Additional pregnancy complications include:

• Rh incompatibility. Rh factor is a substance found in red blood cells. Rh incompatibility can occur when a woman who is Rh-negative is exposed to Rh-positive blood cells from her fetus (most people are Rh-positive). This can occur during pregnancy, childbirth or amniocentesis testing. When this happens, the mother’s immune system begins to make antibodies against the Rh-positive blood cells, which can cross the placenta and damage the fetal blood cells. This condition, known as hemolytic disease or Rh disease, can cause death of the fetus. In a newborn, the disease may cause severe anemia, jaundice (yellowing of the skin and whites of the eyes), brain damage and heart failure. To prevent these complications, shots are typically administered to Rh-negative women during their first pregnancy around the 28^th week of gestation and within the 72 hours after delivery. This also will prevent the development of Rh antibodies in future pregnancies. In rare and severe cases, blood transfusions may be necessary while the fetus is still in the uterus or after delivery. An injection may also be administered prior to amniocentesis testing.
  
  
• Blighted ovum. Also known as an anembryonic pregnancy, a blighted ovum is a condition in which a fertilized egg develops a placenta and membrane but not an embryo. It can be caused by abnormal cell division or poor-quality sperm or egg. It typically occurs during the first few weeks of pregnancy, often before a woman is aware that she is pregnant. Diagnosis may occur when an ultrasound shows an empty uterus or an empty placenta. The condition usually results in miscarriage, though some women may choose dilation and curettage (D&C) to remove the placental tissue. The condition cannot be prevented, but women rarely experience a blighted ovum more than once.
  
  
• Incompetent cervix. As a fetus grows during pregnancy, its weight begins to press on the cervix. In a woman with an incompetent or weakened cervix, the cervix may open under the weight, leading to premature delivery or a miscarriage. The condition may be caused by previous damage to the cervix during surgery, a difficult birth or D&C. An incompetent cervix may also result from a birth defect or from diethylstilbestrol (DES) exposure. Incompetent cervix may be diagnosed through a pelvic exam or an ultrasound. To prevent complications, the cervix may be sewn closed during the pregnancy (cervical cerclage).
  
  
• Cholestasis. Characterized by severe itching, cholestasis is a condition in which bile excretion from the liver is blocked. The condition can be diagnosed with blood tests. When it occurs during pregnancy, it can increase the risk of fetal distress, premature birth or stillbirth. Labor may be induced once the fetus’ lungs have matured.
  
  
• Intrauterine growth retardation (IUGR). This term is used to describe a smaller than normal fetus (weighing below the 10^th percentile for gestational age). Because the baby does not grow at the normal rate, the condition typically results in a low birth weight (less than 5 pounds, 8 ounces, or 2,500 grams). Diagnosed by ultrasound, IUGR may result from a mother’s poor nutrition, heart disease, high blood pressure, preeclampsia, eclampsia, smoking, and drug or alcohol use. Insufficiency of the placenta, multiple pregnancy, high altitude, birth defects and genetic disorders can also lead to the condition. IUGR fetuses are at increased risk of intrauterine death. As a result, the fetus may be monitored and early delivery may be recommended.
  
  
• Urinary tract infection. An infection occurring along the urinary tract, which includes the kidneys, bladder, ureters and urethra. The condition is diagnosed with a urine test and can be successfully treated with antibiotics. Left untreated, the infection can spread to the kidneys, resulting in premature labor.
  
  
• Hyperemesis gravidarum. This is a condition characterized by frequent and severe vomiting. It is a concern during pregnancy because it may lead to dehydration (a depletion of body fluids). It may also interfere with the weight gain needed to supply adequate nutrition to the mother and fetus. Medication may be prescribed to reduce nausea and vomiting. In severe cases, the mother may require hospitalization and intravenous (I.V.) fluids to balance the level of electrolytes in the blood. Treatment may also require fasting, followed by a slow introduction of food back into the diet.
  
  
• HELLP syndrome. Left untreated, preeclampsia can lead to HELLP syndrome, a condition characterized by hemolysis (the destruction of red blood cells), elevated liver enzymes and a low platelet count. Women can also develop the condition without preeclampsia two to seven days after delivery. According to the Preeclampsia Foundation, HELLP syndrome occurs in 4 to 12 percent of women with preeclampsia. It can lead to liver failure and coagulation (blood clotting) disorders, and poses a high risk of death for the mother and her fetus.
  
  
• Eclampsia. Although it occurs rarely, preeclampsia can progress into a condition known as eclampsia. A serious condition, eclampsia is characterized by the occurrence of seizures. The condition can lead to coma and death of the expectant mother and her fetus.
  
  
• Pre-existing diabetes. When their glucose (blood sugar) levels are kept within a normal range before and during pregnancy, pregnant women with pre-existing diabetes are almost as likely as women without the condition to deliver a healthy baby. But when glucose levels are not kept under control, there is an increased risk for miscarriage, stillbirth and birth defects. To prevent complications, pregnant women with pre-existing diabetes may be advised by their physician to take insulin to control their glucose levels. A multivitamin and folate may also be recommended to help prevent birth defects.