For a lot of women, premenstrual syndrome (PMS) and early pregnancy can produce similar symptoms and wondering if you are pregnant or not can be a nerve-wracking time. However, there are differences to help you differentiate between the two.  

Read on to learn the 10 biggest differences between PMS symptoms and pregnancy symptoms.    

1. Differences in Breast Tenderness During PMS vs Pregnancy

During the second half of the menstrual cycle, women can experience breast tenderness and a feeling of fuller or heavier breasts as the body produces more progesterone and less estrogen. However, breast tenderness usually disappears once menstruation beings and hormone levels are rebalanced.  

In the early stages of pregnancy, the breasts also become tender and fuller. This typically happens 10-14 days after conception and can last for up to a few months as the body produces more progesterone to sustain the pregnancy. 

2. Bleeding During PMS vs Pregnancy

Women generally do not experience any bleeding during PMS. 

For some women though, light bleeding or spotting for one or two days is normal in the 10-14 days after conceiving. If any heavy bleeding occurs during pregnancy or spotting continues for more than 2 days, it’s best to schedule an appointment with a doctor. 

3. Cramping During PMS vs Pregnancy

Cramping is a normal symptom of PMS, usually occurring a day or two before menstruation. The pain generally decreases as soon as menstruation begins and disappears completely by the end of a woman’s period. 

During early pregnancy, some women can experience light cramping in the lower belly or lower back. For some, the cramps will last for weeks, sometimes months into the pregnancy. Rest will normally ease the pain. However, if the cramps coincide with any bleeding, it is best to consult with a doctor. 

4. Mood Swings During PMS vs Pregnancy 

Feeling irritable, a little anxious, and a bit grumpy during PMS is perfectly normal. Once again, this is due to the hormonal fluctuations that happen during the menstrual cycle. Women’s moods generally return to normal after menstruation begins.  

When pregnant, women are more emotional. This is mainly due to the anticipation and excitement, as well as the hormonal changes that occur during each trimester. One day may bring happiness and joy, while other days can feel sad and overwhelming. These mood changes are very common and will usually last right up until giving birth. 

Exercise and sleep can help to relieve mood swings during both PMS and pregnancy. If however, you experience prolonged feelings of sadness, anxiety, or hopelessness – for more than two weeks – pay a visit to your doctor to discuss treatment.   

5. Differences in Food Cravings During PMS vs Pregnancy

PMS can cause a change in women’s diets in the form of cravings for carbohydrates, sugar, and salty foods. This is mainly due to drops and spikes in hormones like serotonin and cortisol, as well as blood sugar levels. The good news is the cravings usually subside as menstruation comes to an end.  

Pregnancy cravings and aversions to certain foods are also the results of hormonal changes. Nutritional deficiencies can contribute to pregnancy cravings too, such as pickles for low sodium, lemons for vitamin C, or ice cream and yogurt for low calcium. 

In addition, a heightened sense of smell and taste while pregnant can cause food cravings. But they just as easily lead to an aversion to, or an avoidance of, certain foods.  

Should pregnant women experience cravings for non-food items such as dirt, metal, flakes of paint, or crayons, it is best to schedule an appointment with a healthcare provider. These cravings may be due to a deficiency in iron, or zinc and could cause anemia in pregnant women. 

6. Increased Urination During PMS vs Pregnancy 

Once again, it is the fluctuations of hormones that cause an increase in urination during PMS. Although not exactly understood by researchers, the increased urge to pee during PMS is thought to be caused by the drop in the production of progesterone. It will, however, ease back to normal as menstruation progresses.  

On the other hand, frequent urination is very common during each stage of pregnancy. In the first trimester, it is more commonly caused by hormonal changes. During the second trimester, your baby pressing against your bladder can cause you to pee more. And in the last few weeks, when there is more pressure on the pelvic floor muscles, it is perfectly normal to experience a little bladder leak when coughing or sneezing.  

7. Fatigue During PMS vs Pregnancy

Feeling tired or fatigued is perfectly normal during PMS due to the hormonal changes occurring in the body. Even though you might not feel like it, gentle exercise like yoga can help increase energy levels. And once menstruation begins, PMS fatigue generally begins to subside. 

When pregnant, an increase in the production of progesterone causes fatigue in expectant moms, especially during the first trimester. Although some can feel fatigued throughout the pregnancy,  tiredness usually fades during the second trimester. Feeling fatigued again just before the birth is perfectly normal due to the extra weight and pressure on the mom’s body.  

Eating a nutritious diet and getting plenty of rest helps to relieve pregnancy fatigue. 

8. Sleep Disturbances During PMS vs Pregnancy

While researchers don’t completely comprehend why PMS affects sleep, it is believed to stem from the changing levels of hormones like progesterone and serotonin.  A drop in melatonin, which is linked to the regulation of the circadian rhythm, is also thought to result in disruptions to regular sleep patterns during PMS.

Similarly, many women experience sleep disturbances during pregnancy due to hormonal changes. However, physical discomfort, as well as the excitement and anxiety that come with being an expectant mom also contribute to interrupted sleep. 

Nausea, increased heart rate, nasal congestion, more frequent night-time urination, and restless legs can also contribute to sleep disturbances during pregnancy.  

9. Nausea During PMS vs Pregnancy

While nausea is not a common symptom of PMS, some women can experience nausea related to digestive problems during this time of the month. 

During the first trimester of pregnancy, usually a month after conceiving, many women experience bouts of nausea known as Morning Sickness. This is commonly caused by the sudden increase of hormones. And although the name suggests it occurs in the morning, it can happen at any time of the day. 

For most expectant moms, morning sickness eases off during the second trimester. Some never experience nausea. And others can suffer from a condition called Hyperemesis Gravidarum, which is a severe case of morning sickness throughout their pregnancy. 

10. Headaches During PMS vs Pregnancy

The drop in estrogen levels before menstruation is believed to contribute to headaches during PMS. However, they usually disappear with the onset of menstruation. 

When pregnant, changing hormone levels along with the rise in blood volume during the first trimester can cause headaches.  Other known causes of pregnancy headaches are fatigue and eyestrain, as well as nasal congestion. Dehydration and poor sleep are also culprits. And some pregnant women can suffer from headaches after giving up caffeine.   


PMS and early pregnancy symptoms can be quite similar, however, there are noticeable differences too. Understanding and tracking your normal PMS symptoms can significantly help in determining the difference between the two. 

If pregnant, it is always better to know sooner rather than later to ensure that proper care is taken. Taking a pregnancy test, or scheduling an appointment with your doctor, is the best way to determine if you are experiencing PMS or pregnancy symptoms.     


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Science Direct/Sleep Medicine - Objective sleep interruption and reproductive hormone dynamics in the menstrual cycle -

National Center for Biotechnology Information - Sleep Disturbances During Pregnancy

Mayo Clinic - Pregnancy week by week -

Mayo Clinic Staff - Symptoms of pregnancy: What happens first -

The American College of Obstetricians & Gynecologists - Morning sickness: Nausea and vomiting of pregnancy -

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