Effect of an electronic reminder of follow-up screening after pregnancy complicated by gestational diabetes mellitus: a randomized controlled trial

Aim: To determine the effectiveness of despatching an electronic reminder of participation in screening for gestational diabetes. The reminder was sent to the women 1–8 years after delivery. Methods: A registry-based, randomized controlled trial in the North Denmark Region among women with gestational diabetes. Randomization was made, which included seven groups stratified by the child’s birth year (2012–2018). The intervention group received standard care supplemented by an electronic reminder through a secure nationwide email system (n = 731), while the control group received only standard care (n = 732). The primary outcome was based on blood testing for diabetes (OGTT, HbA1c or fasting P-glucose). Results: A total of 471 (32.1%) women participated in screening. The primary outcome was experienced by 257 women (35.1%) in the intervention group and 214 women (29.2%) in the control group. The effect of the reminder seemed to increase with recipient’s age, non-western origin, urban dwelling, and multiparity. Of those who participated in follow-up screening, 56 (3.8%) were diagnosed with type 2 diabetes. Conclusion: Electronic reminders, based on the principles of informed choice and patient-centred care, to women have been shown to support life-long participation in follow-up screening. Attempts to further stimulation of coverage could however be considered. Trail registration: ISRCTN registry (22/04/2022, ISRCTN23558707).