Figuring out when you enter Week 1 of your monthly cycle is simple: It starts on the first day of your period, which is considered Day 1. This is when estrogen bottoms out, signaling your body to start shedding your uterine lining.
A few hours after your period begins, estrogen begins to slowly rise and it continues to rise throughout this week.
Depending on your sensitivity to rising estrogen, you may experience an improvement in mood, energy, memory and the desire to socialize within the first couple of days of your period starting thanks to this hormone. Or, it may take until the middle of your Week 1 for these hormone-fueled benefits to kick in.
Either way, you’ll notice that any premenstrual symptoms you may have experienced subside and you’re on the upswing mentally and physically.
You officially reach Week 2 of your cycle 8 days after start of your period. But, if you’ve lost track, look for these clues from your brain: You tend to have more upbeat moods, your memory is sharper, you’re thinking faster and are speaking more quickly and fluidly. You’re also more impulsive, confident and outgoing. These effects are all due to peaking estrogen and testosterone.
Your body is also making it easy to determine when you’ve reached Week 2: You have far more energy and stamina, you’re less sensitive to pain, your libido is revved and your vaginal secretions are clear and thin.
The last day of your Week 2 is the day you ovulate—and the day this occurs can vary according to the length of your cycle. Fortunately, there are a few easy tools to help you determine when you ovulate, which you can learn about by clicking here.
You officially enter Week 3 the day after you ovulate. In a 28-day cycle, that would be Day 15.
Not sure when you ovulated, but suspect it already happened? You can confirm it by looking for these clues: One to two days after you ovulate, you’ll likely feel slightly fatigued to downright lethargic, have intermittent irritability, be mental foggy or forgetful and have a significantly lower sex drive—basically the exact opposite of everything you experienced in your Week 2.
Why the many sudden changes? One reason is plunging estrogen. Very few women are aware that estrogen actually dips not once, but twice every month—and this is the first of those two plunges. As a result, you can experience a bit of “pre-PMS”, which is similar to what you experience during regular PMS, but shorter and less intense.
The other culprit triggering all these changes is progesterone. This sedating hormone rises all throughout Week 3, and as it climbs, it brings down your pep, quashes your libido and slows your brain speed.
Progesterone is also triggering a bigger appetite and cravings for sweet, salty and fat-rich comfort foods.
There’s one more clear-cut signal you can look for: Your vaginal discharge becomes thick and cloudy due to rising progesterone. So, a quick “dipstick” test can help you figure out if you’ve entered your Week 3.
Known best for being the week you might experience symptoms of premenstrual syndrome, you may realize you’re in your Week 4 by sudden bouts of irritability and moodiness, headaches, sadness, anxiety or a mix of all the above.
The 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.
There is one more silver lining to enjoy in your Week 4: Your libido comes back to life and gets more intense the closer you get to your period. This isn’t due to hormones, however. Instead, researchers think it’s a side effect of nerve endings down below getting stimulated as your body prepares for menstruation.
Please do not use the methods described above to detect ovulation as a sole method of birth control. Semen, a surprisingly patient male bodily secretion, can live within your body for up to seven days, which means if you have sex up to a week prior to ovulation, you could possibly get pregnant even if you abstain during ovulation.