Gestational Diabetes: Managing Blood Sugar That Rises During Pregnancy

01

What Causes It

Gestational diabetes develops when pregnancy hormones, particularly from the placenta, make the body's cells more resistant to insulin than usual. Most pregnant bodies compensate by producing more insulin to keep up; gestational diabetes happens when that compensation isn't enough and blood sugar rises above the normal pregnancy range.

It typically appears in the second half of pregnancy, which is why routine screening happens around 24 to 28 weeks. Risk is higher with excess weight, a family history of diabetes, older maternal age, and a prior pregnancy affected by it, though it can develop without any of these factors present.

02

Screening and Diagnosis

Most pregnant people are screened with a glucose tolerance test: drinking a sugary solution and having blood sugar checked at set time points afterward. Some clinics use a one-step approach with a single test, others a two-step approach starting with a shorter screening test and confirming with a longer one if it's abnormal.

A diagnosis is based on blood sugar exceeding set thresholds at one or more of the checked time points — it doesn't require symptoms, which is exactly why the screening test matters, since gestational diabetes usually causes no noticeable symptoms on its own.

03

Why Managing It Matters

Well-managed gestational diabetes has a good outlook for both mother and baby. Poorly controlled blood sugar, though, raises the risk of a larger-than-average baby, difficult delivery, low blood sugar in the newborn right after birth, and a higher chance of needing a cesarean delivery.

It also modestly raises the mother's risk of preeclampsia during that pregnancy and, longer term, the risk of developing type 2 diabetes later in life — which is why follow-up testing after delivery is part of standard care, not optional.

04

Managing Blood Sugar

The first line of management is dietary: consistent, moderate carbohydrate intake spread through the day, paired with regular physical activity as tolerated, and daily blood sugar checks at home with a glucose meter. Many people manage gestational diabetes with these changes alone.

When diet and activity aren't enough to keep blood sugar in range, medication — often insulin, and sometimes an oral medication depending on the situation — is added. Needing medication doesn't mean anything was done wrong; it simply means the body's needs during this pregnancy require more support than diet alone provides.

Anyone on insulin should know the signs of blood sugar dropping too low — shakiness, sweating, sudden hunger, or confusion — and treat it right away with a fast-acting sugar source like juice or glucose tablets, rechecking blood sugar shortly after. Readings that stay above target despite following the plan, or any noticeable decrease in the baby's movements, should be reported to the care team the same day rather than waiting for the next scheduled visit.

05

After the Baby Arrives

Gestational diabetes typically resolves after delivery, since it's driven by placental hormones that are no longer present. A glucose test around six to twelve weeks postpartum checks that blood sugar has returned to a normal range and screens for any underlying type 2 diabetes that gestational diabetes can sometimes unmask.

Because of the increased longer-term risk, ongoing periodic blood sugar screening — roughly every one to three years — is generally recommended even after a normal postpartum test, along with the same diet and activity habits that help prevent type 2 diabetes generally.