Monogenic diabetes caused by GCK gene mutation is misdiagnosed as gestational diabetes - A multicenter study in Portugal.

AIMS: Monogenic diabetes is an underdiagnosed type of diabetes mellitus, which can be harmful in pregnancy. We aim to estimate the prevalence of diabetes caused by the mutation of the glucokinase gene (GCK-MODY) in pregnant women diagnosed with gestational diabetes mellitus (GDM) and to characterize pregnant women with this suspicion. METHODS: A multicenter observational study with data prospectively collected from pregnancies with GDM was conducted. Two groups of pregnant women were considered: those with GCK-MODY criteria and those without those criteria. RESULTS: Of 18421 women with GDM, 3.6% (n = 730) had the GCK-MODY clinical criteria. A prevalence of 1.5% of GCK-MODY is estimated in women with GDM in Portugal, which is higher than in Northern European countries. Suspected GCK-MODY women had statistically higher odds of having neonates below the 25th percentile (OR = 1.23, 95%CI = 1.04-1.46, p = 0.016) and having prediabetes and diabetes in postpartum reclassification (OR = 2.11, 95%CI = 1.55-2.82, p < 0.001 and OR = 5.96, 95%CI = 3.38-10.06, p < 0.001, respectively). CONCLUSIONS: Higher odds of neonates below the 25th percentile was probably due to excessive insulin treatment in cases where both the mother and the fetus have the mutation. It is essential to consider the diagnosis of GCK-MODY in all women with GDM criteria for better management of diabetes in pregnancy.

Benefit of insufficient gestational weight gain in obese women with gestational diabetes mellitus: A multicenter study in Portugal.

BACKGROUND: Both obesity and gestational diabetes mellitus (GDM) are independent risk factors for adverse maternal and fetal outcomes. The Institute of Medicine (IOM) recommends different targets for an adequate gestational weight gain (GWG), depending on the prepregnancy body mass index, but they have been questioned. We aim to compare obese pregnant women with GDM according to GWG stratification (insufficient, adequate and excessive) with regard to maternal and neonatal outcomes and to clarify whether insufficient GWG can be associated with better outcomes. METHODS: A multicenter observational study with prospectively collected data of obese singleton pregnant women with GDM was conducted. GWG was expressed according to the 2009 IOM's recommendations. RESULTS: Of 4563 obese women with GDM, 34.5%, 30.4% and 35.2% registered insufficient, adequate and excessive GWG, respectively. Multiple logistic regression analysis revealed that women with insufficient GWG had lower odds of gestational hypertension, preeclampsia, caesarean section, large for gestational age (LGA) neonates and prediabetes in postpartum. Despite the higher incidence of small for gestational age (SGA) neonates, they were not associated with adverse outcomes. Women with excessive GWG had higher odds of caesarean section, macrosomic and LGA neonates. CONCLUSIONS: Insufficient GWG in obese women with GDM was beneficial due to better maternal and neonatal outcomes. In clinical practice, we should be strict with regard to weight gain in obese pregnant women with GDM and encourage a reduced GWG, provided an adequate fetal growth is guaranteed.