Introduction:
In addition to maternal hyperglycaemia, obesity and gestational weight gain, fasting hypertriglyceridemia has been identified as a risk factor for macrosomia in pregnancies complicated by gestational diabetes (1, 2). However, fasting lipids are not routinely measured in pregnancy (3). In the non-pregnant literature, postprandial hypertriglyceridaemia is recognized as a stronger predictor of atherosclerosis than fasting measures (4).
Aim:
To identify whether non-fasting lipids contribute independently to birthweight in offspring born to women diagnosed with gestational diabetes mellitus.
Methods:
We conducted a retrospective audit of 300 singleton pregnancies in women attending the gestational diabetes clinic at a regional tertiary hospital between January 2015 and December 2016. Singleton pregnancies were included if delivery was at term. At their initial diabetes education session, non-fasting serum was collected to measure total cholesterol (TC), low density lipoprotein cholesterol (LDLc), high-density lipoprotein cholesterol (HDLc), triglycerides (TG) and HbA1c. A chart audit examined their pregnancy and perinatal outcomes. Regression analysis models were used to evaluate the associations with infant birthweight.
Results:
Of the 300 mothers analysed, 243 (81%) were overweight/obese and 17 babies (6%) weighed >4000g. The mean values for BMI, gestational weight gain and birthweight were 31.9kg (95% CI 31.1-32.8), 6.2kg (95% CI 5.4 – 7.0) and 3332g (95% CI 3283 – 3380g) respectively. Overall, we found a significant association between non-fasting measures of TC (r = 0.12, p=0.016) and TG (r=0.158, p=0.003) with higher birthweight. We found no significant association between fasting glucose or post-load glucose levels, HbA1c or gestational weight gain and birthweight.
Conclusion: In this overweight cohort, we found significant associations between booking BMI, non-fasting TG and TC levels and birthweight, while there was no association for the glucose levels obtained on OGTT, HbA1c or gestational weight gain.