The impact of switching to the one-step method for GDM diagnosis on the rates of postpartum screening attendance and glucose disorder in women with prior GDM. The San Carlos Gestational Study

Aims: To compare rates of FPG-HbA1C-based postpartum-glucose disorder (PGD) of women with prior gestational diabetes mellitus (GDM) by Carpenter-Coustan criteria (CCc) versus International Association of Diabetes and Pregnancy Study Groups criteria (IADPSGc).

Methods: 1620 women with GDM were divided into CCc group (2007-March 2012, n=915), and IADPSGc group (April 2012-2013, n=705). Pregravid (PG) body weight (BW) and body mass index (BMI) and postdelivery (PD) BW, BMI, waist circumference (WC), HOMA-insulin resistance (HOMA-IR), HbA1c, glucose and lipid profile were analysed. PGD definition: HbA1c ≥5.7% and/or FPG ≥5.6mmol/l.

Results: Postpartum screening attendance rates (PSAr) were similar in both groups, CCc: 791 (86.5%) and IADPSGc: 570 (81%) as in PGD rates (PGDr), CCc: 233 (29.5%) and IADPSGc: 184 (32.3%). Both cohorts had similar PG-BMI, WC and PD-BMI. Both CCc and IADPSGc women had a significantly higher probability of having PGD when PG-BMI ≥25Kg/m(2) (CCc: OR: 1.55; IC 95% 1.06-2.26; p=0.016), (IADPSGc: OR: 1.42; IC 95% 1.03-2.38; p=0.046) as well as when WC ≥89.5cm, and age ≥34years, and in CCc women when PD-WG >0Kg, all adjusted by ethnicity and parity.

Conclusions: Changing GDM diagnostic methodology did not affect PSAr and PGDr, in spite of screening more women. Thus, using IADPSGc allowed the identification of a larger number of women with PGD.