In women with gestational diabetes mellitus factors influencing growth have a larger effect on placental weight than on birth weight.

BACKGROUND AND AIMS: Excessive fetal and placental growth are very common in diabetic pregnancy. We aimed to analyze in women with gestational diabetes mellitus (GDM) the association with birth weight (BW), placental weight (PW) and placental-to-birth weight (PWBW) ratio of acknowledged BW predictors. MATERIAL AND METHODS: We performed a retrospective analysis of a prospective cohort database from a tertiary hospital. Inclusion criteria were singleton pregnancy, diagnosis of GDM, delivery between 1982 and 2011 and gestational age at birth ≥23 weeks. Multiple regression analysis was performed using as dependent variables BW, PW and PWBW ratio and as independent ones maternal characteristics at baseline, metabolic characteristics (GDM diagnosis, treatment, control), pregnancy-induced hypertension, gestational age at delivery and fetal sex. Two sensitivity analyses were performed. RESULTS: We evaluated 2547 women, PW being available in 85.3%. BW was 3260g (2976, 3575), PW 620g (540, 720) and PWBW ratio 19.27 (17.20, 21.47). Among the 24 analyzed variables, there was an important overlap among those associated with BW, PW and PWBW ratio. For most characteristics associated with both BW and PW, the magnitude of the association was greater for the latter, both when promoting growth (i.e. prepregnancy body mass index, 3h plasma glucose at diagnosis) and when restricting it (insulin treatment). CONCLUSION: We conclude that in women with GDM and singleton pregnancies, variables associated with BW, PW and PWBW ratio overlap. The latter is the result of disproportionate associations with BW and PW, usually larger with PW.

Gestational diabetes mellitus in women with multiple pregnancies: is the metabolic abnormality milder?

OBJECTIVE: We aimed to compare maternal characteristics and dysglycemia after delivery in women with gestational diabetes mellitus (GDM) according to pregnancy being multiple (MP) or singleton (SP). The hypothesis was that women with GDM and MP would have a milder glycemic abnormality before and after pregnancy than those with SP. METHODS: We performed a cohort study of 2908 women giving birth between 1986 and 2009. Logistic regression was performed to discriminate between MP and SP after anamnestic pre-pregnancy characteristics. Kaplan-Meier and Cox regression analyses were performed to assess if MP was independently associated with both impaired fasting glucose (IFG)/impaired glucose tolerance (IGT) and diabetes after delivery. RESULTS: Family history of diabetes was the only independent anamnestic pre-pregnancy characteristic discriminating MP versus SP, OR 2.04 (95% CI 1.12, 3.70, p 0.019). The median time to progress to IFG/IGT was 7.52 years in SP (95% CI 6.92, 8.13) and 7.41 in MP (95% CI 3.84, 10.98), ns and the progression to DM did not differ. In addition, MP was not associated to IFG/IGT or to DM in the Cox regression analysis. CONCLUSIONS: In this cohort of women with GDM, those with MP did not demonstrate a lesser degree of dysglycemia after controlling for other pregnancy characteristics and pregnancy-independent factors.