sentence: For the combined xenoestrogenic activity , in the primary analysis ( Model 1 ) , IQR increases in XER activity in the PFAA serum fraction were associated with lower BW ( − 48g ; 95 % CI : − 90 , − 6 ) and shorter birth length ( − 0.3cm ; 95 % CI : − 0.5 , − 0.1 ) .