As our friends at Clue recently wrote, there is a wide range of normal when it comes to menstrual cycles. Not all women have a textbook 28-day cycle, with ovulation on day 14. For some women, a 34 day cycle is perfectly healthy. For many women, cycle length changes from month to month. Much of this natural variation is healthy and normal.
But not all variation is healthy. By tracking your cycle, you can learn to tell the difference between what’s normal and what could be a sign of an underlying health issue. For this reason, we believe that all women should understand how to read their cycles, not just women who want to become pregnant.
There are a variety of tools you can use to track your cycle. Once you find a method that works for you, here are the three elements of a healthy cycle that you should be looking for:
A healthy menstrual cycle includes ovulation. In the first part of your cycle, the follicular phase, several follicles are maturing in your ovaries. One of them will mature faster than the others, and this one will release an egg. It takes roughly two weeks for the egg to mature, but this length of time can vary widely from woman to woman, and even in the same woman from cycle to cycle.
Stress, exercise, and diet can all impact ovulation, either by delaying it or preventing it. If you’re tracking your cycle, you might notice that you ovulated later than usual, or you didn’t ovulate at all. It’s normal for this to happen once or twice a year, and not cause for concern. But if you are consistently experiencing very long or anovulatory cycles, it’s a good idea to talk to a doctor and consider whether stress is affecting your cycle.
Why should you care about consistent ovulation? If you’re trying to get pregnant, that’s easy: it’s impossible to conceive without ovulating. But even if you’re not trying to conceive, ovulation is still an important health indicator. Ovulation tells you that you are experiencing estradiol and progesterone surges each month. These surges in hormone levels don’t just ensure your fertility—they are also required for building and maintaining your bone, keeping your brain healthy for the long term, and keeping your skin, hair, and nails looking healthy and lustrous.
2. A luteal phase of at least 10 days.
The luteal phase is the second part of your menstrual cycle, between ovulation and your period. It’s named after the corpus luteum, which is what’s left of the follicle where the egg was maturing before ovulation. The corpus luteum produces progesterone, which nourishes the uterine lining to prepare for a possible pregnancy. If the egg is not fertilized, the corpus luteum stops producing progesterone after about 10-16 days, and the uterine lining is shed during your period.
Unlike the follicular phase, which can vary widely and is sensitive to stress, the luteal phase generally doesn’t vary by more than a day in a particular woman. A luteal phase under 10 days can make it difficult to get pregnant, since the uterine lining sheds before a fertilized egg is able to implant. Stress, age, being over- or underweight, and exercise can sometimes lead to a shortened luteal phase.
Even if you’re not trying to conceive, the length of your luteal phase is still important, because it’s a good proxy for your progesterone levels. A short luteal phase is also a sign of low progesterone levels, which can have implications for bone health, among other things. (Other signs of low progesterone include spotting during your luteal phase and low basal body temperatures during your luteal phase.)
3. Menstrual bleeding that is not debilitatingly painful or prolonged
Menstrual bleeding varies widely from woman to woman. While the most common amount of menstrual flow is about two tablespoons during the whole period, the exact quantity can range from just a tiny spot to over two cups! Women who are taller, have had children, and are in perimenopause often have heavier flows. The normal length of bleeding is four to six days, and the normal amount of blood loss is 10 to 35 ml.
Heavy menstrual bleeding is usually treatable, but the treatment depends on the cause. There are many possible causes including polyps, endometriosis, fibroids, and even copper-containing IUDs. If you’re concerned about the amount you’re bleeding during your period, it’s worth bringing up with your health care provider. They will probably ask about the amount you’re bleeding. A fully soaked, regular-sized tampon or pad holds a teaspoon (5ml) of blood.
Whatever the cause, heavy bleeding can cause iron deficiency. Ask your doctor for a complete blood panel to test for anemia, and treat with iron supplementation if necessary.