The Effects of Hyperemesis Gravidarum on the Oral Glucose Tolerance Test Values and Gestational Diabetes

This study is aimed at determination whether pregnant women who develop hyperemesis gravidarum in the first trimester have a tendency to develop gestational diabetes mellitus (GDM). It is also aimed at identification of effects of hyperemesis gravidarum and GDM on prenatal and neonatal status in case they were detected together. Hyperemesis gravidarum diagnose was based on the following signs and symptoms. To diagnose GDM, first trimester fasting blood glucose measurement and subsequent blood glucose monitoring and 75-g oral glucose tolerance test (OGTT) were performed in the second trimester. A total of 949 singleton pregnant women (95 with and 852 without hyperemesis gravidarum) who met our criteria were included in the study. In the first trimester, plasma blood glucose and positive GDM screening were found to be significantly higher in the hyperemesis gravidarum group compared to the control group (p=0.042 and p<0.001, respectively). However, actual GDM cases were similar between both groups. The positive predictive value was significantly lower in the hyperemesis gravidarum group (28.5% vs. 72.7%, p=0.003). In the second trimester, the prevalence of GDM was 6.6% in the hyperemesis gravidarum group and 7.3% in the control group, with no significant difference (p=0.218) between-groups. In this study, hyperemesis gravidarum was found to cause changes in maternal metabolism in the first trimester of pregnancy due to limited calorie intake and fasting; in the presence of hyperemesis gravidarum, it should be known that the positive predictive value of first trimester gestational diabetes screening may decrease and the diagnosis of pseudo-GDM may increase.