The number of women in England diagnosed with gestational diabetes has increased by 60% over a five-year period, a trend experts attribute to rising maternal age and obesity rates. In 2018, approximately one in 12 expectant mothers developed the condition, a figure that rose to one in eight by 2022.
Gestational diabetes occurs when a pregnant woman's blood sugar levels become too high, a condition that typically resolves after childbirth. It arises when the body cannot produce sufficient insulin to meet the increased demands of pregnancy. This complication can affect the placenta's function, potentially leading to a larger than average baby, breathing difficulties, and in rare instances, stillbirth. It can also elevate the mother's blood pressure to dangerous levels, increasing the risk of stroke and heart attack.
Obesity is identified as the primary risk factor, accounting for about half of all cases. This is linked to the impact of excess weight on insulin production and sensitivity, which also naturally declines with age. Data from the Office for National Statistics indicates a steady increase in the average age of mothers in recent decades.
These findings emerge as a separate study revealed a 70% surge in type 2 diabetes among women in their twenties in England over the past decade, with researchers citing increasing body mass index (BMI) as a contributing factor. Since 2011, the average BMI of women under 30 with diabetes has risen from 37.7 to 40.7, a level considered morbidly obese. Currently, about one in five pregnant women in the UK are classified as obese.
Gestational diabetes can also increase the risk of future health problems. Roughly half of women diagnosed with the condition go on to develop type 2 diabetes within five years. Research published in the journal BMJ Medicine, analyzing data from over 2.3 million mothers across 184 hospitals in England between 2018 and 2022, found that a gestational diabetes diagnosis was associated with a higher likelihood of premature birth. Premature birth, occurring before 37 weeks of pregnancy, can lead to severe infant complications, including underdeveloped lungs, brain bleeds, digestive issues, and long-term challenges such as vision or hearing impairment and developmental delays.
Screening for gestational diabetes typically involves an oral glucose tolerance test, usually administered between 24 and 28 weeks of gestation for women with specific risk factors. Symptoms such as increased thirst, frequent urination, tiredness, and thrush can often be mistaken for normal pregnancy changes, and in many cases, there are no clear warning signs.
Rebecca Reynolds, professor of metabolic medicine at the University of Edinburgh, described the rising diagnosis numbers as "concerning" and noted the impact on already strained maternity services. She emphasized the increased risk of future type 2 diabetes and cardiovascular disease for affected women, calling for improved preventative measures and postpartum support.
Dr. Sonya Babu-Narayan, clinical director at the British Heart Foundation, highlighted that these conditions elevate the risk of future heart attack or stroke. "Gestational diabetes often goes away after pregnancy, but it can increase women's risk of future cardiovascular disease," she stated. Healthcare professionals are advised to routinely inquire about pregnancy-related risk factors, such as diabetes or high blood pressure during pregnancy, even if the pregnancy occurred decades prior, as part of a comprehensive cardiovascular risk assessment.
While certain risk factors like age and ethnicity cannot be altered, lifestyle modifications can help manage blood sugar levels. Expectant mothers can reduce their risk by maintaining a healthy diet, staying physically active, and managing their weight before and during pregnancy.