Tianjin GDM Screening Project. Tianjin is the fourth
largest city in Northern China with over 13 million residents,
and 4.3 million residents live in six central urban districts.
All pregnant women who live in six urban districts have
participated in the universal screening for GDM since 1999
[9, 12, 13] by using the World Health Organization (WHO)
GDM criteria [14]. Following the WHO GDM screening
criteria, all pregnant women at 26–30 gestational weeks
participate in a 1-hour oral glucose tolerance test (OGTT)
with 50 g glucose load. Women who had a glucose reading
≥7.8mmol/L were invited to undergo a 2-hour OGTT with
a 75 g glucose load at the Tianjin Women’s and Children’s
HealthCenter.Allwomen confirming either diabetes (plasma
fasting glucose ≥7mmol/L or 2-hour glucose ≥11.1mmol/L)
or impaired glucose tolerance (IGT) (2-hour glucose ≥7.8
and