You may experience period symptoms before your period starts as part of premenstrual syndrome. Symptoms can vary but may include cramps and breast tenderness.

Somewhere between 5 days and 2 weeks before your period starts, you may experience symptoms that let you know it’s coming. These symptoms are known as premenstrual syndrome (PMS).

More than 90 percent of people who menstruate experience PMS to some degree. For most, PMS symptoms are mild, but for others, symptoms can be severe enough to disrupt daily activities.

Symptoms vary from person to person, but paying attention to any unique patterns your body follows month to month can be a great way to catch the onset of each cycle.

If you have PMS symptoms that interfere with your ability to work, go to school, or enjoy your day, talk to your doctor.

Your period — and the PMS symptoms that can accompany it — is just one part of your monthly menstrual cycle. This cycle, which can vary in length from person to person or just over time, has four phases:

  • menstrual phase, when you get your period and may experience PMS
  • follicular phase, when your body creates the small sacs that can mature into eggs
  • ovulation phase, when a mature egg is released from the ovaries and travels to the uterus
  • luteal phase, when hormones prepare your uterine lining to host a fertilized egg

After the luteal phase, if the egg remains unfertilized, decreasing hormone levels restart the cycle, and the thickened uterine lining is shed as your period.

It’s normal to experience any of the following symptoms just before, during, or after your period.

1. Abdominal cramps

Abdominal, or menstrual, cramps are also called primary dysmenorrhea. They’re a common PMS symptom.

Abdominal cramps can start in the days leading up to your period and last for several days or longer once your period starts. The cramps may range in severity from dull, minor aches to extreme pain that stops you from participating in your usual activities.

Menstrual cramps are felt in the lower abdomen. The achy, cramping feeling may also radiate out toward your lower back and upper thighs.

The cramps are caused by uterine contractions, which help shed the inner lining of the uterus (endometrium) when a pregnancy doesn’t take place. The production of fatty-acid hormones called prostaglandins trigger these contractions. Although these lipids cause inflammation, they also help regulate ovulation and menstruation.

Some people experience their most intense cramping while their menstrual flow is at its heaviest.

Certain health conditions can make cramps more severe. Those include:

Cramps associated with these types of conditions are known as secondary dysmenorrhea.

2. Breakouts

Menstruation-related breakouts are fairly common. One study looking at a group of women found that around half noticed an increase in acne about a week before their period started.

These pre-period breakouts often erupt on the chin and jawline, but can appear anywhere on the face, back, or other areas of the body. The acne is caused by the natural hormonal changes associated with the female reproductive cycle.

If no pregnancy takes place when you ovulate, estrogen and progesterone levels decline while androgens, such as testosterone, increase slightly. The androgens in your system stimulate production of sebum, an oil produced by glands within the skin.

When too much sebum is produced, acne breakouts are a common result. Period-related acne often dissipates near the end of menstruation or shortly afterward when estrogen and progesterone levels start to climb.

3. Tender breasts

Progesterone levels start to rise in the middle of your cycle, around ovulation. This makes the mammary glands in your breasts enlarge and swell. These changes cause your breasts to get an achy, swollen feeling right before or during your period, even as progesterone levels lower once again.

This symptom may be slight for some. Others find their breasts become very heavy or lumpy, causing extreme discomfort.

4. Fatigue

As your period approaches, your body shifts gears from getting ready to sustain a pregnancy to getting ready to menstruate. Hormone levels plummet, and fatigue is often the result. Mood changes may also make you feel tired.

Some people who menstruate have trouble sleeping during this part of their cycle due to discomfort from other symptoms. Lack of sleep can exacerbate daytime fatigue.

5. Bloating

If your tummy feels heavy or it feels like you can’t get your jeans to zip up a few days before your period, you may have PMS bloating. Changes in estrogen and progesterone levels can cause your body to retain more water and salt than usual. That results in a bloated feeling.

The scale may also go up a pound or two, but PMS bloating isn’t permanent weight gain. Many people get relief from this symptom 2 to 3 days after their period starts. Often the worst bloating occurs on the day that bleeding begins.

6. Bowel issues

Since your bowels are sensitive to hormonal changes, you may experience alterations in your typical bathroom habits before and during your period.

The prostaglandins that cause uterine contractions to occur can also cause contractions to take place in the bowels, due to the close proximity of the organs. You may find you have more frequent bowel movements during menstruation. You might also experience:

  • diarrhea
  • nausea
  • gassiness
  • constipation

7. Headache

Since hormones are responsible for generating the pain response, it’s understandable that fluctuating hormonal levels might cause headaches and migraine to occur.

Serotonin is a neurotransmitter that often sets off migraine and headaches when its levels fluctuate. Estrogen may increase serotonin levels and the number of serotonin receptors in the brain at certain points during the menstrual cycle, setting off migraine attacks in those who are prone to them when the interplay reverses.

More than 50 percent of women who get migraine report an association between the occurrence of migraine and their period. Migraine attacks might occur before, during, or immediately following menstruation.

Some people also experience migraine attacks at the time of ovulation. A clinic-based study reported in Neurology found that migraines were 1.7 times more likely to occur 1 to 2 days before menstruation and 2.5 times more likely to occur during the first 3 days of menstruation.

8. Mood swings

The emotional symptoms of PMS can sometimes be more severe than the physical ones. You may experience:

  • mood swings
  • depression
  • irritability
  • anxiety

If you feel like you’re on an emotional roller coaster or feel sadder or crankier than usual, fluctuating estrogen and progesterone levels may be to blame.

Estrogen can affect production of serotonin and feel-good endorphins in the brain, decreasing feelings of well-being and increasing depression and irritability.

For some, progesterone may have a calming effect. When progesterone levels are low, this effect may be diminished. If you’ve ever found yourself crying for no reason while on your period, low progesterone is probably to blame.

9. Lower back pain

The uterine and abdominal contractions triggered by the release of prostaglandins may also cause muscle contractions to occur in the lower back.

An aching or pulling feeling may result. Some may have significant lower back pain during their period. Others experience mild discomfort or a nagging feeling in their back.

10. Trouble sleeping

PMS symptoms like cramps, headache, and mood swings can all affect sleep, making it harder to fall or stay asleep. Your body temperature, which can rise ever so slightly while on your period, may also make it harder for you to catch those much-needed Zzz’s.

Core body temperature rises about half a degree after ovulation and stays high until you start to menstruate or shortly after. That may not sound like much, but cooler body temps are associated with better sleep. That half a degree can impair your ability to rest comfortably.

Although PMS symptoms are far from fun, they’ll likely remain mild enough not to interfere with your day-to-day life in any major way. If you find yourself experiencing severe cramps, aches, fatigue, or any other symptoms that get in the way of things like work, school, or social plans, it may be time to consider visiting a doctor.

Severe mood swings that dip into panic attacks or suicidal thoughts are also important symptoms to address with a healthcare professional.

If you have severe symptoms, you may have premenstrual dysphoric disorder (PMDD). This is a more severe form of PMS. A doctor’s care may be the best treatment.

If you have severe migraines, you may also benefit from seeing your doctor. Underlying health issues, such as irritable bowel syndrome or endometriosis, might also make PMS more severe, requiring a doctor’s help.

The range and severity of your PMS symptoms will ultimately determine the treatment that’s best for you.

In some cases of PMS, your doctor might prescribe birth control pills to regulate your hormones. Birth control pills contain varying levels of synthetic types of estrogen and progesterone.

Birth control pills stop your body from naturally ovulating by delivering consistent and steady levels of hormones for three weeks. This is followed by one week of placebo pills, or pills that don’t have hormones. When you take the placebo pills, your hormonal levels fall so you can menstruate.

Because birth control pills provide a steady level of hormones, your body may not experience the plummeting lows or escalating highs that can cause PMS symptoms to occur. Other hormonal birth control methods, such as IUDs and implants, can also help regulate your period and may be recommended by your doctor.

You can often relieve mild PMS symptoms at home, too. Here are some tips to consider:

  • Reduce your salt intake to relieve bloating.
  • Take over-the-counter pain relievers, such as ibuprofen (Advil) or acetaminophen (Tylenol).
  • Use a hot-water bottle or warm heating pad on your abdomen or lower back to relieve cramps and soreness.
  • Exercise moderately to improve mood and potentially reduce cramping.
  • Eat small, frequent meals so your blood sugar remains stable. Low blood sugar can trigger a poor mood.
  • Meditate or do yoga to promote feelings of well-being.

If you find yourself struggling emotionally during your period, consider consulting a doctor. In moderate to severe cases of PMDD, cognitive behavioral therapy or medications such as SSRIs may be used to address associated anxiety and depression.

It’s very common to experience mild symptoms of PMS in the days leading up to your period. You can often find relief with at-home remedies.

But if your symptoms are severe enough to affect your ability to enjoy life or participate in your usual daily activities, talk to a doctor.

Read this article in Spanish.