Objective: To examine glycaemic variability (GV) and glycaemic control (GC) parameters in early pregnancy with subsequent development of gestational diabetes mellitus (GDM). Design: Longitudinal observational study. Setting: Pregnant women from KK Women and Children’s Hospital in Singapore Participants: 51 study participants in the first trimester (9-13 weeks’ gestational), and 44 participants (18-23 weeks’ gestation) in the second trimester of pregnancy. Methods: Independent t-tests were used to examine the differences in the parameters between participants who developed GDM and those who did not. Main outcome measure: GDM was determined at 24-30 weeks’ gestation using oral glucose tolerance test (OGTT). GV parameters examined were, mean amplitude of glycaemic excursion (MAGE), standard deviation of blood glucose (SDBG) and mean of daily continuous 24 h blood glucose (MBG) and coefficient of variation (CV). GC parameters measured were, J-Index and % time spent in glucose target ranges. Results: In the second trimester of pregnancy, mean amplitude of glycaemic excursions (MAGE) was significantly higher in participants who subsequently developed GDM, compared to those who did not (mean (SD): 3.18(0.68) vs 2.60(0.53), p=0.02). Other study parameters measured in the second trimester of pregnancy were not significantly different between groups. There were no significant associations between all the GV and GC parameters determined from the CGM in the first trimester with subsequent development of GDM (p>0.05). Conclusion: MAGE is an important GV parameter associated to the development of subsequent GDM in pregnant women. The findings highlight the potential value of CGM in gestational glycaemic profiling.

Objective: To elucidate the correlation between sleep disturbances and blood pressure during pregnancy in women with no pre-existing hypertension. Design: Prospective cohort study. Setting: Outpatient specialist clinics at KK Women’s and Children’s Hospital, Singapore. Population: Women with viable singleton pregnancies confirmed by ultrasonography at less than 14 weeks of amenorrhea at first visit. Methods: 926 subjects were recruited for this study in the outpatient specialist clinics at KK Women’s and Children’s Hospital, Singapore, between September 1, 2010, and August 31, 2014. They were followed up throughout pregnancy with sleep quality, blood pressure and uterine artery doppler assessed at each visit. Main outcome measures: sleep quality, blood pressure and uterine artery doppler. Results: Sleep progressively worsened as pregnancy advances. Shorter sleep duration and poorer sleep efficiency were associated with higher blood pressure, especially in the first trimester. Mixed model analysis demonstrated overall positive correlation between sleep quality represented by Pittsburgh Sleep Quality Index (PSQI) score and diastolic blood pressure (DBP) (p<0.001) and mean arterial pressure (MAP) (p=0.005) during pregnancy after considering all trimesters. Sleep duration was found to be negatively correlated with both systolic blood pressure (SBP) (p=0.029) and DBP (p=0.002) while sleep efficiency is negatively correlated with DBP (p=0.002) only. Overall poor sleep during pregnancy was also found to be correlated to higher uterine artery pulsatility index. Conclusion: Our prospective study demonstrated that sleep quality is significantly correlated with blood pressure during pregnancy with most prominent effect in the first trimester.