While it may feel like an isolated event that happens for a few days each month, there is so much that goes into your period. And your menstrual health is a major component of your overall health, which includes diet, lifestyle, and stress too. “We call your period the fifth vital sign—and any irregularities give us an idea of the big picture quality of your health,” says Annie Shaltz, NP , a nurse practitioner at Parsley Health Los Angeles. It’s important to pay attention to your cycle each month (Shaltz recommends keeping track of your own data on an app on your phone or any calendar that works for you) to understand your own normal symptoms, whether it’s spotting mid-cycle, breast tenderness, heavy flow, or mood changes. That way, when something is different from your normal, you can talk about it with your healthcare provider.
Having a “normal” period depends on the person. While everyone’s period will be different, there are a few factors that come into play when evaluating your period health, including length, regularity, and flow. Your cycle can vary anywhere from 21 to 35 days and still be considered “regular” and bleeding anywhere from 3 to 7 days is common. If you experience prolonged bleeding, it could be a signal that you’re not ovulating regularly. Light periods, on the other hand, can be normal for some, including those that have a Mirena IUD.
When you think about your cycle, you may focus on exactly when the bleeding starts every month. But actually, Shaltz points out, there’s a lot that goes on to before you get to that part of your cycle—and a lot of things can influence it along the way.
In an average period cycle, the process first begins with gonadotropin-releasing hormone (GnRH) being secreted from the hypothalamus in your brain, which then stimulates the pituitary gland to release follicle-stimulating hormone (FSH), explains Shaltz. FSH acts at the ovaries to influence the developing follicle. It also causes estrogen to rise, which thickens the endometrium, preparing for an egg to implant. This is called the follicular phase and ends when the egg is released from your ovary (also called ovulation).
After that, there’s a 10 to 16 day period called the luteal phase in which a gland called the corpus luteum forms from the follicle that released the egg (yes, your body creates its own gland every single month), Shaltz explains. The corpus luteum releases progesterone and prepares your body for pregnancy. If pregnancy doesn’t happen, the uterine lining will shed, and your period begins.
Believe it or not, it takes 100 days for the egg follicle that is released during ovulation to fully develop in the ovaries. Everything else that happens during those 100 days of development of the follicle is crucial to having a healthy cycle too, Shaltz explains (to put it into perspective, the egg you release this month has been developing for three months—and think about everything that’s happened in the world since then). That means eating a balanced diet, sleeping well, and managing stress are all major factors in keeping this complicated dance of hormones in sync.
When you’re not ovulating (i.e. if you’re on hormonal birth control ), or have PCOS (a condition known for excess male hormones), you might have a higher ratio of estrogen to progesterone, which can affect other areas of your health, like your digestion, for example, if your body is not able to detoxify estrogen properly. Here are some signals your period can tell you about your overall health.
It’s true that your cycle can vary from 21 to 35 days, but any cycle shorter than 21 days or any cycle longer than 35 days is a red flag. If your period isn’t coming to kick off your cycle between those days, something isn’t right. “Anyone who is regularly irregular should consult their health care provider,” Shaltz says. Not getting your period within that 21 to 35 day time frame could in some cases mean that you’re not ovulating regularly, so it can affect your fertility .
One potential reason for irregular periods is thyroid health disorders, because the imbalance (either overproduction or underproduction of thyroid hormones) could mean that your estrogen levels are out of whack. Having severe PMS symptoms , along with irregularity in your cycle, could be an indicator that you have a thyroid condition affecting your period, Shaltz says.
But lifestyle factors, like sleep , can also affect irregularity. Research has confirmed that shift and service workers, for example, have irregular periods more frequently than people with other occupations. Because they might not be sleeping regular hours, their natural circadian rhythms can be impacted, which also affects menstrual cycle regularity.
Common reasons for missed periods include being underweight, at a very high level of stress, or even being an endurance athlete. (For example, some high-performance athletes like marathon runners may not get a period, because the physical demand causes physical stress that taxes the body and the body can’t do everything, Shaltz says). If you’ve recently gone on or off of birth control, keep in mind that your body takes time to adjust to being on birth control and being off of the pill . If you decide to get off of it—depending on your overall health, it can take anywhere from one to three months to six months to a year for your body to return to a normal period cycle.
Aside from that, on a rare occasion, there could be something wrong with your pituitary gland, a gland in your brain. It may not be producing certain hormones like FSH, or follicle stimulating hormone, that allows the eggs to develop in the ovaries, jump-starting the ovulation process.
If you’ve lost your period for longer than 7 to 14 days, Shaltz says, it’s a good idea to contact your healthcare provider, if your cycle is typically regular. It could mean you might be pregnant (in that case, start with a home pregnancy test). But even if you have no intentions of becoming pregnant, missed periods or changes in the length of your cycle can be a sign of something else wrong with your health, like PCOS or a thyroid condition.
Typically during menstruation, women lose about 50 milliliters of blood; if you’re losing more than about 80 milliliters of blood, that’s a problem, Shaltz says. According to the CDC , that would mean soaking through a pad or tampon (of the appropriate size) in less than two hours. Having good period health should mean that you’ll likely be dealing with 10 to 16 fully soaked regular tampons, or 5 to 8 fully soaked super tampons, explains Shaltz. An abnormally heavy period flow could mean that you have excess estrogen, so your hormone balance is off leading to a thicker uterine lining . It could be that you’re not ovulating regularly to make enough progesterone. Or, your body might not be properly detoxifying estrogen through your digestion—your body needs plenty of B vitamins, zinc, folate, selenium, and magnesium to do so, Shaltz says. If you’re not getting enough of those vitamins and minerals in your diet, it could affect your body’s ability to detoxify and remove estrogen and therefore, impact your cycle.
Excessively painful periods could be happening because of endometriosis , which is also linked to an imbalance of estrogen, or poor detoxification of estrogen, research has found. Again, deficiencies in your diet could be at play here. Shaltz recommends getting enough magnesium and omega-3 fatty acids for painful period cramps, because magnesium can relax the muscles and the nerves while omegas can reduce inflammation , thereby reducing pain. Talk to your provider to understand if you may need to supplement with magnesium or omegas.
Pay specific attention if you’re spotting in between periods. For some women, it’s normal to spot when you ovulate or the days leading up to your period. If you’ve been trying to get pregnant, or even if you haven’t, spotting could be a sign of implantation bleeding when pregnancy occurs, or an ectopic pregnancy, the condition in which a fertilized egg implants in the fallopian tubes instead of the uterus, Shaltz says. It can also happen due to uterine fibroids.
Or, if you’re taking a progestin-only hormonal IUD, it’s common to spot, even for a couple of months, Shaltz adds. But, Shaltz says, track the changes from one cycle to the next, including the color of the blood (it’ll likely be dark brown or bright red in color during spotting). If spotting isn’t typical for you, and it’s just happening once, then it’s a good idea to contact your healthcare provider to check and make sure everything else is fine.
After you give birth , it can take a while for your cycle to return to what it was like pre-pregnancy. First of all, you’re going to bleed after birth, for about three to four weeks after delivering, regardless of whether you had a vaginal birth or C-section. Though it may feel similar to menstrual cramps, this is not your period, Shaltz says; it’s actually the uterus returning to its normal shape and size, shedding the excess blood and tissue.
It varies from person to person how much and exactly how long you will bleed after giving birth. Right after giving birth, it’s common to pass larger clots, but if you notice a clot larger than a golf ball, you should report that to your OB/GYN or midwife, Shaltz says.
If you are breastfeeding after giving birth it might take a while for you to start ovulating again because Prolactin, the hormone that supports milk production, suppresses FSH, the hormone that stimulates your ovaries to develop a follicle.
Mara is a freelance journalist whose print and digital work has appeared in Shape, Brit+Co, Marie Claire, Prevention, and other wellness outlets.
Most recently, she was a member of the founding team of Bumble Mag, a branded content project for Bumble at Hearst Corporation. She enjoys covering everything from women's health topics and politics to travel. She has a degree in Communications as well as Italian Studies from Fordham University.