Diabetes and pregnancy

Monica Therese Cating-Cabral, MD·28 March 2025, 10:41 pm

As an endocrinologist, I see many women with type 1 diabetes, those who always need insulin injections, or type 2 diabetes, those who have insulin resistance who can be treated with both tablets and insulin. For these women to have successful pregnancies, it is important that their diabetes is controlled well before they even conceive to avoid possible congenital anomalies. Certain tablets and kinds of insulin should also be avoided, and you should be seen frequently by your doctor during pregnancy to maintain healthy blood glucose levels.

There are also women who do not have either type of diabetes, but are found to have gestational diabetes mellitus (GDM), a kind of diabetes that first appears during pregnancy and usually resolves after the baby is born. It can be a confusing and sometimes frightening diagnosis, but with the right information and care, both mother and baby can remain healthy.

Gestational diabetes usually occurs in the second or third trimester and affects how your body uses glucose, the main source of energy. Normally, your body makes enough insulin during to handle glucose that comes from the food we eat. Insulin is a hormone that helps move glucose from the blood into your cells for energy. But for some women, the body can’t make enough insulin or can’t use it effectively during pregnancy. As a result, blood glucose levels rise, leading to GDM.

There are women who do not have either type of diabetes, but are found to have gestational diabetes mellitus, a kind of diabetes that first appears during pregnancy and usually resolves after the baby is born.
PHOTOGRAPH COURTESY OF JOHN HOPKINS MEDICINE

Any pregnant woman can develop GDM, but certain factors increase the risk:

•Being overweight or obese before pregnancy

•Family history of diabetes

•Being older than 25 years during pregnancy

•Having had gestational diabetes in a previous pregnancy

•Belonging to certain ethnic groups, such as Asian, Hispanic, African-American or native American

•Having polycystic ovary syndrome (PCOS)

•Having a previous baby weighing more than eight pounds

Filipino women are at increased risk for GDM and testing is usually recommended during the first prenatal visit using an oral glucose tolerance test (OGTT) where blood samples are drawn before and after drinking 75 grams of glucose (usually orange-flavored). The reference values used are different from those used to diagnose type 2 diabetes and only one value has to be abnormal to make the diagnosis of GDM. If this test is normal, your doctor can test again between the 24th and 28th week of pregnancy if GDM is suspected.

While having GDM doesn’t mean you had diabetes before or that you’ll have it after, it does need to be managed carefully. If left untreated, high blood glucose can cause complications for both mother and baby.

For the mother:

•Higher risk of high blood pressure or preeclampsia

•Greater chance of needing a C-section

•Higher risk of developing type 2 diabetes in the future

The good news is that GDM can usually be managed with lifestyle changes and close monitoring.

1. Healthy eating: A diet rich in whole grains, lean protein, vegetables, fruits and healthy fats can help keep blood glucose stable. Avoiding sugary snacks, sweetened drinks and processed foods is key.

2. Regular exercise: Physical activity helps the body use insulin better. Walking, swimming, or prenatal yoga can be good choices - but always check with your doctor before starting or continuing an exercise program.

3. Monitoring blood glucose levels: Your blood glucose levels will need to be checked several times a day using a small finger prick and glucose monitor, or using a continuous glucose monitor inserted behind the arm. This helps guide your care and ensures your levels stay within the target range.

4. Medication, if needed: If diet and exercise aren’t enough to control blood glucose levels, your doctor may prescribe insulin or oral medications that are safe in pregnancy.

In most cases, GDM goes away after childbirth. However, it is important to follow up with your doctor. About 50 percent of women with GDM develop type 2 diabetes later in life. Remember to do another OGTT about six weeks after delivery to confirm that glucose levels have returned to normal, then yearly for the next few years to detect pre-diabetes or diabetes so it can be managed right away.

Breastfeeding is encouraged, as it can help lower the baby’s risk of developing obesity and diabetes and may also help the mother lose pregnancy weight.

Gestational diabetes may sound alarming, but with early detection, proper management and support, most women go on to have healthy pregnancies and healthy babies. If you’re pregnant or planning to become pregnant, talk to your healthcare provider about your risk and how to reduce it. Awareness, healthy habits and regular checkups are your best tools in keeping both you and your baby safe.

Daily Tribune

Diabetes and pregnancy

For the baby:

For the mother: