The PubMed search
identified 7,327 studies; 142 abstracts
reported a finding on the relationship
between maternal obesity and pregnancy
complications from a casecontrol
or cohort study, and the full text
of these articles were retrieved for detailed
examination. Of the retrieved articles,
40 studies mentioned GDM as an
outcome. Because only three casecontrol
studies (GDM case versus noGDM
control) were identified, we
excluded those studies and only included
those with a cohort design, leaving
a total of 37 studies from the
PubMed search to be screened for inclusion.
After reviewing the reference lists
of the 142 studies retrieved, we identi-
fied another 16 studies for possible inclusion.
Three additional studies were
identified from our examination of recent
review article reference lists. Of the
total 56 studies screened for final inclusion
in the meta-analysis, 36 studies were
excluded because the BMI or weight measure
did not reflect prepregnancy status
(n 12), there was no normal-weight
comparison group or overweight and
obese groups were combined (n 15), or
data were not presented in a way to allow
the construction of appropriate two-bytwo
tables (n 9).
A