There’s a lot more to a menstrual cycle than just a period and possibly a few days of feeling grouchy right before your period.
A menstrual cycle is a roughly four-week span of time when three key hormones—estrogen, testosterone and progesterone—rise and fall in a specific pattern.
Depending on how high or low these hormones go and the direction they’re headed, they impact you in a wide variety of ways, for instance your mood, energy, love life, spending habits, sleep quality, food cravings and health.
Why is this important information to know? Since your hormones follow a predictable pattern every cycle, it means the effects they have on you are the same cycle after cycle—and this allows you to know ahead of time what your moods, health and behavior will be.
As a result, it can help you plan your day, week and month ahead and enable you to take advantage of hormonal benefits (such as high-energy days) and overcome hormonal challenges (such as countering fatigue on low-energy days), making every day of your cycle better.
THE FEMALE HORMONE CYCLE
Below is a quick week-by-week guide that reveals a few of the many ways your hormones are impacting you throughout the four weeks of your cycle—spanning from the first day of your period through the day before your next period.
Day 1 (first day of period) to Day 7
During this week of your cycle, estrogen starts out at rock-bottom and begins a steady climb. Once you get past the achy, fatiguing part of your period, this rise in estrogen will be boosting your energy, mood, optimism and brain skills. It also makes you chattier and pushes you to connect with others both socially and romantically.
In general, you’ll find that as the level of your estrogen increases, you get a bit more curious about the world around you, want to have fun, enjoy shopping and prefer to be out of your home and among other people.
Rising estrogen also has a slight appetite-suppressing effect, which makes it a bit easier to eat smaller portions and opt for healthier foods throughout this week and the next week of your cycle.
Day 8 to ovulation (which is Day 14 in a 28-day cycle)
Estrogen and testosterone rise till they peak
Estrogen continues to rise throughout your Week 2, amping up all the positive effects you experienced during your Week 1. So, you’re likely to be more upbeat, optimistic, chattier and confident, plus have a sharper memory, think faster on your feet and fantasize about romance far more frequently.
The high level of this hormone is also making you more self-assured about your appearance. And, in fact, estrogen is actually boosting your attractiveness by prompting subtle shifts in soft tissue that make your facial features slightly more symmetrical.
High estrogen triggers a greater output of pain-masking endorphins in the brain, which means uncomfortable activities—like getting a tooth cavity filled or breaking in new shoes—will hurt less this week than during other weeks of your cycle.
While there are lots of benefits to enjoy about a high level of estrogen, there is one downside to be aware of: It can amp up anxiety, making you prone to stressing out over issues big and small.
One other hormone that’s key in your Week 2 is testosterone, which rises during the latter part of this week. When that happens, it tends to make you more impulsive, daring and competitive. It’s also prompting a sharp spike in your libido and makes your orgasms more intense and easier to achieve.
Begins the day after ovulation and lasts 8 days (Day 15 to Day 22 in a 28-day cycle)
Progesterone rises; estrogen and testosterone drop for half the week, then estrogen rises again
The first half of your Week 3 is your “pre-PMS” phase. The symptoms are like a shorter, less intense version of premenstrual syndrome (PMS): They may include irritability, fatigue and a down mood. Like PMS, pre-PMS is also caused by plunging estrogen. While most women are aware that estrogen plunges once in their cycle—in the days before their period—not many realize there are actually two estrogen dips every cycle. See the graph above.
Luckily, by the second half of your Week 3, estrogen rises again, putting a stop to any annoying pre-PMS symptoms you’ve experienced, which helps level out your mood.
Another important hormone in your Week 3 is progesterone. All throughout this week, progesterone rises—and this sedating hormone can make you sleepy, quiet, mentally foggy, less interested in socializing and more cautious. Progesterone is also reining in your libido and triggering cravings for ooey gooey comfort foods rich in sugar, fat and salt. If you’re sensitive to progesterone, this hormone can also make you a bit blue.
Final 6 days of your cycle
Estrogen and progesterone plunge
As estrogen plunges during this premenstrual week, it can trigger moodiness, sadness, irritability, muscle aches, insomnia, headaches, fatigue and a wide variety of other PMS-related symptoms. Not every woman suffers from premenstrual syndrome and symptoms can be milder or more severe from month to month often due to diet, stress, medications, exercise habits or your body’s personal sensitivity to hormones.
But, it’s not all bad news. In fact, this week your libido returns, though technically that’s not due to hormones. Researchers believe it’s because nerve endings down below get stimulated as your body prepares for menstruation.
Another upside of your premenstrual week is that you may notice you feel more energetic and clear-headed compared to how you were in your Week 3. That’s because progesterone is plunging—and that means there’s less of this sedating hormone to weigh you down physically and mentally.