What Is HELLP Syndrome?

HELLP syndrome is often considered to be a variant of preeclampsia, which is marked by the development of high blood pressure during pregnancy (usually after the 20th week) or in the postpartum period (1, 2). However, HELLP may actually be a distinct condition. Although HELLP syndrome and preeclampsia are closely linked, it is possible for an expectant mother to have HELLP syndrome without having high blood pressure or other signs of preeclampsia, such as an excess of protein in the urine (3).

Physician Louis Weinstein named HELLP syndrome after the following characteristics:

• H – Hemolysis. This means that red blood cells are broken down too quickly. This can lead to anemia, a problem involving insufficient transport of oxygen throughout the body.
• EL – Elevated liver enzymes.  This can be taken as a sign that liver function is compromised.
• LP – Low platelet count. Platelets help with blood clotting, so an unusually low level of platelets indicates that a person is at risk for excessive bleeding (2, 4).

HELLP syndrome is a relatively rare complication, affecting approximately 0.1 to 0.2 percent of all pregnancies. However, about 10 to 20 percent of women with severe preeclampsia (or eclampsia, which occurs when preeclampsia causes seizures and other extremely dangerous complications) also develop HELLP (5).

Women with the following risk factors are more likely to develop HELLP:

• HELLP syndrome in a prior pregnancy
• Preeclampsia/eclampsia in a prior pregnancy or in the current pregnancy
• Having previously given birth (interestingly, not having previously given birth is a risk factor for preeclampsia/eclampsia)
• Caucasian
• Age over 25 (1)

The exact causes of HELLP syndrome are unknown, but we do have some information. When linked to preeclampsia, HELLP is probably due to issues with the development and function of the placenta. It can also be caused by abnormal placentation, or the positioning of the placenta in the mother’s uterus. Very occasionally (in less than 2 percent of patients), HELLP can be partially attributed to a deficiency in fetal long-chain 3-hydroxyacyl CoA dehydrogenase (LCHAD).

HELLP syndrome can manifest differently in different patients. The most common symptom is abdominal pain and tenderness (5), which generally occurs in the upper right abdomen (1). Other symptoms of HELLP include the following:

• High blood pressure
• High levels of protein in the urine
• Nausea and vomiting
• Headaches
• Malaise
• Exhaustion
• Vision problems (such as blurry vision)
• Jaundice
• Swelling
• Weight gain
• Seizures
• Bleeding that does not easily stop (this may include nosebleeds) (1, 2, 5).

Usually, signs and symptoms of HELLP syndrome emerge between 28 and 36 weeks of pregnancy, but it may occur earlier. Some women also develop HELLP syndrome shortly after giving birth (5).

HELLP syndrome is sometimes misdiagnosed, especially in women who do not have high blood pressure or an excess of protein in their urine. Women with HELLP syndrome may be incorrectly diagnosed with conditions such as gastritis, acute hepatitis, appendicitis, gallbladder disease, a bleeding disorder, or even the flu (1, 2, 5). Although the most obvious symptoms of HELLP syndrome are similar to those of many other health issues, physicians can use the following tools in order to make a diagnosis:

• Blood tests
• Urine tests
• Blood pressure measurements
• CAT scan (which can show bleeding into the liver)

The appropriate medical management of HELLP syndrome varies based on the severity of the mother’s symptoms, as well as the gestational age of the baby (i.e., how long the mother has been pregnant). Often, the baby should be promptly delivered. Most experts agree that delivery is indicated in the following circumstances:

• Gestational age of <23 weeks or ≥34 weeks
• The baby has died
• The baby is showing signs of fetal distress
• The mother’s health depends on prompt delivery.

Between 23 and 34 weeks of gestation, doctors generally evaluate the baby’s lung function to determine how well they would handle delivery (5).

Prior to delivery, the following measures may be taken to protect the health of the mother and baby:

• Bed rest
• Close monitoring of maternal and fetal conditions
• Blood pressure medications
• Blood transfusion (this may be necessary if platelet count is dangerously low)
• Corticosteroid administration to help prepare the baby’s lungs for the outside world
• Magnesium sulfate in order to prevent seizures

A Cesarean section used to be the recommended method of delivering babies in cases of HELLP syndrome. However, the American Pregnancy Association now recommends that women be given a trial of labor if they have a favorable cervix, are at least 34 weeks into their pregnancy, and there are no other complications (maternal or fetal) that would necessitate a Cesarean delivery. The Association makes this recommendation because women with HELLP syndrome may experience blood clotting problems if they have an operation (1).

If doctors fail to diagnose or treat HELLP syndrome, the mother and/or baby can experience life-threatening complications. The mother is at risk for the following:

• Placental abruption
• Blood clotting issues that can result in maternal hemorrhage
• Pulmonary edema (a buildup of fluid in the lungs)
• Lung failure
• Acute renal failure
• Rupture of the liver
• Stroke
• Death (1, 4)

These problems can also seriously affect the baby. Infants born to mothers with HELLP syndrome may have a variety of birth injuries:

• Intrauterine growth restriction (IUGR)
• Severe respiratory distress
• Intraventricular hemorrhage (IVH)
• Perinatal asphyxia and hypoxic-ischemic encephalopathy (HIE)
• Heart problems
• Other complications associated with premature birth, such as infection, anemia, apnea, and bradycardia (1, 4, 6)