28 Days Or 40? Here's How Long Your Cycle Is Really Supposed To Be
When it comes to menstrual cycles, figuring what's "normal" is really about what's normal for you. Despite what many of us have been told, the reality is that a person's menstrual cycle doesn’t always fit into a neat and tidy 28-day rotation. So, if your cycle tends to be 25 or even 40 days, don't worry—just keep track of your own cycle and the symptoms that may ebb and flow each month.
The good news? We now have medical insight into the phases of the cycle, so understanding your "normal" can help explain any shifts in your mood or energy.
What every woman should know about her hormone cycle.
The menstrual cycle is the hormonal process a woman’s body goes through each month to prepare for a possible pregnancy. Typically, the menstrual cycle occurs in the years between puberty and menopause, and the presence of your cycle means that your health and hormones are in alignment. There are four main phases of the menstrual cycle, and each presents its own shift in energy, mood, and vitality. If you pay close attention by tracking your cycle, you’ll begin to notice what helps you feel vital and balanced throughout each phase.
The follicular phase:
A woman's menstrual cycle starts with the follicular stage, which is the time frame before a woman ovulates. During this seven- to 10-day phase as the body prepares for ovulation, follicular stimulating hormone (FSH) rises to tell the ovaries to prepare to release an egg. The hormone estrogen, which is at its lowest level at this point in the cycle, also slowly begins to rise. While these hormones are beginning to rev up for the month, it's common to see increased energy and possibly even restlessness.
The release of an egg begins the ovulatory phase. The egg travels from the ovary to the fallopian tube where it awaits potential fertilization, which means this is the phase of the month when a women can get pregnant. FSH continues to rise, and luteinizing hormone (LH) levels increase. Estrogen levels reach their peak, and testosterone surges, and with these changes come an increase in libido and sexual energy.
With higher levels of both estrogen and testosterone, it's normal for a woman to feel naturally more positive, body confident, and yearning for a greater and deeper sense of connection and communication. And based on the shifts in hormones, that makes a lot of sense.
The luteal phase:
In the next phase, the luteal phase, the hormone progesterone rises, and as it does, premenstrual symptoms (PMS) like bloating, irritability, mood swings, and brain fog may develop for some women. These changes are partly due to the increase in progesterone, which boosts appetite and cravings for comfort food. Many women report an urge to retreat during this phase versus communicate, as commonly seen in the ovulation phase. It's a great time for some extra self-care.
The final stage of the menstrual cycle is the most well-known of all: the woman’s period. During the menstrual phase, progesterone production drops off and estrogen peaks and then drops. By nature, menstruation involves the intense process of eliminating the lining of the uterus. To help with any pain or cramps if you experience them, embrace your anti-inflammatory foods like leafy greens, cruciferous vegetables, and the powerful turmeric spice.
Your lifestyle can affect your cycle length. Here's what to do about it.
The length of the cycle does matter to some extent—for example, if your cycle length changes it's something to mention to your doctor—but it doesn’t have to be exactly 28 days for you to be in great hormonal health. It is common for women to have cycles every 25 to 40 days, and sometimes they vary in how heavy or light they present. Stress and extreme exercise intensity can often cause women to experience a flare-up in PMS symptoms like bloating, cramps, and energy fluctuations.
It's really helpful to monitor your cycle by using a smartphone application to track the length of your cycle and any other ongoing changes. Your monthly cycle can be thrown off by stress, antibiotics, illness, alcohol consumption, and too much exercise—all of which have the ability to delay ovulation.
1. Not getting enough sleep
Lack of sleep is a significant contributing factor to hormone imbalance. When our sleep schedule is off, or we simply aren’t getting enough of it, our bodies experience fatigue and stress, which dampens our ability to regulate the hormones necessary for proper energy, brain function, and vitality.
Too much strenuous exercise can contribute to weight loss, which impairs the body’s ability to have a regular cycle. Professional athletes like gymnasts, runners, and swimmers, who tend to have a lower body fat percentage, often experience disruptions in their cycle for extended periods of time.
Travel can affect a woman’s cycle, especially when there is a change in time zones. Being in a new time zone can affect sleep, brain function, and ultimately hormone health.
4. High cortisol levels
Continuous stress raises cortisol, the stress hormone. Cortisol increases inflammation in the body and can affect progesterone and estrogen balance.
Menstrual cycle symptoms that should be monitored.
If every woman's menstrual cycle is a different length and intensity, how do you know what's normal when it comes to period symptoms? Again, this is really more about what's normal for you, but there are a few symptoms to monitor closely. For starters, cramps and mood swings aren’t a rite of passage for women’s health, they are warning signs that there is some hormonal imbalance at play. You don’t have to stay curled up in bed with a heating pad counting down the hours and days until the pain subsides and the brain fog lifts. Painful periods are something to watch out for. If the pain impairs your ability to go to work and be social, you should consult with your physician.
Passing blood clots during menstruation can be normal, but it does depend on the amount and frequency for each woman. If the clotting is becoming extreme, it's worth checking with your physician about ruling out anemia and even dysmenorrhea. Mood swings can be hard for you and for those around you, but they don’t have to be the norm. During the luteal phase, when progesterone rises and estrogen dips, mood swings are more common, but if they are severe, see your doctor.
A healthy cycle length is all about knowing what's normal for you and paying attention if or when signs and symptoms change. So listen closely to what your body is asking for; embrace regular stress management techniques; consume high-quality whole foods; and ensure adequate sleep to increase your chances of achieving optimal hormonal balance.
Want to gain some more hormone knowledge? Take our Ultimate Guide to Healthy Periods class with Alissa Vitti.
Robin Berzin, M.D., is a functional medicine physician and the founder of Parsley Health. She currently lives in New York, NY and her mission is to make functional medicine affordable and modern, so more people can access a holistic, root-cause approach to health.
A Summa Cum Laude graduate of the University of Pennsylvania, Dr. Berzin went to medical school at Columbia University and later trained in internal medicine at Mount Sinai Hospital. She is also a certified yoga instructor and a meditation teacher, and has formally studied Ayurveda. Dr. Berzin writes for a number of leading wellness sites, and speaks regularly for organizations including the Clinton Foundation, Health 2.0, Summit and the Functional Forum, on how we can reinvent health care.
She's also a mindbodygreen courses instructor, teaching her Stress Solution program designed to help you tune down the stress in your life and tune up your energy and happiness.