The COCOA study was initiated in 2007 and has enrolled around 3102 pregnant women. A distinctive feature of this study is that it evaluates a wide range of exposure factors, such as outdoor environmental exposure to PM2.5 and PM10 during pregnancy, indoor environmental exposure including mold, and maternal mental health, and also measures DNA and microbiome.

Between 2009 and 2011, GUSTO enrolled 1247 pregnant women, who gave birth to 1190 newborns. The ethnic composition of the participants was 58.5% Chinese, 25.5% Malay, and 16% Indian. S-PRESTO is a somewhat unusual cohort study that investigates the effects of pre-pregnancy lifestyles, enrolling 1039 women from 2015 to 2017 and tracking the nearly 373 children born.

JECS is a birth cohort study that was launched as a project of the Japanese Ministry of the Environment. It started enrolling pregnant women in 2011 for 3 years till it had registered 103,106 pregnant women cooperating with 15 regional centers from Hokkaido to Okinawa. They gave birth to 104,062 infants, who are being followed up. In particular, JECS focuses on investigating the effects of environmental chemicals including heavy metals on children's health.
The T-Child study is the oldest birth cohort study in the A2BC network. Between 2003 and 2005, it recruited 1701 pregnant women who planned to give birth at the National Center for Child Health and Development, and it has been tracking the 1550 babies they delivered.