Sometimes, though, breakthrough bleeding may be a sign of a medical issue that requires evaluation and treatment.

In any case, here are some of the most common breakthrough bleeding causes that people experience.

They might give you an idea of whats up before you go in to see the doctor.

sanitary pad covered in red glitter

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You recently started a new birth control pill.

Spotting can also occur when you switch from a brand name to a generic, Dr. Moritz says.

Youre taking a very low-dose birth control pill.

You have an IUD.

AsSELF previously reported, this is because the gadget can irritate and inflame the uterus.

If your mid-cycle bleeding is accompanied by one-sided pain, you might be dealing withmittelschmerz.

Youve recently had sex.

If you experience persistentvaginal dryness, it can compound this issue.

If nothing is helping, your doctor might be able to offer more guidance.

Youre about to become pregnant.

Its just a little spot, not a lot, Dr. Moritz says.

You had vaginal intercourse while pregnant.

Its totally fine, he says.

It doesnt mean anything has happened to the babyhaving penetrative sex doesnt harm the fetus.

Youre pregnant and have a subchorionic hematoma.

Sometimes that blood flows out of the vagina, but sometimes it doesnt.

In any case, itspainlessand very common, Dr. Moritz says.

You have noncancerous growths on your ovaries, uterus, or cervix.

Bleeding doesnt necessarily occur with all of them.

Youve recently had an abortion.

In most cases, your provider will let you know how much bleeding to expect, theMayo Clinicexplains.

Youre having a miscarriage or ectopic pregnancy.

Cramping may also occur.

While ectopic pregnancies are rare, they can become life-threatening if a tube ruptures.

You have a sexually transmitted infection (STI).

This can cause complications like permanent damage to the fallopian tubes that leads tofertility issues.

You have a gynecological cancer.

Although cancer is unlikely, its a good idea to see your doctor to rule it out.

Any time after menopause, any spotting, even a drop, has to be investigated, he says.

This is especially important because breakthrough bleeding is a common symptom, but different conditions require different treatments.