Dr. Tiemeier have worked broadly in pediatric epidemiology for more than 20 years with an emphasis on child developmental research. At Harvard his research focusses on high-risk children, such as preterm children and homeless families. Together with colleagues and non-governmental agencies he has begun a cohort of women in Boston shelters and their children.

Dr. Tiemeier has published extensively on the etiology of child developmental problems with a particular focus on prenatal exposures. His other research interests include social and family environmental determinants of brain development, parental feeding and child eating behavior, and psychometric studies of child development, among others. He is a principal investigator of the Generation R Study, a large pre-birth cohort in Rotterdam, that enrolled nearly 10,000 mothers and their children. Ongoing research projects and interests focus on genetic and early life exposures; as his previous work showed that this shapes the vulnerability to neurodevelopmental problems. His ongoing studies include investigate how parenting and other environmental risk factors relate to brain development as assessed by braining imaging.