How does diabetes affect pregnancy? High blood sugar can affect both the pregnant person and the baby. The Centers for Disease Control and Prevention (CDC) says that for people with type 1 or type 2 diabetes, high blood sugar around conception raises the risk of birth defects, stillbirth, and preterm birth. With any type of diabetes, high blood sugar during pregnancy raises the chance of a cesarean delivery and of the baby being born too large. The good news is that planning, close care, and blood sugar in the target range lower these risks. MedlinePlus says that with good control, most pregnancies have good outcomes.
Key takeaways
- Diabetes in pregnancy comes in two main forms: diabetes you had before pregnancy (type 1 or type 2) and gestational diabetes, which starts or is first found during pregnancy.
- CDC says about 1% of U.S. women with a live birth in 2016 had type 1 or type 2 diabetes, and about 8% of women with a live birth in 2021 developed gestational diabetes.
- The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) says a baby's organs start forming in the first 8 weeks, which is why blood sugar before conception matters so much.
- The American Diabetes Association (ADA) recommends planning pregnancy with your care team, including a medicine review, an eye exam, and blood sugar as close to normal as is safely possible.
- Insulin needs change through pregnancy and drop quickly after birth. Follow-up after delivery matters for every type.
Diabetes Before Pregnancy vs. Gestational Diabetes
There are two main ways diabetes shows up in a pregnancy. NIDDK says it is important to find out which one you have, because they are managed differently.
| Type 1 or type 2 diabetes (before pregnancy) | Gestational diabetes | |
|---|---|---|
| When it starts | Before pregnancy | Starts or is first found during pregnancy |
| Main early concern | High blood sugar in the first weeks, when organs form | Usually develops around the 24th week, according to CDC |
| How common | About 1% of U.S. live births in 2016 (CDC) | About 8% of U.S. live births in 2021 (CDC); CDC also cites 5% to 9% of pregnancies each year |
| After birth | Diabetes continues; insulin needs drop quickly | ACOG says it goes away after childbirth, but risk of type 2 diabetes stays higher |
CDC notes that high blood sugar found early in pregnancy may mean type 1 or type 2 diabetes, not gestational diabetes. Some people have type 2 diabetes and do not know it until pregnancy testing finds it. For an overview of every type, see how many types of diabetes there are.
How High Blood Sugar Affects the Baby
CDC, MedlinePlus, and the American College of Obstetricians and Gynecologists (ACOG) describe these possible effects when blood sugar runs high:
- Birth defects. NIDDK says a baby's brain, heart, kidneys, and lungs start forming in the first 8 weeks. High blood sugar at this early stage raises the chance of birth defects. This risk applies mainly to diabetes that was present before pregnancy.
- A larger baby. ACOG explains that extra sugar passes to the baby, who can gain a lot of weight. A baby of 9 pounds or more can lead to a harder delivery and a higher chance of shoulder injury during birth.
- Low blood sugar after birth. MedlinePlus says the baby is more likely to have low blood sugar in the first few days of life and may need care in the neonatal intensive care unit (NICU).
- Breathing problems and jaundice. ACOG lists both for babies born to people with gestational diabetes.
- Stillbirth and preterm birth. CDC lists both as risks of high blood sugar around conception for people with type 1 or type 2 diabetes. ACOG says gestational diabetes also raises the risk of stillbirth.
- Later health. CDC says high blood sugar during pregnancy raises a baby's risk of obesity or type 2 diabetes in the future.
These are risks, not certainties. They are the reason your care team checks you and your baby more often.
How Diabetes Affects the Pregnant Person
Pregnancy also changes how diabetes behaves in your own body:
- Higher blood pressure and preeclampsia. NIDDK says diabetes puts you at risk of preeclampsia, a serious blood pressure problem in pregnancy. ACOG says high blood pressure and preeclampsia are more common with gestational diabetes too. ADA recommends that clinicians prescribe low-dose aspirin, starting at 12 to 16 weeks, to lower preeclampsia risk in people with type 1 or type 2 diabetes. Only take aspirin if your clinician prescribes it. Our guide to blood pressure goals for people with diabetes covers goals outside pregnancy.
- Eye and kidney changes. NIDDK says pregnancy can make eye, heart, and kidney disease worse, especially when blood sugar is high. ADA recommends a dilated eye exam before pregnancy and in the first trimester for people with diabetes that started before pregnancy. See how often people with diabetes need an eye exam.
- Lows early, highs later. ADA says insulin sensitivity can be higher in early pregnancy, followed by rising insulin resistance in the second and third trimesters. NIDDK says insulin needs may double or even triple near the due date, then drop quickly after birth. ADA notes that people with type 1 diabetes have a higher risk of low blood sugar in the first trimester and after delivery.
- Ketoacidosis at lower blood sugar. ADA says pregnancy is a ketogenic state, and people with type 1 diabetes, and to a lesser extent type 2 diabetes, can develop diabetic ketoacidosis (DKA) at lower blood sugar levels than when not pregnant. Learn more about euglycemic DKA.
- Cesarean birth. CDC says high blood sugar during pregnancy raises the chance of a cesarean delivery with any type of diabetes.
Planning a Pregnancy With Type 1 or Type 2 Diabetes
ADA and NIDDK both say pregnancy should be planned when you have diabetes. ADA says preconception counseling is highly effective in lowering the risk of birth defects, preterm delivery, and NICU stays. ADA's 2026 guidance includes these steps:
- Talk with your care team early. ADA recommends starting preconception counseling at puberty and continuing it through the years when pregnancy is possible. Use effective birth control until you are ready.
- Work toward a target A1C. ADA says an A1C below 6.5% before pregnancy, if it can be reached safely without too many lows, is linked to the lowest risk of birth defects, preeclampsia, and preterm birth. Your care team sets your personal goal. See what A1C is considered diabetic for what A1C measures.
- Review every medicine. ADA says some glucose-lowering, cholesterol-lowering, and blood pressure medicines are not approved for use in pregnancy. Your prescriber plans if and when any change happens. Do not stop a medicine on your own.
- Ask about a prenatal vitamin. ADA recommends a prenatal vitamin with folic acid before conception. Ask your clinician which one fits you.
- Check your eyes, thyroid, and kidneys. ADA lists a dilated eye exam and thyroid screening among preconception steps. NIDDK says your team may check your kidneys early in pregnancy.
- Meet a dietitian. NIDDK says your care team may refer you to a registered dietitian to plan what, how much, and when to eat.
If you have type 2 diabetes and are planning ahead, our guide to whether people with type 2 diabetes need insulin explains why insulin is so common in pregnancy.
Blood Sugar Targets During Pregnancy
ADA lists these glucose goals for pregnant people with type 1 or type 2 diabetes. ADA notes they are similar to ACOG's goals.
| Check | ADA 2026 goal |
|---|---|
| Fasting | Below 95 mg/dL |
| 1 hour after a meal | Below 140 mg/dL |
| 2 hours after a meal | Below 120 mg/dL |
| A1C | Ideally below 6%, or below 7% if needed to prevent lows |
ADA says these goals are adjusted for each person to avoid low blood sugar. Your care team sets your targets. Gestational diabetes uses similar targets, covered in our guide to how gestational diabetes is treated.
How Diabetes Is Managed During Pregnancy
CDC says managing diabetes in pregnancy means seeing your doctor as recommended, checking your blood sugar, following an eating plan made with your doctor or dietitian, staying active, and taking insulin if directed.
- Insulin. ADA says insulin is the preferred medicine for type 1 and type 2 diabetes in pregnancy. ADA says metformin and glyburide should not be used as first-line medicines in pregnancy because both cross the placenta, and other diabetes pills and non-insulin shots lack long-term safety data. Any change is your prescriber's decision.
- Continuous glucose monitoring (CGM). ADA recommends CGM for pregnant people with type 1 diabetes and says it may also help with other types of diabetes in pregnancy.
- Ketone checks. NIDDK says your care team may ask you to check your urine for ketones at home. See ketones in urine.
- Team care. NIDDK lists a diabetes doctor, an obstetrician with diabetes experience, a diabetes educator or dietitian, specialists for eye, kidney, and heart health, and counselors who help with stress as possible members of your team.
Gestational Diabetes: The Other Side of the Picture
Gestational diabetes develops in people who did not have diabetes before pregnancy. ADA says hormones from the placenta can block insulin. ACOG says that most of the time the body makes extra insulin to keep up, but in some people it cannot, and blood sugar rises. We cover this in three companion guides:
- What causes gestational diabetes: placental hormones, insulin resistance, and who is more likely to get it
- How gestational diabetes is treated: eating, activity, blood sugar checks, and insulin
- Whether gestational diabetes goes away after pregnancy: postpartum testing and type 2 risk
For signs and screening, see our guide to gestational diabetes symptoms.
After the Baby Is Born
- Insulin needs drop. ADA says insulin resistance falls sharply right after delivery, so insulin doses need to be reviewed. Ask your care team for a plan before you go into labor.
- Breastfeeding. ADA recommends breastfeeding efforts for everyone with diabetes. For people taking insulin, ADA advises extra attention to preventing lows around breastfeeding and erratic sleep and meals.
- Postpartum testing. CDC says to get tested for diabetes 4 to 12 weeks after birth if you had gestational diabetes, and every 1 to 3 years after that.
- Mental health. CDC says gestational diabetes may raise the risk of postpartum depression. If you or someone you know is struggling or in crisis, CDC lists the National Maternal Mental Health Hotline at 1-833-TLC-MAMA (1-833-852-6262). Read more about diabetes and depression.
When to Call Your Care Team
Call 911 or go to the emergency room for trouble breathing, confusion, a seizure, chest pain, or fainting.
Call your care team the same day for repeated lows, high blood sugar that will not come down, vomiting that stops you from eating or drinking, moderate or high ketones, a bad headache with vision changes or swelling, or a change in how often your baby moves.
Before pregnancy: If you have diabetes and might become pregnant, book a preconception visit.
Frequently Asked Questions
Can you have a healthy pregnancy with diabetes?
Yes. MedlinePlus says that with good blood sugar control, most pregnancies have good outcomes. ADA and CDC both stress planning ahead, regular checks, and working closely with your care team. Risks are higher when blood sugar is high, especially in the first weeks.
Is pregnancy high risk if you have type 2 diabetes?
It often needs closer care. CDC says high blood sugar around conception raises the risk of birth defects, stillbirth, and preterm birth for people with type 1 or type 2 diabetes. That is why ADA recommends planning pregnancy and keeping blood sugar as close to normal as is safely possible. Your care team decides how often you are seen.
What A1C is safe for getting pregnant?
ADA says an A1C below 6.5% before pregnancy, if reached without too many lows, is linked to the lowest risk of birth defects, preeclampsia, and preterm birth. Your care team sets the goal that is safe for you. Ask for a preconception visit before you stop birth control.
Do you need insulin if you are pregnant with type 2 diabetes?
Many people do. ADA says insulin is the preferred medicine for diabetes in pregnancy and that metformin and glyburide should not be first-line medicines because both cross the placenta. NIDDK says insulin needs often rise as pregnancy goes on. Your prescriber decides your plan.
Can diabetes cause birth defects?
High blood sugar early in pregnancy can raise the risk. NIDDK says a baby's brain, heart, kidneys, and lungs start forming in the first 8 weeks. CDC says high blood sugar around conception raises the risk of birth defects for people with type 1 or type 2 diabetes. Planning ahead lowers this risk.
What is the difference between gestational diabetes and type 2 diabetes in pregnancy?
Type 2 diabetes was present before pregnancy, even if it was not yet diagnosed. Gestational diabetes starts or is first found during pregnancy, often around the 24th week, according to CDC. CDC says high blood sugar found early in pregnancy may mean type 1 or type 2 diabetes instead of gestational diabetes.
References
- Centers for Disease Control and Prevention. “Diabetes During Pregnancy.” Accessed October 2026.
- Centers for Disease Control and Prevention. “Gestational Diabetes.” Accessed October 2026.
- Centers for Disease Control and Prevention. “Gestational Diabetes and Postpartum Depression.” Accessed October 2026.
- American Diabetes Association Professional Practice Committee for Diabetes. “15. Management of Diabetes in Pregnancy: Standards of Care in Diabetes—2026.” Diabetes Care. 2026;49(Suppl. 1):S321–S338. Accessed October 2026.
- National Institute of Diabetes and Digestive and Kidney Diseases. “Pregnancy if You Have Diabetes.” Accessed October 2026.
- American College of Obstetricians and Gynecologists. “Gestational Diabetes.” Accessed October 2026.
- MedlinePlus, National Library of Medicine. “Gestational diabetes.” Review date May 29, 2026. Accessed October 2026.
- American Diabetes Association. “Gestational Diabetes.” Accessed October 2026.
Next Steps
If you have diabetes and might become pregnant, ask for a preconception visit and bring your latest A1C and full medicine list. If you are already pregnant, call your care team as soon as possible to plan your care.
For adults with type 2 diabetes or prediabetes who want lifestyle education alongside clinical care, the Done With Diabetes™ program, a type 2 diabetes protocol for everyday habits, organizes learning about meals, movement, sleep, and stress. It is not designed to manage diabetes in pregnancy. It does not diagnose or treat diabetes, set blood sugar targets, interpret test results, change medicines, or replace your prenatal or diabetes care team.