Spotting during pregnancy causes many women to panic that they might be having a miscarriage or chemical pregnancy, but most of the time, it’s no cause for alarm. There are a variety of reasons why you might experience spotting, brown discharge—or even heavy bleeding with clots—during pregnancy. But the statistics around spotting and pregnancy outcomes are reassuring.
Vaginal bleeding in early pregnancy is relatively common, affecting 10 – 15 percent of women1. While it’s considered a risk factor for miscarriage, preterm delivery, and low birth weight2, many sources suggest that the increased risk of these issues is slight, and most women who experience spotting go on to have healthy, full-term pregnancies.
What Causes Spotting During Early Pregnancy?
Sometimes spotting happens without any identifiable cause. It’s just one of those unexplainable pregnancy things. Other times, there is an explanation for the spotting or bleeding, and it’s usually nothing bad. Here are some of the common causes of spotting or bleeding during pregnancy:
Irritation to the Cervix
The cervix may be more sensitive and prone to bleeding during pregnancy. Anything that irritates the cervix—like sexual intercourse, transvaginal ultrasound, or progesterone suppositories—might lead to bleeding.
No Known Cause
It’s frustrating, but sometimes spotting or bleeding can happen during pregnancy without any identifiable cause.
Implantation Bleeding? It’s a Myth.
Many women believe that when spotting occurs in very early pregnancy, it is implantation bleeding. However, there is no medical evidence that implantation bleeding exists. Spotting in the luteal phase is fairly common in both pregnancy and non-pregnancy cycles. When spotting occurs in early pregnancy, it usually does not occur on the day of implantation (one study found that most bleeding began at least five days after implantation)3.
Subchorionic hematoma is the accumulation of blood within the folds of the outer fetal membrane, or between the uterus and the placenta. Sometimes there is no bleeding, and sometimes there is light to heavy spotting. Most of the time, subchorionic hematoma resolves on its own, and does not impact the health of the pregnancy.
Infections (such as bacterial vaginosis) can irritate the vagina or cervix and cause light bleeding or spotting. Seek treatment for the infection and the spotting should resolve.
Seeing blood during pregnancy is scary, but it doesn’t usually mean that you’re having a miscarriage or chemical pregnancy. One study found that of all pregnancies with bleeding, 14 percent miscarried, compared to nine percent miscarrying in pregnancies without bleeding. And the majority of pregnancies that miscarried had no bleeding in early pregnancy.
How do you know if spotting is benign or a sign of something bad? Unfortunately, there’s no foolproof way to tell. Sometimes vaginal bleeding can be heavy with clots, and everything is fine. Other times, light spotting can signal a miscarriage. There isn’t a hard and fast way to map spotting type to pregnancy loss risk. However, one study found that bleeding that stops and then resumes later may be more ominous. There were two women who experienced this bleeding pattern in the study, and they were the only two women with bleeding who went on to miscarry4.
An ectopic pregnancy occurs when the fertilized egg implants somewhere other than the uterus—most commonly, in the fallopian tubes. Often, ectopic pregnancies come with vaginal bleeding that can be anywhere from light spotting to period-like flow. Other symptoms of ectopic pregnancy include one-sided pain and weakness or dizziness. An ectopic pregnancy is a serious medical condition that requires treatment. If you suspect you have one, you should contact your medical provider immediately.
- Ananth, C.V. and Savitz, D.A. (1994) Vaginal bleeding and adverse reproductive outcomes: a meta‐analysis. Paediatr. Perinat. Epidemiol., 8, 62–78. <http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3016.1994.tb00436.x/full> ↩
- Batzofin, J.H., Fielding, W.L. and Friedman, E.A. (1984) Effect of vaginal bleeding in early pregnancy on outcome. Obstet. Gynecol. <http://journals.lww.com/greenjournal/abstract/1984/04000/effect_of_vaginal_bleeding_in_early_pregnancy_on.15.aspx>. ↩
- “Vaginal bleeding in very early pregnancy,” https://doi.org/10.1093/humrep/deg379 ↩ Human Reproduction, Volume 18, Issue 9, 1 September 2003, Pages 1944–1947,
- ibid ↩