What is HELLP syndrome?
HELLP syndrome is a rare, serious complication of pregnancy that affects the liver and the blood's clotting system. The name is an acronym for its three hallmark features: Hemolysis (the breakdown of red blood cells), Elevated Liver enzymes, and Low Platelet count. It usually develops in the third trimester, though it can appear earlier, and occasionally even in the days after delivery. It's closely linked to preeclampsia — a pregnancy condition involving high blood pressure and organ strain — though some people develop HELLP without ever having high blood pressure recorded.
HELLP syndrome is uncommon overall, but it's more frequent among people who already have preeclampsia. It's considered a medical emergency because it can progress quickly and affect major organs, including the liver, kidneys, and blood clotting system. The reassuring part is that it's well recognized by obstetric providers, and with prompt diagnosis and treatment — usually delivery — most people recover fully. Getting checked when something feels wrong makes a real difference to how it plays out.
What causes HELLP syndrome, and who's at risk?
The exact cause of HELLP syndrome isn't fully understood, but it's thought to involve problems with how the placenta develops and how blood vessels respond throughout the body. These changes can affect the liver and trigger the breakdown of red blood cells and platelets — the same underlying process seen in severe preeclampsia. Because of this overlap, HELLP is generally considered a variant or complication of preeclampsia rather than a separate condition, even though it can occur without the high blood pressure that usually defines preeclampsia.
Certain factors raise the likelihood of developing HELLP syndrome, though it can also occur in people with none of them. Risk factors include a personal or family history of preeclampsia or HELLP, being over 35, carrying multiples (twins or more), having chronic high blood pressure or an autoimmune condition, and having had HELLP in a previous pregnancy. Still, many people who develop HELLP have straightforward, low-risk pregnancies up to that point — it isn't something you can predict or prevent through diet or lifestyle.
What are the symptoms of HELLP syndrome?
The most common symptoms of HELLP syndrome are pain in the upper right side of your abdomen or in your chest, nausea or vomiting that feels different from typical pregnancy sickness, a bad headache that doesn't go away, and a general feeling of being unwell or unusually tired. Some people also notice swelling in the hands or face, blurred vision, or bleeding that's hard to stop. Symptoms can develop gradually over a day or two, or quite suddenly, and not everyone has every symptom.
Call your midwife or doctor the same day — or go to the emergency room — if you have upper abdominal or chest pain, a severe or persistent headache, vision changes, sudden swelling, or vomiting that won't stop, especially after 20 weeks of pregnancy. These symptoms can also appear in the days after delivery, so the same rule applies postpartum. Don't wait to see if it passes on its own; HELLP syndrome can worsen quickly, and being checked costs you nothing if it turns out to be something else.
How is HELLP syndrome diagnosed?
HELLP syndrome is diagnosed through blood tests that check for its three defining features: a blood smear showing hemolysis, liver function tests showing elevated liver enzymes, and a platelet count that's lower than normal. Your provider will usually also check your blood pressure and test your urine for protein, since HELLP overlaps closely with preeclampsia. There's no single test result that confirms HELLP on its own — the diagnosis comes from the whole pattern, together with your symptoms.
Because early symptoms — nausea, fatigue, a headache — can look like ordinary pregnancy discomfort, HELLP is sometimes missed at first or mistaken for something like the flu or gallbladder trouble. If your symptoms don't fit your usual pattern, or you have any of the warning symptoms above, ask specifically to be checked for preeclampsia and HELLP. Providers take these symptoms seriously in the third trimester and will usually run blood work quickly if you raise the concern.
How is HELLP syndrome treated?
The main treatment for HELLP syndrome is delivering the baby, because the condition is driven by the placenta and generally resolves once the placenta is removed. Your care team will weigh your baby's gestational age against how unwell you are. If you're far from term and both you and your baby are stable, they may try to buy a little more time with close monitoring; if either of you is at risk, delivery usually happens promptly regardless of gestational age.
Alongside delivery planning, treatment often includes medication to control blood pressure, magnesium sulfate to prevent seizures (a complication called eclampsia), and sometimes steroids to help your baby's lungs mature if delivery needs to happen early. You may need blood or platelet transfusions if your counts are very low. Care usually happens in a hospital with close monitoring of your blood pressure, blood tests, and your baby's wellbeing, often with input from both obstetric and maternal-fetal medicine specialists.
What does HELLP syndrome mean for your baby?
Babies born to mothers with HELLP syndrome are often born early, either because labor is induced or because a C-section is needed to protect both of you. Depending on how early delivery happens, your baby may need time in the neonatal intensive care unit (NICU) for breathing support or help feeding — this is standard care for premature babies, not a sign that something else is wrong. Babies can also be smaller than expected if the placenta wasn't supplying nutrients as well as usual.
Most babies born to mothers treated for HELLP syndrome do well, especially with the neonatal care available in modern hospitals. The specific outlook depends heavily on gestational age at birth and how HELLP was affecting the placenta before delivery — your obstetric team and, if needed, a neonatologist can talk you through what to expect for your particular situation. It's a genuinely hard thing to go through, and it's fair to want clear information rather than vague reassurance.
What happens after delivery, and could it happen again?
HELLP syndrome usually starts improving within a few days after delivery, though liver enzymes and platelet counts can take one to two weeks to fully return to normal. You'll likely stay in the hospital for closer monitoring than usual after birth, and your blood pressure and blood work will be rechecked before you go home and again at follow-up visits. Some people need blood pressure medication for a few weeks postpartum even after the underlying HELLP has resolved.
If you've had HELLP syndrome once, there's a real chance — though far from a certainty — of it recurring in a future pregnancy, and your provider will likely recommend earlier and more frequent monitoring next time, sometimes including low-dose aspirin starting in the first trimester. Having HELLP also raises your longer-term risk of high blood pressure and cardiovascular disease later in life, which is worth mentioning at future check-ups, not just future pregnancies. None of this means a future pregnancy will follow the same path — it means your care team will be watching more closely from the start.