Diabetes during pregnancy can cause serious problems later – mothers need proper screening after birth

A growing number of women experience high blood sugar levels during pregnancy which typically resolve after birth.

Known as gestational diabetes, this is the most common metabolic disorder in pregnancy and affects one in seven women worldwide and one in sixteen in New Zealand.

Gestational diabetes is associated with complications during pregnancy. This includes high blood pressure, giving birth to a big baby (which increases the risk of vaginal birth complications) and increased rates of Caesarean section. It can also significantly affect the mother’s mental health and wellbeing.

Worryingly, more women are being diagnosed with gestational diabetes than ever before. Our new review of later health impacts for these women suggests they could be receiving better care after birth and in the long term.

Recommended care

Women who experienced gestational diabetes are ten times more likely to develop type 2 diabetes and twice as likely to experience cardiovascular disorders such as heart disease in the years following birth, compared to women who don’t develop gestational diabetes.

These mothers may also suffer from mental health problems, including depression, particularly in high-risk groups such as women of non-European ethnicity and those with a previous history of gestational diabetes.

For these reasons, care after birth for these women is important. This should include regular screening for blood sugar levels, cardiovascular problems and mental wellbeing after birth. It is also important women receive advice on diet and exercise.

Support for continued breastfeeding is also important as women who get gestational diabetes may experience a delay in milk flow and generally have lower breastfeeding rates compared to others. Breastfeeding may even reduce the risk of progression to type 2 diabetes.

Screening should continue for more than the first year after giving birth. Best practice would see women who had gestational diabetes being provided with long-term follow-up care, given their high risk for type 2 diabetes and heart problems.

Current evidence, however, suggests this isn’t necessarily happening. In a 2018 British study across several general practice centres, women who had gestational diabetes reported their levels of care during pregnancy dropped sharply after birth – to the point where they felt abandoned by the health system.

In a 2024 New Zealand study, mothers who had had gestational diabetes were interviewed five years after birth and expressed the need for more support from the health system.

While this study involved mothers’ perceptions about the optimal health and wellbeing for their children who were exposed to gestational diabetes, the findings also suggest room for improvement in care for the women themselves.

Gaps in clinical guidelines

Following on from this, our research team reviewed existing clinical practice guidelines to see if there were any gaps. These guidelines play an important role in contributing to quality care because they summarise research findings to provide recommendations for healthcare professionals to optimise health and reduce harm.

We looked at recommendations from 26 clinical practice guidelines published in the past decade in 22 countries, including New Zealand. The findings showed we could be doing better for women who have experienced gestational diabetes.

A key example relates to screening for diabetes after birth. It is common practice to check the blood sugar levels of women within three months of giving birth to see if they have gone back to normal.

This testing ensures any abnormalities (like high blood glucose, which may suggest diabetes) are detected so that appropriate management begins early on. Sadly, a nationwide study reported only about half of women receive this screening within six months after birth in New Zealand.

Sending reminders and combining these tests with other postnatal baby health checks and care procedures might encourage more women to check their blood sugar levels. However, very few guidelines we assessed recommend ways to raise the number of women who attend this screening.

Even fewer guidelines talk about screening for poor mental health, despite an increased chance these women could experience depression after birth.

Research we carried out in 2022, using randomised trial data of women with a previous history of gestational diabetes, revealed that around one in five self-reported symptoms of anxiety, depression or poor mental functioning at six months after birth.

Postnatal screening for mental health problems for all women who had gestational diabetes should be recommended to help improve quality of care.

Encouraging women who have had gestational diabetes to attend screening tests, continue breastfeeding and adopt healthy dietary choices and physical exercise requires health professionals to provide adequate counselling on the long-term risks of this condition. This will help women stick with their care plan after birth.