Low values on 50 gram glucose challenge test or oral 100 gram glucose tolerance test are associated with good perinatal outcome

Abstract

We set out to reevaluate the hypothesis that high normal (negative) results of 50 g oral glucose challenge test or high normal glucose level on 100 g oral glucose tolerance test are associated with complications of pregnancy and delivery. This was a prospective study involving 735 nondiabetic women. The first group (n=352) was made up of pregnant women with normal 50 g oral glucose challenge test without previous history of diabetes mellitus or gestational diabetes. The second group (n=383) was made up of pregnant women without previous history of diabetes mellitus or gestational diabetes with an abnormal 50 g oral glucose challenge test and with normal 100 g oral glucose tolerance test and not more than one previous delivery. In nondiabetic women, we demonstrated a positive correlation between high normal 50 g glucose challenge test values and the incidence of preeclampsia, caesarean section rate, macrosomia, neonatal hyperlipidaemia and minor congenital abnormalities. We failed to confirm any relationship to any pregnancy complication in pregnant women with 2-hour glucose levels in the range 6.7-9.1 mmol/l on the 100 g oral glucose tolerance test. We have demonstrated a positive relationship between the incidence of premature rupture of membranes and 1-hour glucose level, caesarean section rate and maternal 1-hour glucose level or 1-hour glucose level minus fasting glucose level of 4.2 mmol/l, instrumental delivery rate and maternal 3-hour glucose level, incidence of neonatal macrosomia and 1-hour glucose level, and incidence of neonatal hyperlipidaemia and at least one high but normal glucose level on the 100 g oral glucose tolerance test. With regard to pregnancy and delivery complications there were no significant difference if the high normal value is on the 50 g glucose challenge test or on the 100 g oral glucose tolerance test. It is concluded that one high normal 100 g oral glucose tolerance test or high normal 50 g glucose challenge test are associated with adverse pregnancy and delivery outcome. Nondiabetic women with 50 g glucose challenge test value of 6.1 mmol/l and/or 100 g oral glucose tolerance test values of 5 mmol/l have a favourable pregnancy and delivery outcome.

Small-for-gestational age and its association with maternal blood glucose, body mass index and stature: a perinatal cohort study among Chinese women

“…Women whose BG level ≥7.8 mmol/L (140 mg/dL) at the GCT are more likely to have a larger baby at birth. 35 We excluded those women from this study to avoid the potential bias on the observed risk association of SGA with low BG. Maternal low BG levels suggest a low energy supply capacity that may cause problems for normal fetal growth.…”