Pregnancy Complications

Pregnancy complications overview

  • Many women experience pregnancy complications that can range from mild to life threatening.
  • Pregnancy complications include preterm delivery, high blood pressure and ectopic pregnancy.
  • Some complications can be treated with a simple change in diet, while others require more extensive treatment, monitoring or fertility treatment to bypass a complication.

What are common pregnancy complications?

Vaginal bleeding

About 15-20 percent of pregnant women experience vaginal bleeding during the first trimester. Many women associate vaginal bleeding with experiencing a miscarriage, but only 50 percent of women who experience vaginal bleeding will have a miscarriage.

Bleeding in the second or third trimester may indicate a larger problem such as:

  • Placental abruption, in which the placenta separates from the uterine wall, leading to life-threatening complications for both mother and baby
  • Placenta previa, when the placenta lies too low in the uterus, requiring immediate medical attention
  • Preterm labor, labor before the 37th week of pregnancy.


Anemia is a deficiency of iron, which is a mineral needed to transport oxygen from the lungs to the rest of the body. Anemia can cause a pregnant woman to feel tired and weak. Untreated, anemia can put pregnant women at a higher risk for preterm labor.

Iron and folic acid supplements can help control anemia. A woman’s healthcare provider will periodically take blood tests to check iron levels throughout pregnancy.

Hypertension (high blood pressure)

The rise and fall of blood pressure throughout the day is normal. However, if blood pressure stays too high for too long, complications can arise. Pregnancy induced hypertension may lead to other life-threatening conditions for both mother and baby such as:

  • Preeclampsia, a large spike in blood pressure after the 20th week of pregnancy, requiring delivery of the baby
  • Placental abruption
  • Gestational diabetes, which occurs when the body cannot appropriately digest sugars and carbohydrates during pregnancy.

Ectopic pregnancy

An ectopic pregnancy, commonly referred to as a “tubal pregnancy,” occurs anytime the embryo implants outside the uterus, most commonly in the fallopian tube. An ectopic pregnancy cannot survive, and must be treated with medication to pass the ectopic tissue or surgery to remove the ectopic tissue and possibly the affected fallopian tube.

Women with the following factors are more susceptible to an ectopic pregnancy:

Woman who have experienced an ectopic pregnancy can undergo in vitro fertilization (IVF) treatment to bypass fertilization in the fallopian tubes.

Group B strep

Group B streptococcus is a bacteria found in the vagina or rectum of almost 25 percent of healthy females. Routine testing for group B strep is done between the 35th and 37th week of pregnancy. Intravenous medications given during labor can prevent the mother from passing group B strep to her baby. About 1 in 200 babies who are born to mothers with group B strep will have group B strep. If a baby contracts group B strep during birth, he or she may experience:

  • Sepsis
  • Meningitis
  • Pneumonia
  • Breathing issues.

Rh negative disease

Rhesus isoimmunization is a protein that lies on the surface of red blood cells. Rh is a recessive gene and those who are Rh negative experience little to no effect on their health.

If an Rh-negative woman becomes pregnant by an Rh-positive man, the baby has a 75 percent chance of being Rh positive. If an Rh-negative woman is pregnant with an Rh-positive baby, her body may react as if it is allergic to the baby and build up antibodies against the baby. This is known as Rh incompatibility.

The most common complication from Rh negative disease is hemolytic anemia, a condition caused by Rh antibodies destroying the baby’s red blood cells faster than they can be reproduced. Babies experiencing hemolytic anemia may need to be delivered before 37 weeks or receive a blood transfusion in utero through the umbilical cord.

A simple test at the beginning of pregnancy can determine if the mother’s antibodies have affected the baby’s red blood cells. A shot of Rh immunoglobulin, a medication to neutralize the antibodies, is usually given around 28 weeks and at the time of birth.

An Rh-negative woman’s first Rh-incompatible pregnancy typically causes no complications because her body has not had sufficient time to build antibodies against the baby. An Rh-negative woman will need an Rh immunoglobulin shot with each subsequent pregnancy.


Women who have a larger body mass index (BMI) before pregnancy are more likely to experience pregnancy complications, need more prenatal visits and have longer hospital stays for delivery.

Common pregnancy complications caused by obesity are:

  • Preeclampsia
  • Cesarian section
  • Gestational diabetes
  • Still birth.

If an overweight or obese woman loses weight before pregnancy, she is more likely to have a healthy pregnancy with a lower risk of obesity-related pregnancy complications. Additionally, women who struggle with infertility and obesity may be able to increase their chance of a natural conception by losing weight under the guidance of a fertility doctor.

Gestational diabetes mellitus (GDM)

Pregnancy caused diabetes occurs when the body of the pregnant woman cannot metabolize sugars and carbohydrates. GDM can typically be controlled by a healthy diet and regular exercise. Some women may also need insulin shots to keep their blood sugar levels under control.

GDM left untreated is a serious condition that may cause additional pregnancy complications such as:

  • Preeclampsia
  • Preterm delivery
  • High birth weight babies, which can cause additional stress and birth complications
  • Cesarian section
  • Babies born with high blood sugar, breathing problems and jaundice.

Hyperemesis gravidarum (excessive nausea or vomiting)

For the first 12 weeks of pregnancy most women experience “morning sickness,” which can actually occur at any time of day. Physicians believe that the rapid increase of the pregnancy hormone human chorionic gonadotropin (HCG) causes nausea and vomiting early in pregnancy.

Hyperemesis gravidarum, however, can be a serious condition because excessive vomiting may lead to:

  • Dehydration
  • Weight loss
  • Loss of nutrients for both mother and baby.

Women experiencing hyperemesis gravidarum may experience relief from symptoms with a simple change in diet and the addition of 100mg of B12. Women with more severe cases may be prescribed an anti-nausea medication, which is safe for both mother and baby.