Bleeding Between Periods: What You Need to Know

Bleeding between periods can be disconcerting, especially if you do not know the cause. Unusual bleeding between periods can be called spotting, intermenstrual bleeding, and metrorrhagia. It can occur for various reasons—not all concerning. So, don’t jump to anxious conclusions if this happens to you.

However, it’s worth understanding what might explain bleeding outside your menstrual period. This will help you determine whether to seek help.

First, let’s take a moment to distinguish unusual vaginal bleeding from normal vaginal bleeding (i.e. periods or menses).

Understanding Bleeding in Between Periods

Monthly periods typically include lighter and heavier days. Some describe the lighter days at the start or end of their period as spotting. However, although it can be difficult to tell the difference, menstruation and non-period bleeding are different.

In general, spotting is any light bleeding outside of menstrual bleeding (i.e., the shedding of the uterus lining). While spotting has a lot of different causes (see below), it is generally lighter and does not require more than a panty liner or leakproof underwear.

You should seek immediate medical care if you experience prolonged bleeding that is not your period. Here’s an overview to help you tell the difference:

Common Causes of Abnormal Uterine Bleeding Between Periods

This next section may be overwhelming. The truth is there are many possible explanations for spotting between periods. You can rule out some of these independently (e.g. if you’re not on medication or know you're not pregnant). But others will require a doctor’s visit. 

This list is not exhaustive, but these are the most common causes of bleeding between periods.

Birth Control Causes

• Birth control pill: According to the American College of Obstetricians and Gynecologists, irregular bleeding often occurs in the first 6 months of taking a new medication (hormonal contraceptives). Doctors sometimes refer to this as breakthrough bleeding.
• Morning-after pill: According to the Mayo Clinic, the morning-after pill (a.k.a. emergency birth control) can cause bleeding between periods or heavy bleeding during periods.
• Intrauterine device (IUD): Some women who've opted for an IUD for birth control may also experience non-period bleeding. Whether a hormonal or non-hormonal IUD, "during the first few months, you may experience irregular bleeding and/or cramping," according to the Cleveland Clinic.

External Causes of Abnormal Vaginal Bleeding Between Periods

• Trauma or medical examination: If you’ve experienced rough sex or a medical exam like a Pap test, you may experience vaginal bleeding.
• Medications: Certain medications (not just birth control pills and other hormonal contraceptives or hormonal birth control methods) may cause abnormal vaginal bleeding, such as breakthrough bleeding. Your pharmacist should advise you of any side effects of the medication.
• Stress: Stress can trigger many reactions due to hormonal fluctuations, and sometimes, bleeding occurs.

Common Infections

The following infections can cause spotting between regular periods (including considerations for sexually active women). It’s worth noting that most diseases are treatable. However, conditions can become more severe if ignored, so you should seek medical attention.

• Sexually transmitted infections (STIs), including chlamydia, gonorrhea, and genital warts
• Pelvic inflammatory disease (PID), an infection of the upper part of the female reproductive system

Pregnancy-Related Causes

• Ovulation: When the ovaries release an oocyte (immature egg), a tiny follicle ruptures to allow it to be released. This can be a cause of bleeding for a day or so.
• Implantation bleeding: After a sperm fertilizes an egg, the egg implants in the womb. Sometimes, once the fertilized egg implants, it causes light bleeding or implantation bleeding.
• Ectopic pregnancy: When an ectopic pregnancy occurs, signs and symptoms include abdominal and pelvic pain and vaginal bleeding.
• Pregnancy: According to the American Pregnancy Association, 20% of women experience spotting during the first 12 weeks of pregnancy.
• Miscarriage: Heavy spotting is one of the signs of miscarriage.
• Breastfeeding: Spotting may occur before full periods return, depending on the breastfeeding frequency and your hormones.

Other Causes

• Uterine fibroids or polyps: These benign tumors can cause irregular or heavy periods and vaginal bleeding between periods.
• Endometriosis: According to the Mayo Clinic, women with endometriosis may experience heavier bleeding during their periods or bleeding between periods (intermenstrual bleeding).
• Polycystic ovary syndrome (PCOS): Polycystic ovary syndrome can cause cysts in the ovaries and make it difficult to get pregnant. It can also cause irregular vaginal bleeding.
• Blood clotting disorders, like von Willebrand disease.
• Other health conditions, like hypothyroidism, liver disease, or chronic kidney disease.
• Cancer or precancer: Cervical cancer, uterine cancer, or (very rarely) cancer of the fallopian tubes can cause spotting.

Perimenopause & Menopause

• Perimenopause: The time before menopause is known as perimenopause. During perimenopause, hormones fluctuate considerably. Hormone imbalances can affect ovulation and your entire menstrual cycle. Some women notice irregular or skipped periods and abnormal bleeding between periods during perimenopause. 
• Vaginal dryness, mainly due to lack of estrogen after menopause, can cause spotting.
• Cancer: According to the Dana-Farber Cancer Institute, postmenopausal women who experience bleeding should speak with their healthcare providers. Sometimes, spotting can be an early sign of cancer and should always be investigated further.

When to Seek Medical Help

If you experience heavy spotting outside your period (requiring a tampon or pad), we advise you to seek medical advice.

If you’re experiencing occasional spotting but no other symptoms or pain, we recommend monitoring your cycle by keeping a period diary. You may find it occurs on a regular cycle (e.g., during ovulation). 

If any of the following symptoms accompanies bleeding, it warrants a trip to the doctor for a physical exam to determine the underlying cause and treatment options, if necessary:

• Heavy periods with a lot of clotting
• Irregular periods
• Abdominal pain or cramping (painful periods)
• Pain or a burning sensation when peeing
• Unusual vaginal discharge and/or redness and itchiness

Even if you don’t have any of the above symptoms, don’t ever ignore abnormal bleeding in the following situations:

• If you think you’re pregnant: You should always see a doctor as soon as you think you may be pregnant to be administered a pregnancy test.
• When it happens inconsistently: If spotting happens frequently and randomly, you should look into it.
• It begins after unprotected sex: Unprotected sex can put you at risk for STIs and other infections. So, if you notice spotting after unprotected sex, visiting a doctor is wise.
• You are on medication that may cause spotting: If spotting can be a side effect of any medication you are on, you should seek out professional help.
• Postmenopausal bleeding: It is never considered normal for anybody postmenopause to experience spotting or vaginal bleeding.

If you're at all anxious or losing sleep over any experience related to your health, it's always worth checking with a medical professional. Even if they reassure you that there's nothing to worry about and it's not life-threatening, you can move on from fear and anxiety. 

And if there is a cause for concern, you'll be glad you investigated it early so you can move through the steps of diagnosis and treatment with your doctor!

Frequently Asked Questions

When Should I Go to the Doctor for Bleeding Between Periods?

You should consult a doctor for bleeding between periods if:

• It's frequent or heavy
• It lasts more than a week or is recurring
• It is accompanied by pain or discomfort
• It is new or unusual
• It is associated with other concerning symptoms
• You are sexually active, and it's unrelated to your menstrual cycle
• You are postmenopausal and experience any bleeding

Why Am I Spotting 2 Weeks Before My Period?

Spotting 2 weeks before your period may be due to various factors, including ovulation, hormonal imbalances, stress, hormonal birth control, infections, medication, or, if you're sexually active, it could be related to implantation bleeding. If it's persistent or concerning, you should consult a healthcare provider.

Can Stress Cause Bleeding Between Periods?

Yes, stress can cause or contribute to bleeding between periods. High stress levels can disrupt your menstrual cycle and lead to irregular bleeding. Stress affects the body in various ways, including hormonal changes, which can impact the regularity of your menstrual cycle. "If you’re living with stress, try exercising regularly, meditating, and keeping a positive attitude to manage stress," according to Advanced Women's Healthcare.

Written by Jane Flanagan — Updated on Oct. 22, 2023.

We hope you found this post informative — but remember: we’re not doctors and this post is not medical advice! While all posts are fact-checked and well researched, we always recommend you chat with your doctor about any questions or concerns you might have regarding a medical condition. We’re here to support and educate, but never with the aim of disregarding professional medical advice you’ve been given. Phew, now that that’s out of the way, you can go on living unapologetically free.