As your due date gets closer, some aches, swelling, and strange symptoms can feel like just another part of late pregnancy. But certain changes — including severe headaches, sudden swelling, vaginal bleeding, blurred vision, fever, or a noticeable change in your baby’s movement — can be signs of serious complications. Knowing which symptoms shouldn’t be ignored can help you get care quickly and keep both you and your little one safer during the final stretch of pregnancy.

But how can you tell the difference between “normal” extremes and late pregnancy warning signs? Late pregnancy comes with the risk of some serious complications, including:

There's no need to sit around worrying, but it is important to be aware of red flags that could mean something is wrong and you need to take action.

These are some of the serious late pregnancy warning signs and symptoms that every mom-to-be should know about, plus how to reduce your risk for complications — and how the problems can be treated if they do occur. 

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Key Takeaways
  • Know what’s normal (and what’s not). Late pregnancy can bring plenty of aches and surprises, but certain symptoms may signal something more serious and shouldn’t be ignored.
  • Watch for key warning signs. Symptoms like vaginal bleeding, severe headaches, sudden swelling, or changes in your baby’s movement are your cue to call your health care provider.
  • Stay on top of your care. Regular prenatal checkups and understanding your personal risk factors can help catch potential complications early and keep you and your little one safe.
  • Focus on what you can control. While not all complications are preventable, healthy habits, staying proactive, and keeping open communication with your doctor can go a long way in supporting a safer, smoother final stretch.

What are late pregnancy warning signs to look out for?

Discomfort is par for the course as you near the end of your pregnancy. (Hello, lightning crotch and back pain!) But it’s important to know the difference between those normal third trimester woes and signs of potential complications, including preeclampsia, eclampsia, HELLP, and complications related to heart conditions.

The main late pregnancy warning signs to watch out for are:[1]

These are some of the most common warning signs of something more serious. But you know your body best. If you experience something else that seems unusual or worrying, don’t ignore it.

"I went to the hospital because of extreme swelling in my feet and legs," shares What to Expect Community member jvall089, who was then diagnosed with preeclampsia at a follow-up appointment.

When should you see a doctor about late pregnancy warning signs?

If you notice the above symptoms, call your health care provider right away, even if it’s after hours. Your doctor or midwife can help you figure out next steps based on your symptoms and health history. 

"I went in last week for a pretty severe headache and what I thought was amniotic fluid leaking," shares Community mom esumom23. "Labs came back perfect, and no leakage. The nurses told us they would rather I come in and be okay than not."

You’ll likely see your practitioner twice a month from week 28 to 36, and once a week from 36 weeks until your baby is born. Staying on top of those routine prenatal checkups is crucial, since they can help spot potential problems early and keep you and your sweet pea healthy.

Those checkups are your built-in reassurance checkpoints — and the What to Expect app helps you stay organized between them, with reminders, personalized tips, and a clear look at what’s coming next for you and your growing little one.

But that’s not all. The American College of Obstetricians and Gynecologists (ACOG) issuedupdated prenatal care guidelines in recent years to help protect against heart disease and related heart complications, which have affected a growing number of moms-to-be.

Here’s what you should know, according to ACOG:[2]

  • All women should be assessed for cardiovascular disease during their pregnancies.
  • Women with moderate- to high-risk heart disease should be evaluated by a cardiologist and managed during pregnancy, delivery, and postpartum at a medical center that can provide a higher level of care.

That might sound like a lot, but it’s important. If you have heart disease or related risk factors that could stress your heart (like high blood pressure), taking steps to address them up-front can help minimize the risk for serious complications during your pregnancy as well as postpartum.

What are some risk factors and causes of late pregnancy complications?

Late pregnancy problems and complications have a number of different causes. The best way to protect your health is by understanding your individual risk factors and talking about them with your doctor. Some of the most common ones include:[3]

For heart disease and related heart conditions:

  • Being non-Hispanic Black
  • Being over 40
  • Being obese
  • Having high blood pressure, including high blood pressure problems related to pregnancy like preeclampsia
  • Having gestational diabetes (especially if you've been prescribed a medication to manage it)
  • Having obstructive sleep apnea
  • Having a history of preterm delivery or a family history of heart disease
  • Exposure to cardiotoxic drugs

For preeclampsia and eclampsia: 

  • Being Black or Indigenous
  • Being obese
  • Being over 35 at the time of delivery
  • Having gestational high blood pressure
  • Having a preexisting health problem like diabetes, lupus, rheumatoid arthritis, scleroderma, sickle cell disease, thrombophilia or polycystic ovary syndrome (PCOS)
  • Being pregnant with multiples
  • Getting pregnant via in vitro fertilization (IVF)
  • Being deficient in vitamins E, C, or magnesium, or being deficient in vitamin D in the first 26 weeks of pregnancy

For HELLP syndrome:

  • Having pregnancy-induced high blood pressure, preeclampsia, or eclampsia

How are serious late pregnancy symptoms treated?

If you’re at high risk for late pregnancy complications, your doctor might recommend preemptive steps like frequent monitoring and testing based on your risk factors. If you have a risk of heart problems, you might need to see a cardiologist to determine the best treatment options.

As for preeclampsia and HELLP? The cure for these conditions begins with giving birth. (You'll want to remain vigilant for signs of postpartum preeclampsia after your baby arrives.) Your doctor will recommend steps to manage the problem in the meantime based on your symptoms. 

Gestational diabetes or preeclampsia that's not severe may be manageable at home with:

  • Regular blood and urine tests
  • Daily kick counts
  • Blood pressure monitoring
  • Drinking more water, eating more protein, and eating less salt
  • Bed rest on your left side

Severe preeclampsia is usually treated at the hospital with:

  • Regular fetal monitoring
  • Blood pressure-lowering medications
  • Electrolytes like magnesium sulfate
  • Early delivery via induction, if you’ve reached 34 weeks

"My OB/GYN is scheduling me for a 37-week induction due to my history of preeclampsia, and my blood pressure has been wild with ups and downs," says a What to Expect Community member Wild-FlowerDreams.

HELLP is usually treated at the hospital with:

  • Blood pressure medication, magnesium sulfate and corticosteroids if you’re less than 34 weeks pregnant
  • Early delivery via induction, if you’ve reached 34 weeks

Is there any way to prevent complications in late pregnancy?

There’s no way to guarantee a complication-free pregnancy. But there are plenty of things you can do to reduce your risk as much as possible, including following these tips:

  • Be proactive. Share your health history with your doctor and keep up with your prenatal appointments. And if you notice any unusual symptoms, let your doc know! You know your body best, so if something seems off to you, speak up.
  • Eat right. Fill up on fruits and veggies, whole grains, low-fat dairy, and lean proteins.
  • Exercise. You’ll want to get the green light from your doctor first. But in general, it’s worth doing 30 minutes of moderate activity (like brisk walking) every day.
  • Aim for steady, healthy weight gain. Gaining the right amount for your body and pregnancy can support both you and your baby.
  • Ask about aspirin. Your doctor might recommend a daily low-dose aspirin regimen, which may protect against complications like preeclampsia, especially if you had preeclampsia or gestational hypertension in a prior pregnancy or are in certain high-risk group categories.
  • Brush and floss daily. Some research has indicated that women with a history of periodontal disease are at increased risk for preeclampsia. So to be on the safe side, maintain good oral hygiene.
  • Take your prenatal vitamin. Some vitamin and mineral deficiencies are tied to a higher preeclampsia risk.

Having preeclampsia has been linked to an increased risk for high blood pressure, cardiovascular disease, stroke, and kidney disease later in life, especially in women who were diagnosed with the condition in two or more pregnancies or had preeclampsia that required delivery before 34 weeks of pregnancy.

That's why it's important to talk to your doctor about steps you can take to reduce your risk of these conditions long after you deliver, including lifestyle changes like following a heart-healthy diet and getting more exercise.

Late pregnancy can come with the risk of some serious complications. While you shouldn’t spend those final, special weeks constantly worrying about your health, it’s worth being proactive.

So stay on top of your prenatal care, keep in touch with your doctor and pay attention to potential warning signs. And hang in there. Before you know it, your baby will be here.