Around one in four pregnant women have spotting or bleeding during pregnancy. It may occur at different times, and in some cases, could be a cause for alarm too (1). If you experience spotting during pregnancy, see a doctor for appropriate diagnosis and care.
This MomJunction post tells you about the possible causes of pregnancy spotting or bleeding, and when to see a doctor.
Spotting Versus Bleeding During Pregnancy
Spotting refers to the light flow of a few drops of blood that would not soak a sanitary pad. It might happen during the first trimester and is usually not harmful (2).
Bleeding refers to the heavy flow of blood that soaks a panty liner or a sanitary pad (2). Bleeding from the vagina might happen anytime from the time you conceive to the time you reach the term.
Whether you are spotting or bleeding, you should see a doctor.
How Much Bleeding Is Considered Normal During Pregnancy?
Light bleeding, especially spotting, occurs in early pregnancy when the fertilized egg implants into the uterus. Bleeding could be considered normal until it does not soak a sanitary pad or a panty liner (2).
Causes Of Spotting During Pregnancy
Any of the following conditions may cause spotting that is light and usually harmless.
During the first trimester
- Implantation bleeding: Implantation bleeding occurs around the time you expect your period and is often mistaken for a period (3) (4). Spotting as a result of implantation bleeding lasts for a few hours to a few days, and is usually brown or pink in color.
- Cervical changes are observed during early pregnancy and sometimes may cause bleeding, for example after sex.
During the third trimester
- You may lose the mucus plug, referred to as bloody show, from the cervix. It is an indication your cervix is getting ready for labor. It is likely to happen a few days before the contractions commence or in labor itself (5).
- Cervical changes in the third trimester present blood after sex.
Anytime during pregnancy
- The cervix becomes tender and swollen in pregnancy. Any kind of strain to the cervix during an internal examination or intercourse could cause spotting (6). This may not indicate a problem unless it is severe and painful.
- Any infection in the vagina or cervix could lead to irritation or inflammation and cause spotting. A blood culture test is recommended to determine if an infection is bacterial, viral, or sexually transmitted (7). A specimen of vaginal fluids is necessary to exclude an infection of streptococcus B or other bacteria which may influence the growth of the fetus.
- In subchorionic hemorrhage, blood gets accumulated between the uterine lining and the chorion (outer fetal membrane) and could result in light to heavy spotting (8). It usually resolves by itself and is not likely to cause any problem in pregnancy.
Causes Of Bleeding During Pregnancy
Heavy vaginal bleeding anytime during pregnancy usually indicates a problem. It could be a benign sign only in rare cases.
During the first trimester
- Ectopic pregnancy: It occurs when the fertilized embryo implants outside the uterus, usually in the fallopian tube. As it is a nonviable pregnancy, it might get ruptured, causing bleeding, abdominal pain, lightheadedness, rectal pressure, and shock (9).
- Molar pregnancy: Also referred to as gestational trophoblastic disease, molar pregnancy occurs when an abnormal placental tissue forms instead of an embryo. You might experience bleeding along with nausea, vomiting, and cramping (10).
- Miscarriage: It is a pregnancy loss in the first 12 weeks of pregnancy that might happen due to genetic or chromosomal defects, and also hormonal, blood clotting problems and other reasons. Heavy bleeding accompanies severe cramping and pain in the lower abdomen and back (11).
During the second and third trimesters
- Placenta previa: This is a placental condition, wherein the placenta covers the cervix completely or partially. It is usually spotted when it begins to bleed. Later in pregnancy, as the cervical opening thins and dilates, the placenta stretches and ruptures, resulting in heavy bleeding (12). and posing risk to mother and baby.
- Placental abruption: It is the early detachment of the placenta from the uterine wall, which leads to the pooling of blood in between the placenta and uterus. It is accompanied by severe cramping, abdominal pain, and back pain (13).
- Preterm labor: If you start experiencing regular contractions, bleeding, or spotting along with other labor signs before the 37th week, it could be preterm labor (14). If you suspect labor, you should immediately contact your doctor.
- Fetal vessel rupture (vasa previa): In this condition, the fetal blood vessels of the umbilical cord get attached to the membranes of the cervix instead of the placenta. They pass over the opening of the birth canal, which, when ruptured, may get torn and bleed (15). As a result, the neonate may lose a life-threatening amount of blood.
- Uterine rupture: Sometimes, there could be a spontaneous tearing of the uterus that may expel the fetus into the abdomen. It might happen at the scar line of the previous C-section and is an emergency condition. You may experience abdominal pain and tenderness, along with vaginal bleeding (16).
What Should You Do If You Have Abnormal Bleeding During Pregnancy?
As bleeding during any trimester could signal a problem, it is essential to see your doctor and discuss the symptoms.
- Wear a sanitary pad to measure the bleeding and observe the type of blood—check if it is brown, red, or pink; smooth; or contains clots.
- If you notice any tissue passing from the vagina, get it to the doctor for examination.
- Do not indulge in intercourse or use a tampon while bleeding.
The following signs and symptoms could be signs of a miscarriage or any other condition (17).
- Severe and heavy bleeding whether or not associated with pain
- Severe cramps in the lower abdomen
- Fainting or dizziness
- A fever of more than 100.4°F
- A localized pain in the abdomen, back, or pelvis
- Vaginal discharge containing tissue
Diagnosis Of Spotting And Bleeding While Pregnant
Medical diagnosis begins with a thorough examination of the patient’s history and physical state. Depending on the severity of the bleeding, the seriousness of symptoms, and gestational age, the following tests are performed to find the cause (17).
- Ultrasound examination: It is performed to know if the fetus is in the uterus and fetal heartbeat is normal. It also helps in determining the placental location and evidence of fetal bleeding and genital tract problems.
- hCG hormone level tests: They help determine if the pregnancy is viable. However, these tests are helpful only in the initial six weeks. Once the ultrasound confirms the fetus in the uterus, these tests are not required.
- Speculum examination: The cervix is visually examined to check if the bleeding is due to pelvic infection, cervical laceration, cervical dilation, or mucus plug.
Treatment of spotting and bleeding during pregnancy depends on its cause.
Can Bleeding During Pregnancy Be Prevented?
There are no specific measures to prevent spotting or bleeding. If you have had complications in the previous pregnancies, let your doctor know about it.
The following tips could help in reducing the risk of pregnancy bleeding (18):
- Take rest and de-stress
- Avoid sex if you notice any spotting
- Quit illegal drugs, nicotine, and alcohol
- If you have high blood pressure or diabetes, get regular follow-ups and medications
- Do not ignore any abnormal changes in your pregnancy
Frequently Asked Questions
1. Does bleeding during pregnancy affect my baby?
You baby may be affected in severe conditions such as placental abruption, where the baby may not receive nutrients and oxygen as the placenta gets separated (6).
2. Is bleeding a sign of pregnancy?
Light bleeding or spotting is associated with implantation. It usually happens between six and 12 days of conception, that is, when your period is due (18).
Light spotting may not pose a risk to your pregnancy. However, bleeding could indicate some anomalies in your pregnancy. See your healthcare provider if you are spotting or bleeding.
2. Vaginal bleeding in early pregnancy; U.S. Department of Health and Human Services
3. Vaginal bleeding in pregnancy; NHS
4. Why spotting between periods happens and when to be concerned; The Ohio State University Wexner Medical Center
5. The Signs and Stages of Labor; Beth Israel Lahey Health – Winchester Hospital
6. Bleeding During Pregnancy; The American College of Obstetricians and Gynecologists
7. Vaginitis; University of Rochester Medical Center
8. Kimberly D. Walker, Kathy Dexter, and Bonnie A. Dadig; Vaginal bleeding in the early stages of pregnancy; The Clinical Advisor; Augusta University (2013).
9. Ectopic Pregnancy; University of Rochester Medical Center
10. What is a molar pregnancy; Obstetrics and Gynecology | Northwell Health
11. Miscarriage; National Institutes of Health
12. Placenta Previa; University of Rochester Medical Center
13. Pamela Schmidt, Christy L. Skelly, and Deborah A. Raines; Placental Abruption (Abruptio Placentae); StatPearls Publishing (2020)
14. Premature Birth; CDC
15. Sujata Datta et al.; Vasa Previa: An Avoidable Obstetric Tragedy; The Journal of Obstetrics and Gynecology of India (2016).
16. Kevin S. Toppenberg and William A. Block; Uterine Rupture: What Family Physicians Need to Know; American Academy of Family Physicians (2002).
17. Is spotting during pregnancy normal; Sanford Health
18. Alok Sharma and Pratap Kumar; Understanding implantation window, a crucial phenomenon; Journal of Human Reproductive Sciences (2012).