There is increasing evidence that in-utero exposure to hyperglycaemia and excess weight impacts adversely on offspring metabolic risk. As young onset type 2 diabetes (YT2DM) is more prevalent we compared the impact of YT2DM on pregnancy outcomes and neonatal body composition to type 1 diabetes (T1DM).
Clinical and PEAPOD body composition data were available from 27 T1DM (n=13) and YT2DM (n=14) pregnancies at RPAH. The majority of T1DM were Anglo-Celtic (62%), whereas 36% YT2DM were Asian, 29% Pacific Islander and 21% African. Maternal age was similar (34 yrs ± 5 YT2DM and 32± 4.7, T1DM). YT2DM was characterized by shorter duration of disease (2 yrs [0.8-2.9] vs 15[9-21]), higher pre-pregnancy BMI (28.9 vs 23.8 kg/m2), and lower folate supplementation (7.1% vs 69%), p≤0.001 for all. HbA1c pre-conceptually and by trimester were similar (YT2DM 7.01%, 6.93%, 5.98%, 5.87%,T1DM 7.03%, 6.88%, 6.29%, 6.0%) however YT2DM had significantly higher insulin requirements (136 vs 74units/day) and higher prevalence of excessive gestational weight gain (71% vs 54%). Despite these differences, higher birthweight (3.6kg vs 3.1kg p=0.03) and greater neonatal fat-free mass (3.0 vs 2.8kg p=0.04) were seen in T1DM. There were no differences in % fat or % fat free mass. Diabetes type was not independently associated with % fat on multivariate analysis. Notably, IUGR frequency was 28.6% vs 0% (p=0.1) for YT2DM vs T1DM. There were no differences between T1DM and T2DM in delivery gestation (36.9 vs 37.3 weeks p=0.6), preterm delivery (15.4 vs 14.3% p=1.0), pre-eclampsia (7.7% vs 7.1% p=1.0), or primary caesarean rate (33% vs. 56%).
Overall in YT2DM, in the context of comparable glycaemic control but higher pre-pregnancy weight and weight-gain, neonatal % body fat were not increased compared to T1DM and support the need for further study. The higher frequency of IUGR and low pre-conceptual folate use are concerning.