What causes spotting between periods?

Medically reviewed by Rosanna Sutherby on December 3, 2019. Written by Jordana White. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

Any time you have abnormal vaginal bleeding, it can be frightening. You want to know why it’s happening and what it can mean for your overall health. There are many reasons why you might be spotting outside of your menstrual cycle. Some are harmless, but some could be a sign of a serious health problem. That’s why it’s important to determine the cause of spotting, or intermenstrual bleeding [1].

Often, spotting between your menstrual cycle happens as a result of implantation bleeding [2]. If you're wondering when implantation bleeding occurs, how long implantation bleeding lasts, and what implantation spotting looks like, read more below.

Common causes

Spotting between periods can happen for a variety of reasons. Some spotting causes will be relatively easy to treat, while others may require more serious intervention.

Sexually transmitted infections (STIs)

Sexually transmitted infections (STIs) like chlamydia can cause bleeding between periods [3]. If left untreated, chlamydia can lead to serious complications. A convenient way to test is with the Everlywell Chlamydia & Gonorrhea Test.

If you’re having unprotected sex and believe that you may have been exposed to an STI or are experiencing irregular menstrual cycle issues and spotting, the Everlywell at-home STD Test for women is an easy way to check for six common STIs.

Birth control

If you use hormonal birth control, like birth control pills or an IUD (intrauterine device), spotting is common in the first three months [4]. Known as breakthrough bleeding, this spotting occurs as your body’s new hormone balance changes your uterine lining. You should mention the bleeding to your healthcare provider, but it will likely disappear once your body adjusts to the new birth control.

Implantation bleeding

In the early days of pregnancy, you may experience implantation bleeding (spotting associated with an embryo implanting in your uterus.) This kind of spotting doesn’t look like a period.  It may be light—you’ll notice a bit of blood as you wipe—but your implantation bleeding may also have a light, consistent flow. You may even need to wear a liner or pad. Sometimes, implantation bleeding may mix with cervical mucus. It may be red (light or dark), orange, pink, or even brown. Implantation bleeding typically doesn’t last long—it should stop after a few days.

Not every pregnant woman will experience implantation bleeding, but if you do, it will usually occur 10 to 14 days after conception (about the time you’d notice a missed period.) Sometimes, implantation bleeding shows up later in your pregnancy. It is considered normal up to the eighth week of pregnancy. Still, if you may be pregnant and you notice spotting, record the frequency and approximate volume. See your healthcare provider to discuss as well.

Pregnancy complications

Sometimes, abnormal vaginal bleeding can be a sign of problems with your pregnancy [5]. If you have an ectopic pregnancy—where the embryo implants in your fallopian tubes instead of your uterus—you will likely experience vaginal bleeding. Vaginal bleeding when you’re pregnant can also be a sign of miscarriage. See your healthcare provider any time you notice bleeding during pregnancy.

Related health conditions

Though less common, other health conditions may cause you to bleed between your periods.

• Fibroids: these are muscular tumors that grow in or on your uterus. Though not cancerous, they can cause you to experience long, heavy periods, and bleeding outside your menstrual cycle [6].
• Polycystic ovary syndrome (PCOS): with this condition, your ovaries don’t release eggs on time, causing them to become enlarged. If you have PCOS, you may lose your period, have irregular periods, or notice bleeding between periods [7].
• Cancer: cancers of your uterus, vagina, ovaries and cervix can all present with spotting between periods [8].

Seeking medical care

Any time you have abnormal vaginal bleeding, you should talk to your healthcare provider, especially if you’re pregnant or have already been through menopause. If you’re spotting and experience other symptoms, you may need emergency medical care. These symptoms may include:

• Dizziness
• Pain, especially in your lower abdomen
• Fever
• Extreme fatigue

Common questions

How do I know if I’m spotting or it’s my period?

Your period isn’t always regular, so it can sometimes be hard to differentiate between an early period and bleeding outside of your period. With spotting, unlike your period, you usually produce less blood than your period. And the color of your blood is usually lighter with spotting than with your period.

How do I know if I am experiencing abnormal vaginal bleeding?

While many women, especially adolescents, have irregular periods, it's still important to be aware of what your normal menstrual cycle looks like and what symptoms you have regularly. If your periods suddenly become less frequent, heavier, or you experience spotting, it's important to speak with a healthcare provider.

Tracking your menstrual cycle each month helps you stay aware of any potential changes in your health. Irregular periods may be caused by a hormonal imbalance. If you notice that you have experienced mood changes, feel depressed, or experience headaches, you might want to take a hormone imbalance test.