed by the cyclical nature of the hormones Estrogen, Progesterone, Luteinizing Hormone (LH), Follicle Stimulating Hormone (FSH), and Gonadotropin-Releasing Hormone (GnRH). The interdependent relationship between these hormones creates an optimal environment for ovulation, uterine lining growth and maintenance, conception, and implantation of an embryo.
The average menstrual cycle length is 21 – 35 days. Day 1 of the cycle coincides with the first day of menses (your period). The cycle can be split into two main phases: Luteal and Follicular.
The Luteal Phase
The Luteal Phase begins after ovulation and ends with the beginning of your next period. The key hormone in this phase is progesterone. The dip in progesterone levels at the end of this phase cues your body to release the endometrial tissue that has been built up in the uterus, thus beginning your period.
Is My Luteal Phase Normal?
In cases where cycles are less than 28 days, progesterone levels might be the culprit. Adequate progesterone levels are important to maintain the endometrial lining for the entire Luteal Phase. Spotting in the week prior to your period is another clue that your progesterone levels may not be high enough. Lab work to measure your progesterone level should ideally be done in the middle of the Luteal Phase (Day 21, of a 28 Day cycle).
In cases where cycles are longer than 28 days let’s look at the Follicular Phase of your Menstrual Cycle for some explanation.
The Follicular Phase
This phase is made up of two parts: Menses and Pre-Ovulatory. If you are not pregnant, your estrogen and progesterone levels naturally drop and cue the shedding of the endometrial lining of your uterus. Day 1 of your Menses (period) is considered Day 1 of your new menstrual cycle.
Within the first few days of the new cycle, hormone signals from the brain begin to increase. The first hormone, FSH, helps to stimulate maturation of one of your ovarian follicles. As the follicle matures, it releases estrogen. Estrogen is paramount in building the endometrial lining and contributing to the changes in cervical mucous that promote conception.
Through a series of feedback loops, a second hormone from the brain, LH, also increases during the Follicular Phase. The LH peaks just before ovulation (day 14 of a 28-day cycle) and it stimulates the follicle’s release from the ovary. Now the follicle becomes what we normally call “the egg” (ovum), and your Luteal Phase begins again.
Is My Follicular Phase Normal?
Surprisingly, if FSH levels are too high at the beginning of the Follicular Phase, it can contribute to infertility. This is because if FSH is already high, it may not increase enough to stimulate appropriate ovarian follicle maturation. We commonly see this in cases of Polycystic Ovary Syndrome (PCOS).
To create an optimal environment for a developing embryo, there needs to be enough time for the uterus to build an appropriate endometrial lining. In cases where menstrual cycles are significantly longer than 28 days, we must look at the hormones that have a prominent role in the Follicular Phase. If these hormones are not cycling normally, or are unable to reach their desired levels, ovulation may not occur. Then delayed transition into the Luteal Phase will prolong your overall cycle.
Troubleshooting Your Menstrual Cycle
The good news is that you can take action to regulate your menstrual cycle, starting at home. You can track important data during your cycles to create a better picture of the length of the Luteal and Follicuar phases:
- The date each menses begins and ends
- Cramping, heaviness, clots, color
- Presence of spotting (minimal light brown menstrual blood)
- Consistency and amount of cervical mucous (dry, sticky, cottage cheese, egg white, watery)
- Other symptoms: headaches, neck aches, insomnia, cravings, acne, bloating, cramping, mood changes
Your health care provider can analyze this information and suggest lab tests to uncover the root causes of very short or very long periods. Insurance may cover testing of common hormones that can impact cycles (such as LH, FSH, Estrogen, and Progesterone). Other tests that track a variety of hormones throughout the cycle may not be covered by insurance but can be useful to provide a wholistic view of hormone trends through your entire cycle.
Make sure that your provider schedules these tests on the appropriate day of your Luteal and/or Follicular phases order to get the most useful results. This is why tracking your data at home and knowing the timing of your phases is so important!
If you would like to learn more about your own cycle and how to optimize it, make an appointment with Greenhouse Natural Medicine.