Spotting is defined as light vaginal bleeding that happens outside of your regular periods.

Typically, spotting involves small amounts of blood. You may notice it on toilet paper after you’ve used the restroom, or in your underwear. It usually only requires a panty liner if you need protection, not a pad or tampon.

Bleeding or spotting any time other than when you have your period is considered abnormal vaginal bleeding, or intermenstrual bleeding.

There are many different causes for spotting between periods. Sometimes, it can be a sign of a serious problem, but it’s often nothing to worry about.

Read on to learn more about what could be causing your spotting.

There are several reasons you might experience spotting before your period. Many of these causes can be effectively treated or dealt with.

1. Birth control

Hormonal birth control pills, patches, injections, rings, and implants can all cause spotting between periods.

Spotting can happen spontaneously, or when you:

  • first start using a hormone-based birth control method
  • skip doses or don’t take your birth control pills correctly
  • change the type or dose of your birth control
  • use birth control for a long period of time

Sometimes, birth control is used to treat abnormal bleeding between periods. Talk to your doctor if your symptoms don’t improve or worsen.

2. Ovulation

About 3 percent of women experience spotting related to ovulation. Ovulation spotting is light bleeding that occurs around the time in your menstrual cycle when your ovary releases an egg. For many women, this can be anywhere between 11 days and 21 days after the first day of your last period.

Ovulation spotting may be light pink or red in color, and will last for about 1 to 2 days in the middle of your cycle. Other signs and symptoms of ovulation may include:

  • an increase in cervical mucus
  • cervical mucus that has the consistency and look of egg whites
  • a change in the position or firmness of the cervix
  • a decrease in basal body temperature before ovulation followed by a sharp increase after ovulation
  • increased sex drive
  • pain or a dull ache on one side of the abdomen
  • breast tenderness
  • bloating
  • an intensified sense of smell, taste, or vision

Paying close attention to these symptoms may help you narrow down your window to conceive.

3. Implantation bleeding

Implantation spotting may occur when a fertilized egg attaches to the inner lining of your uterus. But everyone doesn’t experience implantation bleeding when they become pregnant.

If it does occur, implantation spotting happens a few days before your next period should occur. Implantation bleeding is usually light pink to dark brown in color, much lighter in flow than a typical period, and doesn’t last as long as a typical period.

You may also experience the following with implantation:

  • headaches
  • nausea
  • mood swings
  • light cramping
  • breast tenderness
  • an ache in your lower back
  • fatigue

Implantation bleeding isn’t something to worry about and doesn’t pose any danger to an unborn baby. However, if you do experience heavy bleeding and know that you’re pregnant, you should seek medical attention.

4. Pregnancy

Spotting during pregnancy is not uncommon. About 15 to 25 percent of women will experience spotting during their first trimester. The bleeding is often light, and the color may be pink, red, or brown.

Usually, spotting isn’t a cause for concern, but you should let your doctor know if you have this symptom. If you experience heavy bleeding or pelvic pain, contact your doctor right away. This could be a sign of miscarriage or an ectopic (tubal) pregnancy.

5. Perimenopause

As you transition to menopause, you may have months where you don’t ovulate. This transitional time is called perimenopause.

During perimenopause, your periods become more irregular, and you may experience some spotting. You might also skip your periods altogether or have menstrual bleeding that’s lighter or heavier than usual.

6. Trauma

Trauma to the vagina or cervix can sometimes cause irregular spotting. This can be due to:

  • sexual assault
  • rough sex
  • an object, such as a tampon
  • a procedure, like a pelvic exam
  • If you’ve experienced sexual assault or were forced into any sexual activity, you should seek care from a trained healthcare provider. Organizations like the Rape, Abuse & Incest National Network (RAINN) offer support for survivors of rape or sexual assault. You can call RAINN’s 24/7 national sexual assault hotline at 800-656-4673 for anonymous, confidential help.

7. Uterine or cervical polyps

Polyps are small abnormal tissue growths that can occur in a number of places, including the cervix and uterus. Most polyps are benign, or noncancerous.

Cervical polyps typically don’t cause any symptoms, but may cause:

Your doctor can easily see cervical polyps during a routine pelvic exam. Generally, no treatment is needed unless they’re causing bothersome symptoms. If they do need to be removed, removal is generally easy and not painful.

Uterine polyps can only be seen on imaging tests like ultrasounds. They’re most often benign, but a small percentage can become cancerous. These polyps most commonly occur in people who have finished menopause.

Symptoms may include:

  • irregular menstrual bleeding
  • very heavy periods
  • vaginal bleeding after menopause
  • infertility

Some people may only experience light spotting, while others experience no symptoms at all.

8. Sexually transmitted infection

Sexually transmitted infections (STIs), such as chlamydia or gonorrhea, can cause spotting between periods or after sex. Other symptoms of STIs include:

Contact your doctor if you suspect an STI. Many STIs can be treated with minimal complications when caught early.

9. Pelvic inflammatory disease

Abnormal bleeding between periods is a common symptom of pelvic inflammatory disease (PID). You can develop PID if bacteria spreads from your vagina to your uterus, fallopian tubes, or ovaries.

Other symptoms include:

  • painful sex or urination
  • pain in the lower or upper abdomen
  • fever
  • increased or foul-smelling vaginal discharge

If you experience any signs of an infection or PID, see your doctor. Many infections can be successfully treated with the right therapies.

10. Fibroids

Uterine fibroids are growths on the uterus. In addition to spotting between periods, they can cause symptoms, such as:

  • heavy or longer periods
  • pelvic pain
  • low back pain
  • painful intercourse
  • urinary problems

Some women with uterine fibroids don’t experience any symptoms. Fibroids are also typically benign and may shrink on their own.

11. Endometriosis

Endometriosis happens when tissue that normally lines the inside of your uterus grows outside of the uterus. This condition can cause bleeding or spotting between periods, as well as other symptoms.

About 1 out of every 10 women in the United States is believed to have endometriosis, but many cases go undiagnosed.

Other signs and symptoms of endometriosis include:

  • pelvic pain and cramping
  • painful periods
  • heavy periods
  • painful intercourse
  • infertility
  • painful urination or bowel movements
  • diarrhea, constipation, bloating, or nausea
  • fatigue

12. Polycystic ovary syndrome (PCOS)

Irregular bleeding between periods is sometimes a sign of polycystic ovary syndrome (PCOS). This condition happens when a woman’s ovaries or adrenal glands produce too much “male” hormones.

Some women with PCOS don’t have their periods at all or have very few periods.

Other symptoms of PCOS include:

  • irregular menstrual periods
  • pelvic pain
  • weight gain
  • excessive hair growth
  • infertility
  • acne

13. Stress

Stress can cause all kinds of changes in your body, including fluctuations in your menstrual cycle. Some women may experience vaginal spotting due to high levels of physical or emotional stress.

14. Medications

Certain medicines, such as blood thinners, thyroid medications, and hormonal drugs, can cause vaginal bleeding between your periods.

Your doctor may be able to take you off these drugs or recommend alternatives.

15. Thyroid problems

Sometimes, an underactive thyroid can cause you to spot after your period ends. Other signs of an underactive thyroid (hypothyroidism) include:

  • fatigue
  • weight gain
  • constipation
  • dry skin
  • sensitivity to cold
  • hoarseness
  • thinning hair
  • muscle aches or weakness
  • joint pain or stiffness
  • high cholesterol levels
  • puffy face
  • depression
  • slowed heart rate

Treatment for an underactive thyroid usually involves taking an oral hormone pill.

16. Cancer

Certain cancers can cause abnormal bleeding, spotting, or other forms of vaginal discharge. These may include:

Most of the time, spotting isn’t a sign of cancer. But you should get checked out by your doctor, especially if you’ve already been through menopause.

17. Other causes

Certain medical conditions, such as diabetes, liver disease, kidney disease, and bleeding disorders, may cause spotting between your periods.

Talk to your doctor if you have these issues and experience spotting.

Spotting is different than the bleeding you experience when you have your period. Typically, spotting:

  • is lighter in flow than your period
  • is pink, reddish, or brown in color
  • doesn’t last longer than a day or two

On the other hand, bleeding due to your menstrual period:

  • is usually heavy enough to require a pad or tampon
  • lasts about 4-7 days
  • produces a total blood loss of about 30 to 80 milliliters (mL)
  • occurs every 21 to 35 days

If you’re of reproductive age, and you think pregnancy might be the reason you’re spotting, you can take an at-home test. Pregnancy tests measure the amount of human chorionic gonadotropin (hCG) in your urine. This hormone rises rapidly when you’re pregnant.

If your test comes back positive, make an appointment with your OB-GYN to confirm the results. You should also see your doctor if your period is over a week late and you have a negative pregnancy test.

Your doctor can run tests to determine if an underlying condition is responsible for your missed period.

You should see your doctor if you have unexplained spotting between your periods. Although it may be nothing to worry about or go away on its own, it could also be a sign of something more serious.

Try to record exactly when your spotting occurs and any other symptoms you have so you can share this information with your doctor.

You should see your doctor right away if the spotting is accompanied by:

  • fever
  • dizziness
  • easy bruising
  • abdominal pain
  • heavy bleeding
  • pelvic pain

It’s also especially important to make an appointment with your doctor if you’ve already been through menopause and experience spotting.

Your healthcare provider might perform a pelvic exam, order blood tests, or recommend imaging tests to find out what’s causing your symptoms.

Spotting before your period can be caused by a variety of factors. Some of these require prompt medical treatment, while others are harmless.

Any vaginal bleeding that happens when you don’t have your period is considered abnormal. You should see your doctor if you experience spotting.