Aim: To describe the clinical presentation and the prognosis of autoimmune type 1 diabetes (T1D) that was first revealed during pregnancy masquerading as gestational diabetes mellitus (GDM).
Methods: We reviewed the files of 21 women in whom diabetes was revealed during a pregnancy ("index pregnancy") and progressed to T1D after delivery, and in whom GAD and/or IA-2 autoantibodies were found.
Results: The median age and BMI of the women were 31 years and 19.8 kg/m(2). Eleven women had at least one risk factor for GDM. Eight of the 12 multiparous women had had an abnormal outcome of previous pregnancy, including GDM in five. GDM was diagnosed at week 26 (range: 4-38) of gestation by screening in 18, because of macrosomia in two and during hyperglycaemic crises in three. All were treated with insulin, from the time of diabetes diagnosis in 10 and after 4 weeks (range: 2-15) in 11. Term of delivery was 38 (range: 26-41) weeks. Abnormal outcomes occured in 14 pregnancies, including two fetal deaths, four preterm deliveries and eight macrosomic infants. No congenital malformations were reported. After delivery, insulin therapy was stopped in 18 women for 6 months (range: 2-48). The diagnosis of the autoimmune origin of diabetes was established during the index pregnancy in only eight cases.
Conclusion: T1D may reveal as GDM in women with or without risk factors for GDM and is associated with a poor prognosis, partly because the correct diagnosis and treatment are delayed. Whether screening for autoimmune markers of T1D should be performed more systematically in women with GDM deserves to be studied.
Copyright © 2010. Published by Elsevier Masson SAS.