11 Reasons Women Bleed During Pregnancy & What It Means for Baby

As thrilling as pregnancy is, it also comes with a lot of worrisome symptoms. Extreme morning sickness, painfully swollen breasts and feet, and sciatica are all par for the course. Though, one of the scariest things some moms-to-be experience is unexpected bleeding. It's a frightening moment. However, doctors say there are many reasons this can happen and, while it can be gravely serious, it doesn't always lead to losing a baby. Take a look at the 11 causes of bleeding during pregnancy and what it means for you and your baby.

First it's important to understand that bleeding during pregnancy is very common. In fact, "first trimester bleeding occurs in up to 40 percent of all pregnancies," says Dr. Arianna Sholes-Douglas, a Tuscon, Arizona–based ob-gyn and specialist in integrative medicine.

However, the appearance of the blood (color, thickness, amount) can signify how serious the problem may be. "Dark red or brown blood means old and is not that significant in pregnancy," says Dr. Annette Perez-Delboy, assistant clinical professor of obstetrics and gynecology at Columbia University. "It is usually seen as a spotting. It is common and is not threatening to the pregnancy. Pink mucus blood can be from the cervix due to dilation, abrasion, or other issues. Bright red blood means that it is fresh blood, and depending on how heavy the blood flow is, it means it may impact the pregnancy." 

pregnant woman
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1. Implantation Bleeding

Why it happens: Relatively common, it occurs when the fertilized egg attaches to the lining of the uterus. You may see bleeding 10 to 14 days after conception.

What you can do about it: There is no cause of alarm, assures Dr. Sholes-Douglas.

2.Premature Labor

Why it happens: Also called pre-term labor, it occurs when your body starts getting ready to deliver too early (usually after the 20th week or more than three weeks before your due date).

What you can do about it: "Recent treatment has been focusing on injections of a hormone called progesterone that helps relax the muscle of the uterus," explains Dr. Sami David, a New York–based reproductive endocrinologist. "There are also intravenous treatments with magnesium that also relaxes the uterine muscles and a medication called terbutaline."

However, just as important as treatment options is understanding WHY a woman is in premature labor. Is it from an infection? An abnormally shaped uterus? If you do deliver early, notes Dr. David, "there [have] been tremendous advances in survival rates of premature babies, so that women can deliver a baby at 26 weeks and expect a reasonable outcome."

3.Infection

Why it happens: An infection of the cervix or vagina caused by an STD.

What you can do about it: You can pass diseases like gonorrhea and herpes on to your baby during delivery. Make sure your doctor is aware of the condition so you can take all possible steps to avoid transmission.

4.Cervical Polyps

Why it happens: Usually diagnosed during a pelvic exam, they are growths most often caused by an increase in estrogen levels, inflammation, or clogged blood vessels in the cervix.

What you can do about it: Polyps can be removed during a simple outpatient procedure but "they are not dangerous to the baby," assures Dr. David. "They may cause bleeding in early pregnancy but rarely cause miscarriage after the first trimester."

5.Miscarriage

Why it happens: The most common cause of miscarriage in the first trimester is a fetus with chromosomal abnormalities. Other causes include genetic abnormalities, infection, medications, hormonal effects, structural abnormality of the uterus, and immune abnormalities.

What you can do about it: "There is no way to predict or prevent a miscarriage," adds Dr. Perez-Delboy. "We usually recommend bed rest while bleeding, no sexual intercourse, watch for the passage material from the vagina, or if bleeding persists, pain worsens, or you develop a fever, weakness, or dizziness."

6.Placenta Previa

Why it happens: It's one of the most common causes of third trimester bleeding. The problem begins when the placenta grows in the low part of the uterus and covers the cervical canal.

What you can do about it: "Once diagnosed, women are typically placed on bed rest and discouraged from having intercourse or participating in strenuous activities," explains Dr.  Sholes-Douglas. "If the previa does not resolve before the end of the pregnancy, C-section is mandatory. Oftentimes, however, if diagnosed early, the placenta will 'migrate' as the uterus enlarges. If a woman presents bleeding, she can expect her doctor to give her a medication to stop contractions, and often times she will receive steroids to help mature the baby's [lungs] in the case of early potential delivery."

7. Placental Abruption

Why it happens: In about 1 percent of pregnancies, the placenta detaches from the uterus wall and blood collects between the placenta and the uterus.

What you can do about it: Early detection is critical. "If it's not noticed immediately, it often results in the loss of the baby due to sudden loss of blood and oxygen," says Dr. David. "And there is increased risk of the mother hemorrhaging."

8.Uterine Rupture

Why it happens: If there is a weakness in the muscle caused by a previous surgery (like a C-section or fibroid removal), that area can break open during pregnancy and the baby will be forced into the mom's abdomen.

What you can do about it: It's a life-threatening condition, and doctors recommend an emergency C-section to save mother and baby.

9.Ectopic Pregnancy

Why it happens: The embryo implants outside the uterus, typically in the fallopian tube. It can be very dangerous to the mother if the embryo keeps growing and causes the tubes to burst.

What you can do about it: For Mom's safety, this kind of pregnancy is not able to go to term. It can be treated in two ways: "An injection of the drug methotrexate is sometimes used to stop cell growth and dissolve existing cells," says Dr. Perez-Delboy. "It can also be treated with surgery, mini-laparotomy or a laparoscopy."

10.Molar Pregnancy

Why it happens: A very, very rare condition, it's caused when a fertilized egg develops into a growth called a mole instead of a baby. You may still have some regular pregnancy symptoms even though this is not a viable pregnancy. 

What you can do about it: The mole must be removed with suction and curettage (also called a D&C), explains Dr. Perez-Delboy.

11.Vasa Previa

Why it happens: A rare condition caused when a developing baby's blood vessels in the umbilical cord or placenta cross the birth canal. It's dangerous because those blood vessels can tear open causing the baby to bleed and lose oxygen.

What you can do about it: "If the mother goes into labor, these blood vessels may break, leading to a hemorrhage that will threaten mother and baby," warns Dr. David. "Like placenta previa, the recommended way to deliver is by cesarean section."