Spotting, light vaginal bleeding lighter than a period, is common during pregnancy and happens to an estimated 15 to 25 percent of people in the first trimester alone. Many causes are harmless, such as implantation bleeding or cervical irritation, but spotting can occasionally signal something that needs prompt evaluation, including ectopic pregnancy or miscarriage. Because the same symptom can mean very different things, any spotting or bleeding in pregnancy should be reported to your provider, even if it stops on its own.

Common, Usually Harmless Causes

Implantation bleeding: Light spotting roughly 6 to 12 days after conception, often before a missed period, as the embryo implants in the uterine lining. It's typically pink or brown, very light, and brief.

Cervical irritation: During pregnancy the cervix has increased blood flow and can bleed slightly after sex, a pelvic exam, or a Pap smear. This is usually light and stops quickly.

Subchorionic hematoma: A collection of blood between the uterine wall and the placental membrane, found on ultrasound in some pregnancies. Many resolve on their own with no lasting effect, though larger ones are monitored more closely.

Cervical changes late in pregnancy: In the third trimester, especially close to the due date, spotting mixed with mucus ("bloody show") can signal that the cervix is beginning to change ahead of labor.

Causes That Need Evaluation

Ectopic pregnancy: When a fertilized egg implants outside the uterus, most often in a fallopian tube. This cannot continue safely and can become a medical emergency if the tube ruptures. It typically causes spotting along with one-sided pelvic pain, and sometimes shoulder-tip pain or dizziness.

Miscarriage: Spotting or bleeding, especially if it becomes heavier, is accompanied by cramping, or involves passing tissue, can be a sign of pregnancy loss. Miscarriage is confirmed through ultrasound and hormone level tracking, not by symptoms alone, so evaluation matters even when the outcome is uncertain.

Placental issues later in pregnancy: In the second and third trimesters, bleeding can be related to placenta previa (placenta covering the cervix) or placental abruption (placenta separating from the uterine wall early), both of which require prompt medical assessment.

Infection: Vaginal or cervical infections can sometimes cause spotting along with other symptoms like unusual discharge, odor, or itching, and are treatable once identified.

What Your Provider Will Likely Do

Evaluation for spotting typically includes a review of your symptoms and pregnancy history, a pelvic exam if needed, an ultrasound to check the location and viability of the pregnancy, and blood tests to track hCG (pregnancy hormone) levels, which can help clarify how a pregnancy is progressing when the exam and ultrasound alone don't give a full picture, particularly very early on.

What You Can Do While You Wait to Be Seen

• Track the amount, color, and pattern of bleeding, and note whether it's getting heavier or lighter.
• Use a pad, not a tampon, so you can monitor the amount.
• Avoid sex until you've talked to your provider if the cause of the spotting is unclear.
• Note any accompanying symptoms: cramping, pain, dizziness, fever, or passing tissue.

When to Seek Medical Care