Understanding Your Menstrual Cycle

By Stacey Colino

You're probably all too familiar with how your period affects your mood and cravings (hello, once-a-month chocolate fest!), but your period is just one part of your monthly menstrual cycle and a snapshot of how well your body is functioning. "Regular periods with no unusual symptoms mean your hormones are working properly, which bodes well for other parts of your body," explains Nanette Santoro, MD, professor and chair of obstetrics and gynecology at the University of Colorado at Denver.

On the other hand, irregular periods may mean that you don't have enough estrogen, a hormone that's essential not only to your reproductive system and fertility, but also to the health of your heart and bones. Too-low levels can affect your risk of heart disease, osteoporosis and even diabetes.

The important bottom line: All those hormonal changes your body goes through affect just about every aspect of your mental and physical health-for good and sometimes not-so-good. To help you understand it all, we've put together this comprehensive guide, starting with a rundown of what's really going on during your monthly cycle.

Days 1-5: Your Period!

The good: The worst of PMS is over. Levels of the hormones estrogen and progesterone drop, and some symptoms, especially breakouts, subside.

The not-so-good: You've got cramps and the crankies, and generally don't feel like yourself thanks to low hormone levels. The cramps are caused by chemicals called prostaglandins, which your body produces to prompt contractions in your uterus so the lining will shed. For some women, prostaglandins can also cause nausea, diarrhea, vomiting and even flu-like achiness, says Dr. Santoro.

Some studies have also revealed that reaction time may be longer (e.g., you may be slower to react when the car in front of you takes a sudden left turn), so be extra-cautious. And exercising may feel more strenuous than usual.

Who knew? "Many writers and artists have reported in their journals that they have more creative ideas during their periods," says Joan Chrisler, PhD, a professor of psychology at Connecticut College who has researched women's menstrual experiences.

Days 6-13: Feel-Great Days

The good: Estrogen levels start to rise as your ovaries gear up a "mature" egg for ovulation. This increases concentrations of feel-good brain chemicals, such as serotonin and dopamine, and enhances blood flow to the brain. You're likely to feel better mentally and perform better physically. One study found that swimmers have their fastest times on the eighth day of their cycles; other studies suggest that cross-country skiers perform better around now. This may be because estrogen helps your muscles better absorb glucose, a sugar in your blood that provides your body with fuel.

The not-so-good: Since your estrogen levels are rising, nothing negative to report here.

Who knew? You may be better able to read other people's facial expressions and emotional states during this phase.

Days 14-15: Pregnancy Alert

The good: Call it Mother Nature's way of making sure the species survives: Your sex drive is the highest the few days around ovulation, probably because this is when you're most fertile. "It's best to have sex within 24 hours of ovulation, since ideally you want the sperm to be waiting when the egg comes down," says Dr. Santoro. If you're using an ovulation kit and seeing high levels of luteinizing hormone (LH) in your urine, expect ovulation to happen about 36 hours later. So get busy! (Or not, if a baby's not in your plans.)

The not-so-good: Be careful while you're playing sports. Research has found that women's knee joints tend to be looser during ovulation, which could make you vulnerable to an anterior cruciate ligament (ACL) injury.

Who knew? Twenty percent of women can actually feel when they ovulate. They may get slight cramping called mittelschmerz, from the German for "middle pain."

Days 16-28: Prep for PMS

The good: Your body burns an extra 100 to 300 calories per day the week before your period, so if you've ever felt hungrier during that time, it's for a good reason. Try to get your fill of extra calories with healthy protein-carb combos, like 1 Tbsp of peanut butter on a whole-wheat pita, or a handful of nuts with a few whole-wheat pretzel sticks.

The not-so-good: An initial rise in progesterone can cause your skin to produce more oil, making you pimple-prone. As you get closer to your period, progesterone and estrogen levels drop, causing mood changes and concentration problems. About a week before your period, fatigue, cravings, breast tenderness and bloating get into full swing. In fact, water retention could cause a 3- to 5-pound gain. Cutting back on salt (it makes you retain water) and doing moderate exercise (which helps increase the production of feel-good endorphins) can ease symptoms, says Diana Taylor, RNP, PhD, director of the PMS Symptom Management Program at the University of California, San Francisco. Migraines can crop up just before-and during-your period because of the drop in estrogen. "We often give women who get migraines an estrogen patch for a day or two before their periods as a preventive measure," explains Diana Dell, MD, an assistant professor of psychiatry and obstetrics-gynecology at Duke University Medical Center.

Who knew? If you crave chocolate, it could be because it has magnesium, which you lose as estrogen levels start to dip.

Cycling Through the Decades

As you get older, your period, like the rest of your body, evolves. Here's what to expect.

In Your 20s

Your biggest concern is probably cramps, since they tend to be worse when you're younger. The culprit: the prostaglandins that your body produces to stimulate contractions in your uterus in order for the lining to shed, explains David Plourd, MD, an assistant professor of obstetrics and gynecology at the Naval Medical Center in San Diego. Head off pain by taking an anti-inflammatory like ibuprofen just before your period arrives or at the first sign of cramps.

In Your 30s

If you've had a baby, it can take 6 months or longer for your period to get back into a groove. Don't rely on breastfeeding as birth control unless you're doing it 100 percent exclusively; you can get pregnant even if your period hasn't come back. Fortunately, menstrual cramps usually ease up after childbirth.

By your late 30s your cycles may become shorter as fertility starts to drop off (the most dramatic decline is from ages 35 to 40). "Your cycles may go from, say, 30 days to 27," says Barry Witt, MD, medical director of the Greenwich Fertility Center in Connecticut.

Get bone health tips for every decade of your adult life.

In Your 40s

PMS can get worse and your periods may become unpredictable, thanks to hormonal changes as you inch closer to menopause, Dr. Plourd explains. You're less likely to ovulate, but don't ditch the birth control. "The second-highest unintended pregnancy rate is in women in their 40s," notes Dr. Plourd.

In Your 50s and Beyond

Chances are your periods are coming less frequently, if at all. Once you've gone a full year without one, you're officially in menopause (the average age is 51½). That means PMS symptoms are history! Birth control will also be a thing of the past, but if you have a new partner, don't forget condoms: The rate of STDs is increasing in people age 45 and older. If vaginal thinness and dryness becomes a problem, you can use try vaginal moisturizers and lubricants or vaginal estrogens, which thicken the vaginal wall to combat oversensitivity.

Photo: © Shutterstock


Original article appeared on WomansDay.com.


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