Why Am I Spotting Between Periods?

You’re in the bathroom at work, and there’s a spot of pink on the paper. Your period isn’t due for two weeks. You check the calendar, then your phone, then yourself, as if one of them knew.

The common causes

Hormonal birth control. Cleveland Clinic³ says it’s the most common cause of what it calls breakthrough bleeding. The risk goes up when you miss a pill, switch to a new form of birth control, or use a low-dose one. It can last a few hours or a few days and typically stays light. The body takes a couple of months to adjust to new hormones, and Cleveland Clinic says breakthrough bleeding can take up to three months to improve. MedlinePlus¹ lists IUD use, which may cause occasional spotting.

Perimenopause. Cleveland Clinic³ says ovulation shifts are common in the years before menopause, and that spotting is frequent in perimenopause and menopause. Our article on perimenopause covers the other signs, and late or irregular periods may be part of the same picture.

Polyps and fibroids. The NHS² lists small growths in and around the womb such as polyps or fibroids, and Cleveland Clinic³ and MedlinePlus¹ agree. They’re noncancerous.

Infections. The NHS² lists sexually transmitted infections. MedlinePlus¹ lists inflammation or infection of the cervix or uterus. Cleveland Clinic³ points out that some people with an STI have no signs or symptoms. For the vaginal infections, see bacterial vaginosis and yeast infections.

PCOS/PMOS. Cleveland Clinic³ says this condition disrupts ovulation and can cause irregular bleeding along with other symptoms.

Other medical causes. Cleveland Clinic⁴ lists blood clotting disorders, thyroid, liver and kidney disease, and pregnancy complications. MedlinePlus¹ lists blood thinners and ectopic pregnancy or miscarriage.

After sex. The NHS² lists changes on the surface of the cervix, cervical polyps, vaginal dryness and STIs. If dryness is part of it, see vaginal dryness.

What a clinician does

The NHS² says your doctor may do a pregnancy test, blood tests, STI screening and an exam of the vagina and cervix, with imaging such as an ultrasound or a colposcopy if needed. Cleveland Clinic³ lists a pelvic exam, cultures, blood tests or imaging.

The play

Try this: a spotting log

Write the date each time you spot, how much it was (a few drops, a panty liner, a pad), the color, and how long it lasted.

Add where you are in your cycle, any missed pills or a new birth control, sex in the last day, and any pain.

Cleveland Clinic³ says tracking when bleeding occurs and how often helps, and a few weeks of notes turns a worry into a pattern.

When to get checked

Don’t wait if

1. Urgent

   Get urgent medical care right away if you’ve recently missed a period and have unusual vaginal bleeding and pain anywhere in your belly. The NHS² says that combination may be an ectopic pregnancy.

MedlinePlus¹ says to seek care for any unexplained bleeding between periods, any bleeding after menopause, or abnormal bleeding with other symptoms such as pelvic pain, fatigue or dizziness. Cleveland Clinic⁴ adds bleeding after intercourse, spotting that persists, gets worse or recurs, easy bruising, fever and abnormal discharge. On birth control, Cleveland Clinic says to call if bleeding lasts beyond three months, you’re soaking through several pads or tampons a day, you have pain or fever, or you’re pregnant. The NHS² says to see a GP or sexual health clinic for bleeding between periods or after sex.

Book an appointment if any of these fit:

• You’re bleeding between periods and don’t know why
• You bleed after sex
• You’re past menopause and bleeding at all
• It has lasted more than three months on birth control
• You’re soaking through pads or tampons, or you feel dizzy or tired
• You have pelvic pain, fever or unusual discharge

The pink on the paper is information. Write it down, call, and let someone with the full picture read it.