PMS vs. Pregnancy Quick Comparison of Differences
Symptoms and signs of PMS may be similar to those of early pregnancy.
- Symptoms of early pregnancy can be similar to those experienced by women just prior to the menstrual period.
- At times, it can be confusing to distinguish between early pregnancy and an approaching menstrual period. Women wonder if they may have period symptoms while they are actually pregnant or they may be unsure if they can tell the difference between the cramps of PMS or an early pregnancy.
- True menstrual bleeding does not occur in pregnancy, although many women experience some light bleeding during the first weeks of pregnancy. In particular, light bleeding around the time of implantation of the fertilized egg is common and occurs at about the time of the expected period.
- Common symptoms of PMS and early pregnancy include breast swelling, enlargement, pain, discomfort, or tenderness.
- Early pregnancy symptoms like nausea and vomiting are not common in PMS.
- The only way to tell if you are pregnant is to take a pregnancy test if your period is late or absent.
What Is Premenstrual Syndrome (PMS)?
Premenstrual syndrome (PMS) is a set of symptoms that occur prior to the menstrual period. Symptoms of PMS begin anytime in the two weeks prior to the onset of menstrual bleeding. Premenstrual dysphoric disorder (PMDD) is a severe form of PMS that occurs in a small number of women. These women have more severe and disabling symptoms.
PMS Symptoms and Early Pregnancy Symptoms Comparisons
Is it just my period or am I pregnant? This is a common question for many women since certain signs and symptoms of early pregnancy can be similar to those of premenstrual syndrome. Similar signs and symptoms of pregnancy and PMS include:
- Weight gain
- Enlarged, swollen, and painful, or tender breasts
- Mood swings or changes like
- Mild abdominal cramping
- Back pain
- Weight gain
- Mood changes or emotional symptoms, for example:
Nothing can relieve the symptoms of morning sickness.
Which PMS and Early Pregnancy Signs and Symptoms Are Different?
The signs and symptoms of both pregnancy and PMS can be similar and somewhat nonspecific.
- The bleeding of a menstrual period, however, usually is different from that experienced by some women in early pregnancy.
- The bleeding of early pregnancy rarely is as heavy or lengthy as with the typical period. Most bleeding in pregnancy will be less heavy (not enough to soak a tampon or pad), and often is lighter in color or brownish.
- Implantation bleeding usually is light bleeding or spotting that occurs at the time the fertilized egg implants into the uterine wall. This bleeding takes place around the time of the expected menstrual period so it may be confusing for some women to tell the difference between implantation bleeding and menstrual bleeding.
- The cramping of PMS usually is more severe than cramping women experience early in pregnancy.
- Nausea and vomiting are more common in early pregnancy than in PMS.
- Some women with PMS have food cravings (or food aversions); however, they are more common in pregnancy.
- A white or milky vaginal discharge and darkening of the nipples and/or areolas are signs of early pregnancy that do not occur in premenstrual syndrome.
- Other signs and symptoms of PMS can include that do not occur in early pregnancy include:
- For the most part, symptoms of PMS are predictable for a given woman and occur in regular intervals related to the timing of the menstrual cycle.
Can I Have My Period and Be Pregnant?
No, a true menstrual period represents the shedding of the uterine lining in preparation for a new menstrual cycle, and this does not occur in pregnancy. However, as described previously, many women have some degree of bleeding during the early weeks of pregnancy, such as implantation bleeding; that they mistakenly believe is due to a menstrual period. Such bleeding in early pregnancy is typically lighter than that of a true period.
A pregnancy test is the best and only definitive way to tell if you are pregnant.
United States. NIH. "What are some common signs of pregnancy?" Jan 31, 2017. <https://www.nichd.nih.gov/health/topics/pregnancy/conditioninfo/signs>.