00461nas a2200169   4500000000100000008004100001100001400042700001200056700001200068700001300080700001300093700001200106700001300118700002000131700001300151245012700164       2018                            d1 aKennedy S1 aDwyer T1 aHirst J1 aVillar J1 aKnight H1 aOhuma E1 aHennig B1 aPapageorghiou A1 aCheikh I00aSocial gradient of birthweight in England assessed using the INTERGROWTH-21<sup>st</sup> gestational age-specific standard