From easier cramps to heavier flow to more PMS mood swings, here’s a breakdown of what to expect decade by decade—and when a change in your Periods cycle could be a sign of something serious.
We’re just guessing, but your period is probably not your favorite monthly event—especially when it comes on suddenly. It’s late one month, early the next; you’re used to a flow lasting four days, then it sticks around for a week. Cramps keep you from moving when you’re out of pain relievers, but once you’re stocked up on ibuprofen, you don’t feel a thing.
Changes in your menstrual cycle like this are difficult to predict and extremely inconvenient to deal with. But all we can say is that you should get used to them. Because your period will continue to adjust and evolve as you get older, thanks in part to normal age-related hormonal changes as well as experiences like pregnancy and perimenopause.
Here’s a better idea of what to expect in the coming years (as well as what could be an indication that something isn’t right).
In your 20s
If you spent most of your adolescent years dealing with an evil period (you know, the no-show kind that then made surprise appearances at the worst times), we have good news: your flow will most likely become more consistent at this point in your life.
Why is this so? According to Lauren Streicher, MD, a Chicago-based ob-gyn and author of Sex Rx-Hormones, Health, and Your Best Sex Ever, it is very common for young girls to not ovulate regularly. Your periods will be more erratic if you do not have regular ovulation. When your cycle evens out and becomes more or less monthly, you’ll begin to experience PMS, cramps, and breast tenderness.
It can be an unpleasant surprise if you aren’t used to dealing with these side effects every month.
Another significant menstrual change that occurs in your twenties is the introduction of birth control. Many women begin using hormonal contraception during this decade because they have a stable partner and are too preoccupied with their careers to consider having children.
Going on the pill will almost certainly cause changes in your normal flow. Consider lighter and more consistent periods, less cramping, and fewer PMS symptoms.
In fact, the pill (or another form of hormonal contraception, such as the hormonal IUD or Depo-Provera, the birth control shot) can cause your periods to stop completely. Birth control pills suppress ovulation, and without ovulation, there is no uterine lining buildup to shed. And there you have it! There is no flow.
In your 30s
According to Dr. Streicher, menstruation should be fairly predictable and consistent in this decade. Symptoms such as a sudden increase in flow or more intense cramping than usual may indicate a larger problem. Fibroids, which are benign growths that can cause heavy bleeding, usually don’t appear until you’re in your 30s, for example.
Endometriosis, which is often characterized by excruciating pain that can last all month, is also frequently diagnosed in women in their 30s.
Another game-changer that could occur in your 30s? Having children. You’re well aware that becoming pregnant causes your flow to disappear. However, you may not be aware that if you are not breastfeeding, your period does not usually return until six weeks after delivery, that is all there is to it. If you choose to breastfeed, your period will not return until you stop or reduce the number of times you nurse.
Furthermore, having a child may cause long-term changes in your cycle. “Many women will tell you that their cramps improve after they have gone through pregnancy,” says Dr. Streicher. “That can be caused by a variety of factors, but as the cervical opening expands, the flow comes out without requiring as strong uterine contractions.”
In your 40s
This is where the real fun begins. Premenopausal hormonal fluctuations, which precede menopause, begin in your forties. During this time, usually eight to ten years before menopause (which occurs in your early 50s), your body prepares for the end of menstruation.
Ovulation becomes more irregular as a result of normal hormone changes, and fluctuating estrogen levels may result in missed periods, heavier flow, spotting between periods, and longer stretches of PMS. “The one thing that is predictable about perimenopause symptoms is that nothing is predictable,” says Dr. Streicher. Remember that even if your ovulation is irregular, you can still become pregnant. A woman is not considered to be in menopause until her periods have been irregular for at least a year.
Whatever your age, keep in mind that your period provides a wealth of information about your overall health. Dr. Ross advises that if you have any unusual symptoms, you should consult with your doctor. Extremely irregular periods or drastic changes in your flow may indicate thyroid problems, polycystic ovarian syndrome, or a variety of other (treatable) health issues.