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Preeclampsia warning signs with gestational diabetes

Call your ob-gyn right away if you have a headache that will not go away, changes in your vision, pain in the upper belly or shoulder, sudden swelling of your face or hands, sudden weight gain, new nausea and vomiting in the second half of pregnancy, or trouble breathing. Preeclampsia is more common with gestational diabetes, and it can also start in the weeks after birth.

Last reviewed 2026-10-20. Written by the First Fork team from the published guidelines listed below; not reviewed by a clinician. This page is not medical advice.

Why it matters with gestational diabetes

Preeclampsia is more common in people with gestational diabetes, and so is high blood pressure in pregnancy.1 Preeclampsia is high blood pressure together with signs that organs such as the liver or kidneys are affected. It usually starts after 20 weeks of pregnancy, most often in the third trimester, and it can also start in the weeks after birth.2

It can develop quietly. Many people with preeclampsia do not feel sick,5 and a high blood pressure reading may be the first sign. That is why your blood pressure is checked at every prenatal visit.2

Treating gestational diabetes helps. In a US trial of 958 women with mild gestational diabetes, preeclampsia and high blood pressure of pregnancy (counted together) were less common in the treated group than with usual care: 8.6% against 13.6%.3 Treatment lowers the risk. It does not remove it, so the signs below still matter.

The warning signs

SignWhat it can look like
A headache that will not go awayIt does not ease with medicine or fluids, or it gets worse. It may come with blurry vision or dizziness.24
Changes in your visionBlurry vision, seeing spots, seeing double, or not being able to focus.24
Pain in the upper belly or shoulderOften under the ribs on the right side. It is easy to mistake for heartburn or the baby kicking.25
Sudden swelling of your face or handsRings that suddenly will not go on, fingers that are hard to bend, or eyes that look puffy.24
Sudden weight gainMore than 3 to 5 pounds (about 1.4 to 2.3 kg) in one week.5
Nausea and vomitingNew and sudden in the second half of pregnancy, after morning sickness had already stopped.25
Trouble breathingShort of breath, new or getting worse.24
A high blood pressure reading140/90 or higher is high. 160/110 or higher is in the severe range.25

What to do

  1. Call your ob-gyn right away. Do not wait for your next visit, and do not sleep on it. ACOG says to call right away for any of these signs, especially in the second half of pregnancy.2
  2. If you cannot reach them, go in. The CDC lists most of these as urgent maternal warning signs and says to get medical care immediately.4 Go to labor and delivery or an emergency room. If it feels like an emergency, call 911.
  3. Say you are pregnant, or were pregnant in the last year,4 and that you have gestational diabetes.

Not sure if it is serious? Call anyway. The CDC says to talk to your provider when something does not feel right, even if it is not on a list.4

Normal swelling and warning swelling

Some swelling in the feet and ankles is normal in pregnancy.5 Swelling that comes on suddenly in your face or hands is different: it is a warning sign.24

Swelling, pain or tenderness in one leg, usually the calf, is a separate urgent sign. The CDC lists it from pregnancy up to 6 weeks after birth.4

After the baby is born

Preeclampsia can also start in the weeks after birth.2 The CDC's urgent warning signs apply for a full year after birth.4 Keep the signs above in mind after you go home.

Write it down next to your readings

When you call, your team will ask when it started. Write the day, the time and the sign in a few words next to that day's blood sugar readings. The free printable log has a notes column. In First Fork, each meal entry has a note next to the reading. Call first; write it down after.

Questions

Does gestational diabetes cause preeclampsia?

It makes preeclampsia more common. ACOG lists preeclampsia and high blood pressure among the problems that happen more often with gestational diabetes.

Can I have preeclampsia and feel fine?

Yes. It can develop with no symptoms, and a high blood pressure reading may be the first sign. Go to every prenatal visit, where your blood pressure is checked.

What blood pressure is too high in pregnancy?

140/90 or higher is high. 160/110 or higher is in the severe range. Ask your ob-gyn which home reading means you should call.

Can preeclampsia start after birth?

Yes, in the weeks after childbirth. The CDC lists urgent warning signs for the whole year after birth.

Does keeping my blood sugar in range prevent preeclampsia?

It lowers the risk but does not remove it. In a US trial of mild gestational diabetes, treatment lowered preeclampsia and high blood pressure of pregnancy (counted together) from 13.6% to 8.6%. Keep watching for the signs.

Sources

  1. ACOG. Gestational Diabetes (FAQ 177, reviewed April 2026). https://www.acog.org/womens-health/faqs/gestational-diabetes
  2. ACOG. Preeclampsia and High Blood Pressure During Pregnancy (patient FAQ). https://www.acog.org/womens-health/faqs/preeclampsia-and-high-blood-pressure-during-pregnancy
  3. Landon MB, et al. A multicenter, randomized trial of treatment for mild gestational diabetes. N Engl J Med 2009;361:1339–1348. https://pmc.ncbi.nlm.nih.gov/articles/PMC2804874/
  4. CDC, Hear Her campaign. Urgent Maternal Warning Signs and Symptoms (May 15, 2024). https://www.cdc.gov/hearher/maternal-warning-signs/index.html
  5. Preeclampsia Foundation. Signs and Symptoms. https://www.preeclampsia.org/signs-and-symptoms

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