Earlier test for diabetes in pregnancy ‘beneficial for mothers and babies’

Women should be tested for gestational diabetes – a form of the condition that only develops during pregnancy – much earlier than the current standard, according to researchers.

Academics have called for a “major shift” in how gestational diabetes, which they describe as “a tremendous public health challenge”, is diagnosed and managed.

This includes a suggestion that testing should be done at 14 weeks of pregnancy rather than in the third trimester amid a global rise in obesity.

Gestational diabetes is the most common pregnancy complication, affecting thousands of women in the UK each year and an estimated one in seven pregnancies globally.

Also known as gestational diabetes mellitus (GDM), it happens when a hormone made by the placenta stops the body from using insulin effectively.

In England, women are screened for the condition if they have at least one or more risk factors, such as obesity or being aged over 40, between 24 and 28 weeks of pregnancy.

However, academics have suggested early diagnosis and treatment, especially before 14 weeks, could be “beneficial”.

It comes after studies found between 30% and 70% of women with gestational diabetes develop the condition before 20 weeks of pregnancy.

Treating the condition earlier could reduce the risk of some complications, researchers suggested.

A new Series paper, published in The Lancet, said: “As more women enter pregnancy with obesity and some degree of abnormal glucose or insulin regulation, gestational diabetes is becoming a more complex disease.”

Risks of gestational diabetes include premature birth, high blood pressure in pregnancy, babies growing larger than usual in the womb, and, in rare cases, stillbirth.

There can also be complications for newborn babies such as low blood sugar and an increased risk of breathing problems and obesity in later life.

Women who have had gestational diabetes are also more likely to have it in future pregnancies or go on to develop type 2 diabetes.

Co-author Dr Helena Backman, of Orebro University in Sweden, said: “The benefits of early GDM detection are clear – we can keep mothers and babies healthier during pregnancy and hopefully continue that path for a lifetime.

“What is needed now is earlier testing and an approach to managing GDM that takes the available resources, circumstances, and personal wishes of the patient into consideration.”

A diabetes blood test is carried out with a small device by a medic in gloved hands
Gestational diabetes occurs due to hormonal changes in the placenta (Hugo Philpott/PA)

In England, women deemed at risk of gestational diabetes are offered an oral glucose tolerance test, which involves a blood test on an empty stomach followed by a glucose drink, between 24 and 28 weeks of pregnancy.

After two hours of rest, a blood sample will be taken to see how the body has reacted to the glucose.

Women who have had gestational diabetes before will be screened earlier in subsequent pregnancies, usually after their booking appointment, which should take place with a midwife before 10 weeks.

If initial results are normal, they will be offered another test at 24 to 28 weeks.

Author Dr Yashdeep Gupta, of the All India Institute of Medical Science, described gestational diabetes as “a tremendous public health challenge”.

He said: “Women who experience it need support from the medical community, policymakers, and society as a whole to ensure they can effectively access proper treatment, reduce the stigma associated with GDM, and improve their overall pregnancy experience.”

Dr Lucy Chambers, head of research communications at Diabetes UK, said: “Gestational diabetes touches the lives of thousands of women in the UK each year, increasing the risk of poor health for them and their baby, not only during pregnancy but over their lifetimes too.

“This review showing that detection and treatment in the first trimester reduces some of these risks stresses the need for better understanding of how this evidence may impact on current antenatal care practices in the UK, where the standard is usually to test for gestational diabetes during the later stages of pregnancy.

“Investing into research to enable improved treatment and support for women with a gestational diabetes diagnosis is a priority too.”