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PMS or Pregnant? How You Can Tell the Difference

Tender breasts? Mood swings? Exhaustion?

“Wait, am I getting my period, or am I pregnant?”

One of the most common  early signs of pregnancy is a missed period. But all women know, it isn’t that simple. There are a lot of subtle signs that could indicate it’s that ‘time of the month’ or that you’re pregnant—or even that something else may be going on.

“There are some distinct differences when it comes to pregnancy vs premenstrual syndrome or PMS symptoms, but some can be very subtle and can vary woman to woman,” said Robin Giles, a certified nurse practitioner with Banner – University Medicine North in Tucson, AZ.

Whether you’re anxious to have a baby or not, wondering can certainly be nerve-wracking. Here are some ways to help spot the differences and next steps on what to do.

PMS or pregnancy infographic

Similar symptoms of PMS and pregnancy

The signs and symptoms of PMS and early pregnancy can be similar but can vary from one woman to another. Some of the common related symptoms that women experience are:

  • Breast tenderness
  • Increased urination
  • Fatigue
  • Headaches
  • Constipation
  • Bloating
  • Mood changes
  • Food cravings

“Early pregnancy symptoms of breast tenderness and fatigue often mimic the symptoms of PMS,” Giles said. “However, breast tenderness and fatigue generally go away once your period starts.”

PMS-specific symptoms

PMS occurs in the second half of a woman’s cycle and can include physical, behavioral and emotional symptoms.

“Typically, women may have mild symptoms prior to the onset of their period each month, such as breast soreness (known as cyclical mastalgia), fatigue, bloating and decreased mood,” Giles said. “If your symptoms are more severe than that, it could be premenstrual dysphoric disorder, or PMDD, a more severe form of PMS.”

Pregnancy-specific symptoms

While your breasts may feel tender during PMS, they can be tender during the early stages of pregnancy as well. “You may also be pretty fatigued,” Giles added. “The key difference between the two, however, is that with pregnancy, your period doesn’t occur.”

Nausea and vomiting are symptoms that can accompany pregnancy and are often not experienced with PMS. “The nausea in early pregnancy often resolves after the 12th week of gestation,“ Giles said.

A sign your symptoms indicate something else

If you skip your cycle or have irregular periods and you’re not pregnant, there could be several other reasons. Some of the most common things to cause a change in the usual pattern can be fluctuations in your weight, hyper- or hypothyroidism, extreme stress and extreme exercise. Some hormonal methods of contraception can also affect your periods. There is a medical condition called polycystic ovarian syndrome, or PCOS, where women often stop getting their periods or have irregular cycles.

“It’s always a good idea to see your health care provider if you’re not having a regular monthly menstrual period,” Giles said. “We can do a workup for irregular cycles or for absence of menstrual cycles (amenorrhea) that may include a blood test and a pelvic ultrasound. It’s important to get treatment for amenorrhea or irregular cycles to prevent a condition known as endometrial hyperplasia. There are many treatment options to prevent this from happening.”

Next steps

If you’re not using birth control, are sexually active and your period is late or missed, it is advisable to do a home pregnancy test. If your test is negative, your doctor can help further investigate the cause for your symptoms. If your test is positive, make an appointment with your health care provider to confirm your pregnancy.

“Your provider will do a urine pregnancy test in the clinic and, if warranted, a blood test to detect the level of hCG (a pregnancy hormone),” Giles said. “It’s important that if you’re not using contraception and are sexually active that you take a prenatal vitamin, stop smoking and drinking and do not use any recreational drugs. Fetal development begins even before you may know you are pregnant.”

Schedule an appointment with an OBGYN near you.

For more helpful tips about your period and/or pregnancy, check out:

Women's Health Pregnancy Gynecology