Premenstrual syndrome (PMS) and early pregnancy symptoms can look very similar. So similar, in fact, that it can be confusing to understand what your body is telling you. Both involve a complex interplay between the female reproductive organs and hormonal shifts. So PMS vs. pregnancy...is it possible to know which is which?

I missed my period

I can still remember the beginning of my fourth pregnancy like it was yesterday. My husband and I were not planning on welcoming any more children for at least a couple years. We were already managing a toddler, a 6-month-old, and had experienced a miscarriage. That was plenty for the time being.

Christmas had just passed, and I was officially done breastfeeding our daughter. I was excited to lose the rest of my baby weight, get in shape, and feel like myself again.

At the same time, our daughter was going through a growth spurt, cutting four teeth, enduring an ear infection, and having a difficult time sleeping at night. On top of this, I was managing ongoing medical care for our special needs toddler. Needless to say, I was a stressed, exhausted mama!

So when I missed my period, I was shocked and deeply distressed. We had been careful —there was no way we could be pregnant. I told myself it was delayed due to stress and sleep deprivation. I even googled my theory, but learned early signs of pregnancy, PMS symptoms, and even the effects of stress can all have things in common.

I was in denial

I told myself my body was adjusting to life’s current season: overwhelm, lack of sleep, no longer breastfeeding. But deep down in my gut, I knew I was pregnant. A mother’s intuition is rarely wrong. I just didn't want to admit it.

As I continued to delay my doctor’s appointment, I started experiencing some unmistakable early pregnancy symptoms.

I was exhausted, even considering my daughter’s poor sleep patterns. I was suddenly incredibly hungry, even compared to being on my period. If I didn't eat small, protein-rich snacks every couple hours, my body felt like it was starting to shut down, and I couldn't think or function normally. I was starting to get light-headed and a little nauseous. Breast changes started occurring too, and my usual pregnancy-related nasal congestion was coming back.

I finally admitted to myself I needed to see a doctor, but I was sure we would be talking about self-care and stress. Instead, when she walked into the room, she announced, "Congratulations, you're pregnant!”

PMS vs. Pregnancy Symptoms Chart

Pregnancy: the common early symptoms

The most immediate indicator of potential pregnancy is a missed period. But if your menstrual cycles aren’t always regular, this can be confusing too! Here are other common symptoms you may notice if you are pregnant:

Light bleeding

Maybe it looks like you've started and ended your period, but you're confused because it was much lighter than normal. It's possible that bleeding wasn't your period at all. Light bleeding or spotting can happen within two weeks after fertilization when the zygote (fertilized egg) implants in the uterine lining, often referred to as implantation bleeding.6

Breast tenderness/heaviness

A common symptom of both PMS and early pregnancy is sore, tender breasts. During pregnancy, breast pain is usually heightened and long-lasting. Your breasts themselves may feel larger and heavier. This will continue throughout the duration of pregnancy.6

Nipple changes

Other breast changes begin during early pregnancy that do not accompany PMS, like nipple changes. The colored area around your nipple, or areola, gets darker and larger. Many of these changes are caused by hormonal shifts in your body and serve to aid in breastfeeding down the road.6

Fatigue

Another common PMS symptom exaggerated in pregnancy is fatigue. Thanks to a hormone called progesterone, fatigue can be even worse in early pregnancy than what is typically experienced before your period. While PMS-related fatigue will go away in about a week, feeling exceptionally tired when you're pregnant can last for several weeks or months. Some women will experience it throughout their entire first trimester, or about 13 weeks.3

Bloating

If your usual PMS-related bloating is sticking around longer than normal, it could be a sign of pregnancy.4

Food cravings and aversions

Both PMS and pregnancy can cause some intense carb cravings. But during early pregnancy, there are other food-related symptoms. In pregnancy, a woman can simultaneously experience strong cravings and aversions. These new aversions to smells and food, even foods that were your favorite before pregnancy, are also due to hormonal changes.3

Nausea

While your body is figuring out what it will and won't tolerate, you might experience some nausea and possible vomiting, but they don’t always occur together. Some women only experience nausea or lightheadedness throughout the first trimester. You can even feel sick at the mere thought or sight of a particular food, or because you haven’t eaten and need some fuel.

Vomiting

While some women only feel nauseous, others will experience vomiting as well. But the stereotypical “morning sickness” attributed to early pregnancy is not only possible in the morning. It can happen at any time of the day, though most often in the morning or evening. Vomiting is more commonly associated with pregnancy and is not typically related to PMS.6

Pregnancy: the surprising early symptoms

Besides the more common symptoms of early pregnancy, you might be experiencing some rather unusual early pregnancy symptoms. Here are some additional signs of pregnancy you may not realize are related:

Nasal congestion

If your nose is congested like you have bad allergies or a weird cold, it's possible you're actually experiencing changes in blood volume and hormones related to pregnancy.5

Frequent urination

This is due to hormonal changes that trigger your need to urinate. Many people associate this symptom with late pregnancy, when the growing baby puts pressure on the bladder, but a hormone called human chorionic gonadotropin, or hCG, creates an increased need to visit the bathroom from the beginning of pregnancy. HCG is the hormone a pregnancy test is designed to detect.1

Milky-white vaginal discharge

Due to an increase in blood flow and estrogen production (a hormone that regulates the female reproductive system) you may see more vaginal discharge when you wipe. Increased discharge is present to help prevent infections in your cervix and vaginal area. It is often sticky and white or pale-yellow in color.5

Every pregnancy is different

Every woman and every pregnancy is different. With each of my four pregnancies I have experienced various levels of nausea, some vomiting, cravings, food aversions, breast changes, nasal congestion, a stronger gag reflex, occasional headaches, and being overwhelmingly tired.

Listen to your body

Understanding what your body is telling you is incredibly important, but it can be difficult, especially if you’ve never been pregnant before. You may want to explain away your symptoms with something you’re more familiar with—like stress, exhaustion, or PMS. But I gained nothing by telling myselfing I wasn’t pregnant.

Schedule an appointment to see a health care provider as soon as possible. In addition, monitor for the above symptoms, take a pregnancy test, and listen to your gut. The female body is strong, resilient, and capable of so many incredible feats, including growing another human being. And remember that if you are pregnant, or simply experiencing a strong case of PMS, your body is doing what it is designed to do!