Period or pregnancy symptoms: what’s the difference?
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Key takeaways
- Premenstrual syndrome (PMS) and early pregnancy share many symptoms: tender breasts, fatigue, bloating, nausea, and mood swings [1][2]. No single symptom can tell you for sure: a pregnancy test is the only reliable way to find out if you are pregnant [3].
- PMS symptoms generally disappear a few hours after your period starts [1]; in early pregnancy, your period does not arrive and the symptoms persist.
- A missed period is one of the first signs, but it can also have other causes, such as hormonal imbalance or significant stress [3].
- A urine test can be taken on the day your period is due, using your first morning urine; a positive test should be confirmed with a blood test [3].
- In case of severe pain, heavy bleeding, or feeling unwell, it is best to seek medical advice without delay [4][5].
"I have cramps and my breasts hurt. Is my period coming or am I pregnant?" Ouch, ouch, ouch… This is a question many women ask themselves when faced with misleading symptoms! If you are also torn between these two possibilities, don't panic: this article explains the signs, helps you see more clearly, and gives you the essential advice to clear up your doubts. Ready to understand the subtleties of your body? Read on!
What similar symptoms do PMS and pregnancy share?
Early signs of pregnancy or your period arriving? We agree, it can sometimes be difficult to tell the difference. Premenstrual syndrome (PMS) involves physical and psychological symptoms that begin a few days before your period [1]: it therefore occurs at the end of the luteal phase, the second half of the menstrual cycle, which extends from ovulation to the next period (from day 15 to day 28 of a 28-day cycle) [6]. To better understand this phase, check out our article "Planning a pregnancy: everything you need to know about the luteal phase". Here is an overview of the common symptoms and how to recognize them.
Nausea and changes in appetite
Nausea is one of the best-known signs of early pregnancy, sometimes accompanied by occasional vomiting [2]. It generally begins around the 5th week of pregnancy, roughly when your period is late, and peaks around 9 weeks [7]. But be aware: nausea can also accompany PMS [1]. In both cases, you may experience changes in appetite [1][2]:
- food cravings;
- binge eating;
- aversion to certain foods.
Digestive changes and weight fluctuations
In the family of early signs of pregnancy versus PMS, there are… bloating and water retention. Yuck! Yes, these discomforts can occur before your period as well as in early pregnancy [8][1]. For PMS, fluctuations in estrogen and progesterone levels contribute to this, and temporary weight gain is possible [1]. In early pregnancy, some women also experience abdominal swelling very early on [8].
Cramps and pain
Every expectant mother or woman about to have her period may experience cramps, a feeling of heaviness, or pressure in the lower abdomen [1]. In early pregnancy, mild pain, cramps, or pulling sensations may also occur: it is best to discuss them with a healthcare professional [3]. More intense or persistent pain should be evaluated (we will come back to this below) [5].
Mood swings and sleep problems
One last thing in common: mood swings and sleep problems. PMS can be accompanied by irritability, anxiety, insomnia, and fatigue [1]. In early pregnancy, hormones are all over the place, and it is not uncommon to go from laughter to tears without really knowing why [3]. Insomnia, irritability, feeling on edge… any woman can experience them!
Good to know
Early pregnancy symptoms vary from woman to woman, and from one pregnancy to another: some women experience many, while others experience none [3]. They can also be associated with hormonal imbalance, increased stress, premenstrual syndrome, or the onset of menopause [3]. For this last case, check out our article "Periods in perimenopause: duration, frequency, and flow."
What is the difference between period symptoms and pregnancy symptoms?
It is difficult to tell the difference between the start of a pregnancy and menstrual pain. However, there are differences! We have summarized them here to help you see more clearly.
Pain and cramps
Before your period, cramps are often accompanied by a feeling of heaviness or pressure in the lower abdomen, and ease with the arrival of your period [1]. In early pregnancy, mild sensations may occur; but intense, sudden, or worsening pain should always be evaluated [5].
Are you wondering about those famous situations where a pregnancy might go unnoticed? Check out our article "How to know if you are experiencing pregnancy denial?".
Nausea and changes in appetite
Even though eating habits can change before your period, nausea is not the most typical symptom of PMS [1]. In early pregnancy, it is more often associated with a late period: it is caused by hormones, especially the production of the hCG hormone, which begins about 10 days after fertilization [8]. It can be accompanied by changes in food preferences. Such as an aversion to coffee… Something we usually love. It feels strange, but that's how it is!
Breast changes
Breast tenderness occurs in both cases: in early pregnancy, breasts can become larger and more painful, like before your period [3][8]. The difference lies in the timing: before your period, these sensations ease with its arrival [1]; if they persist and your period does not arrive, a pregnancy test can give you the answer.
Mood and fatigue
During PMS, the most common symptoms are irritability, anxiety, low mood, and significant, or even severe, fatigue, and they stop shortly after your period starts [1]. In early pregnancy, unusual fatigue can set in [2], along with hormone-related mood swings [3]. The best indicator is therefore your menstrual cycle calendar: symptoms that last beyond the date your period is due should be checked with a test.
Vaginal discharge and cervical mucus
Odorless, milky, or clear and fluid vaginal discharge is normal in most women, and its appearance varies throughout the menstrual cycle [9]. It is mainly related to cervical secretions, known as cervical mucus. If you want to understand it better, our complete guide to the changes in cervical mucus throughout the menstrual cycle is here to help you. On their own, these discharges cannot tell you if you are pregnant: only a pregnancy test is reliable [3]. However, foul-smelling, gray, green, or yellow discharges, or those accompanied by itching or burning, should be discussed with a healthcare professional [9].
Bleeding
A missed period remains one of the first signs of early pregnancy, but it can also have other causes, such as hormonal imbalance or significant stress [3]. Furthermore, some bleeding can occur in early pregnancy and be mistaken for a period [3][5]. It is common: 20 to 30% of women experience vaginal bleeding during the first 20 weeks. In some cases, the pregnancy progresses normally, but medical advice is necessary to find out the cause [4]. If you think you are pregnant and notice bleeding, it is best to discuss it with a healthcare professional within 48 to 72 hours, and without delay in case of feeling unwell or severe pain [4]. To better understand this bleeding, check out our article on spotting.
Which symptoms are concerning?
In the vast majority of cases, everything is fine. Here are simply the signs that should be evaluated, whether you are pregnant or not:
- Severe or worsening pelvic pain. In early pregnancy, it may indicate an ectopic pregnancy or a miscarriage; sudden, severe, and constant pain in the lower abdomen requires immediate medical attention [5][4].
- Heavy bleeding, especially if accompanied by pain [4].
- Feeling unwell, dizziness, fainting, or a racing heart: seek medical attention immediately [4].
- Fever, chills, or burning when urinating: speak to your doctor or midwife promptly [8][4].
- Severe nausea and frequent vomiting, to the point of losing weight and becoming dehydrated: this is known as hyperemesis gravidarum and should be reported to a healthcare professional [7].
Later in pregnancy, other signs (severe headaches, visual disturbances, unusual swelling) warrant medical advice: our article on preeclampsia discusses this. If you check any of these boxes or have the slightest doubt, go see a healthcare professional, who will know how to take care of you and make the right diagnosis.
How can you tell if you are pregnant even though you had your period?
Can you be pregnant and have your period? The answer is no. Yet, many pregnant women have experienced light bleeding very early in pregnancy and mistaken it for their period [3]. If in doubt, it is best to speak to a doctor promptly [3]. Other signs can also put you on the right track: unusual fatigue, nausea, tender breasts [2]. To find out everything, check out our article "Can you be pregnant and have your period?".
When is the ideal time to take a pregnancy test?
Finding the right timing to take your pregnancy tests… It is quite an art! Because the ideal time depends on the type of test AND your menstrual cycle.
Good to know
A urine pregnancy test can be taken from the date your period is due, using your first morning urine, when it is most concentrated [3]. In any case, a positive test must be confirmed with a blood test [3].
| Test type | When to take it | Good to know |
|---|---|---|
| Urine test | From the expected date of your period [3]; if your cycles are irregular, 21 days after the intercourse that may have caused the pregnancy [10] | Sold in pharmacies, supermarkets, or online [3]; not covered by insurance [10] |
| Early detection urine test | Up to 6 days before the expected date of your period [3] | A test taken too early may not always detect a pregnancy [3] |
| Blood test | From 14 days after the intercourse that may have caused the pregnancy [3][10] | The most reliable test [3]; with a prescription (covered by insurance) or without a prescription (not covered by insurance) [3]; results generally within 24 hours [10] |
| Negative test but doubts persist | Retake the test a few days later [2] | If your period is still late despite a negative result, consult a healthcare professional [10] |
Keep in mind that a test taken too early may be negative even though a pregnancy is beginning [10], and that drinking a lot before taking it dilutes your urine, which is more reliable when concentrated [3]. If the result is negative but you still suspect a pregnancy, you should retake the test a few days later [2]; and if your period is still late despite a negative result, it is recommended to consult a healthcare professional [10]. Patience is key, so! To learn more, check out our article "When to take a pregnancy test: morning or evening?", and if your test is positive, our guide "Positive pregnancy test: what to do?".
Periods or pregnancy: differences at a glance
To summarize, here are the main differences between premenstrual syndrome and early pregnancy.
| Sign | Before your period (premenstrual syndrome) | Early pregnancy |
|---|---|---|
| Periods | They arrive, and symptoms generally disappear a few hours after they start [1] | Late or absent [2] |
| Breasts | Tender, swollen, and painful breasts [1] | Tender and swollen breasts, like before your period [8] |
| Nausea | Possible [1] | Common, sometimes with vomiting [2] |
| Frequent need to urinate | Not listed among the usual symptoms [1] | Common, without pain when urinating [2] |
| Fatigue | Possible, sometimes severe [1] | Unusual [2] |
Frequently Asked Questions
How can I tell the difference between premenstrual syndrome (PMS) and pregnancy symptoms?
Many symptoms are common. PMS symptoms generally disappear a few hours after your period starts [1]; in early pregnancy, your period will be absent or late [2]. Only a pregnancy test can confirm whether or not you are pregnant [3].
When in the cycle do PMS symptoms appear?
They start a few days before your period [1], at the end of the luteal phase, the second half of the menstrual cycle following ovulation [6].
Can you have pregnancy symptoms before your period is late?
Some symptoms, such as nausea, are caused by the hormone hCG, which is produced starting about 10 days after fertilization [8]. But because they resemble PMS symptoms [8], they are not conclusive: only a test can tell for sure.
Are vaginal discharge or cervical mucus a sign of pregnancy?
Not on their own: normal vaginal discharge varies throughout the menstrual cycle [9], and only a pregnancy test is reliable for determining whether or not you are pregnant [3].
When should I take a pregnancy test if my menstrual cycle is irregular?
It is recommended to take a urine test 21 days after the sexual intercourse that may have led to pregnancy, and a blood test starting 14 days after that intercourse [10].
Is a positive test enough to confirm a pregnancy?
In all cases, a positive test should be confirmed by a blood test [3].
Is it normal to have light bleeding in early pregnancy?
Some bleeding may occur in early pregnancy [3]. You should report it to a healthcare professional: see a doctor within 48 to 72 hours, and immediately if you experience malaise, dizziness, or severe pain [4].
Which symptoms require you to seek medical attention promptly?
Severe or worsening pain in the lower abdomen, heavy bleeding, malaise, or fainting [5][4].
Final word
Telling the difference between period symptoms and pregnancy symptoms can be difficult. But by paying close attention to your body's signs, you can clear up some of your doubts. So do not let your uncertainties linger: take a pregnancy test or consult a healthcare professional if needed. This is the surest way to confirm your situation!
