Fatty Liver and Pregnancy

Written by Hallie Levine
Medically Reviewed by Traci C. Johnson, MD on December 16, 2024
10 min read

Nonalcoholic fatty liver disease (NAFLD) is a medical condition where fat builds up in your liver. It’s a very common condition found in about a quarter of all American adults. But when it happens during pregnancy, it can cause serious complications for both the parent and their baby.

Doctors are in the process of renaming NAFLD to to metabolic dysfunction-associated steatotic liver disease (MASLD), due to concerns about how the disease is understood. Steatosis means a buildup of fat in an organ.

Yes, you can. As fatty liver disease becomes more common, more women enter pregnancy with it. A recent study found that NAFLD, a form of fatty liver disease, has nearly tripled in pregnant women over the past 10 years. It increases risks for both the parent and the baby, such as:

  • High blood pressure in pregnancy
  • Preeclampsia
  • Bleeding after delivery
  • Preterm birth

As a result, NAFLD is considered a high-risk condition in pregnancy. If you do have NAFLD and want to have a baby, you should receive preconception counseling to learn about these risks. 

 

There are two types of fatty liver that can happen in pregnancy. They are:

Acute fatty liver of pregnancy (AFLP). Acute fatty liver of pregnancy is very rare. It happens in less than one in 7,000 pregnancies each year. But it can be very serious. During AFLP, fat builds up in your liver. If it’s left untreated, it can lead to liver failure. It usually shows up in the third trimester, between your 30th and 38th weeks of pregnancy, although it can crop up as early as 18 weeks or as late as four days after delivery. To treat it, your doctor will want to have you give birth as soon as possible.

Nonalcoholic fatty liver disease (NAFLD). This is a condition where excess fat builds up in your liver. Unlike alcoholic fatty liver disease (AFLD), this isn’t caused by the consumption of too much alcohol. It’s likely due to not being at a healthy weight or having obesity, and to having conditions related to that. It’s estimated that 75% of people who are overweight, and up to two-thirds of people with type 2 diabetes, have NAFLD. You can have NAFLD when you enter pregnancy or develop it while you are pregnant. 

About one-third of American women in their 20s and 30s have obesity, so they may already have NAFLD when they get pregnant. They can also develop it during their pregnancy. When you’re pregnant, you’re more likely to develop insulin resistance, which in turn makes you more vulnerable to NAFLD.

If you have AFLP or NAFLD, you have too much fat in your liver. It builds up in your liver and clogs it up, which interferes with normal liver function. If it’s left untreated, it can lead to liver failure, and sometimes death.

The cause of each one is slightly different. AFLP appears to be due to a genetic disorder. During the last trimester of pregnancy, there is a big increase in substances called free fatty acids, which are a major source of fuel for your body and help your baby grow and develop. People with AFLP aren’t able to break down these fatty acids efficiently, due to mitochondrial dysfunction. The mitochondria are the powerhouses of your cells. They break down fatty acids into fuel that your body can use to process nutrients such as proteins, carbohydrates, and fat. But if you have AFLP, your mitochondria aren’t able to do their job. Free fatty acids build up in your blood and damage your liver cells so that they can’t remove toxins from your body. 

About 20% of cases of AFLP are due to a deficiency in the LCHAD enzyme. LCHAD helps your body break down fatty acids. Both parents must have a gene for LCHAD deficiency in order to pass it to their baby. If the fetus inherits both copies of LCHAD, they can’t break down fatty acids correctly. Instead, these fatty acids pass through the placenta and build up in the pregnant person’s blood and liver cells, where they cause damage. The most common gene mutation linked to LCHAD deficiency is G1528C. This variant is also linked to several other life-threatening pregnancy complications. These include preeclampsia and HELLP syndrome. 

You’re more at risk of getting AFLP if you:

  • Have never been pregnant before
  • Carry twins or more
  • Carry a male fetus
  • Have a BMI of under 20 (for a 5-foot-4-inch person who weighs less than 116 pounds)

There may also be certain gene mutations that make you more likely to get NAFLD. Other risk factors include:

  • Obesity or not being at a healthy weight 
  • Type 2 diabetes, or even prediabetes
  • Abnormal cholesterol or triglyceride levels
  • High blood pressure
  • A diet high in added sugars

Most symptoms of AFLP show up between the 30th and 38th weeks of pregnancy. They can also happen earlier or later. Early signs include:

  • Nausea
  • Throwing up
  • Stomach pain
  • Tiredness
  • Headache
  • Loss of appetite
  • High blood pressure

As symptoms get worse, you may have signs of liver failure such as:

  • Jaundice (yellowing of your skin or the whites of your eyes)
  • Encephalopathy, or brain changes that leave you confused or unable to focus
  • Swelling in your abdomen (belly area)
  • Blood clots

About 20% of people with AFLP go on to develop HELLP syndrome, and 20% to 40% will get severe preeclampsia. Unfortunately, sometimes symptoms aren’t recognized until the baby is in distress, or even dies. It’s important to be aware of some of the warning signs of AFLP, especially in the third trimester, and seek medical help as soon as possible. 

If you have NAFLD, you usually don’t have any symptoms. If you do, you may feel tired and/or have discomfort on the upper right side of your stomach. Symptoms that can show up at late stages, when you are in liver failure, include:

  • Itching
  • Swollen belly
  • Easy bruising and bleeding
  • Jaundice
  • Encephalopathy
  • Spider-like blood vessels right underneath your skin

If you do notice pain on the upper right side of your stomach, let your doctor know right away. It can also be a sign of HELLP syndrome, which can be fatal.

Acute fatty liver of pregnancy doesn’t develop until around the third trimester. But if you have risk factors such as not being at a healthy weight or having obesity or type 2 diabetes, you may already have a fatty liver and you just don’t know it.

People who are pregnant with NAFLD are at more risk of having certain complications, according to a recent study. The study looked at more than 18 million deliveries between 2012 and 2016. NAFLD was found in 5,640 pregnant people, while more than 115,000 had other chronic liver diseases. People with NAFLD were more than three times more likely to develop preeclampsia, eclampsia, or HELLP syndrome than people without the condition. They also found people with NAFLD were more likely to have:

  • Gestational diabetes (23% vs. 7% to 8%)
  • Postpartum hemorrhage (6% vs. 3% to 5%)
  • Preterm birth (9% vs. 5% to 7%)

People with NAFLD were also almost twice as likely to have a large birth weight baby. 

If you have risk factors for NAFLD and are pregnant, or plan to get pregnant, talk to your doctor. If they haven’t already diagnosed you with NAFLD, they may want to screen you for it. They may run blood tests to check your liver function. If those show elevated levels, they may recommend imaging tests such as an ultrasound, computed tomography (CT) scan, or magnetic resonance imaging (MRI) scan to see if you have fat in your liver. A new imaging test, elastography, measures the stiffness of your liver. A high score may mean you have liver fibrosis, or scar tissue, from NAFLD.

If you do have NAFLD, your pregnancy should be managed by a maternal-fetal medicine specialist. This is a doctor who handles high-risk obstetrics. They can monitor you closely throughout your pregnancy to ensure the best health for both you and your baby.

If you develop AFLP during pregnancy, your doctor will want you to deliver right away. This is true no matter how far along in your pregnancy you are. If you don’t have your baby, you could develop acute liver failure and die.

You’ll be hospitalized right away, possibly even admitted to the intensive care unit. During this time, doctors will run blood tests to monitor:

  • Your complete blood count (including white blood cells, red blood cells, and platelets)
  • Liver enzymes
  • Prothrombin time. This is a protein made by your liver to help your blood clot. 
  • Ammonia levels to check for liver failure
  • Blood glucose levels. People with AFLP often get hypoglycemia, or low blood sugar.

You will also be watched carefully for signs of encephalopathy. Your baby’s heart rate will be monitored all the time. If they show signs of distress, you may need to deliver your baby right away.

If you are less than 32 weeks pregnant, the hospital may give you magnesium sulfate through an IV for 24 hours before delivery. It reduces the risk of cerebral palsy or a brain bleed in your baby. 

Most of the time, your AFLP goes away once you give birth. Your doctors will run frequent blood tests to check your liver function. It usually returns to normal within a week to 10 days after delivery.

Your baby will need to be tested for LCHAD deficiency. It can be done as part of their newborn screening panel. A special machine measures how much of a substance called acylcarnitine is in your baby’s blood. High levels may mean they have LCHAD deficiency. If it’s positive, your baby will have follow-up testing where their urine and blood are checked for certain acids and toxins. If they do have LCHAD deficiency, they will need to be on a high-carbohydrate, low-fat diet. Their pediatrician may also prescribe medium chain triglyceride (MCT) oil to give the body fats it can break down, as well as L-carnitine supplements to help their body break down fats.

Babies who are diagnosed early with LCHAD deficiency, and get early treatment, can be healthy and have normal development. Some do go on to develop muscle and vision problems. 

Some people do develop AFLP again during a subsequent pregnancy. Your doctor may suggest genetic testing to see if you have a gene mutation linked to LCHAD deficiency. Even if you don’t have a gene mutation, you can still get AFLP again. You’ll be closely watched in future pregnancies. You may even need to be seen by a maternal-fetal medicine specialist. 

If you get pregnant and you have NAFLD, you should be under the care of a maternal-fetal medicine specialist. They will monitor you closely for signs of preeclampsia, eclampsia, and HELLP syndrome. Some doctors think people with NAFLD should take a daily low-dose aspirin through much of their pregnancy. This is already recommended for people with a history of either preeclampsia or premature delivery before 34 weeks. But studies need to be done to know for sure.

Fatty liver happens when too much fat builds up in your liver and makes it harder for it to do its job. Two types of fatty liver can happen during pregnancy: acute fatty liver of pregnancy (AFLP) and nonalcoholic fatty liver disease (NAFLD). Both can cause serious, life-threatening complications, both for you and for your baby. If you are diagnosed with AFLP, you will need to deliver your baby right away to prevent liver failure. If you have NAFLD, you’ll be monitored closely throughout your pregnancy for signs of life-threatening conditions such as preeclampsia, eclampsia, and HELLP syndrome. For both types of fatty liver disease, you’ll need to be under the care of a maternal-fetal medicine specialist, a type of doctor who handles high-risk obstetrics. 

Is it safe to get pregnant if you have fatty liver?

People who get pregnant and have NAFLD are more likely to have certain complications such as gestational diabetes, preeclampsia, eclampsia, or HELLP syndrome. They’re also more likely to give birth prematurely and to have complications after delivery such as a severe a postpartum hemorrhage. Your pregnancy should be managed by a maternal-fetal medicine specialist who can monitor you closely throughout your pregnancy.

If you develop fatty liver while pregnant, can you reverse it and remain pregnant?

You can’t reverse acute fatty liver, which you can develop during pregnancy (AFLP). The only treatment is to give birth right away. 

How can I cleanse my liver during pregnancy?

Your liver naturally cleanses itself, whether you’re pregnant or not. Its job is to convert toxins into waste products and break down important nutrients. You don’t need to do anything to cleanse it while you are pregnant. In fact, some advertised liver cleanses can harm both you and your unborn baby. To keep your liver healthy during pregnancy, it's best to avoid excessive weight gain and to not drink. Between pregnancies, make sure that you are at a healthy weight, since having obesity is linked to NAFLD.