Mean weight change was 56 g ( SD 47 , 95 % CI 50-63 ) for 197 babies in the introitus group compared with 53 g ( 45 , 46-59 ) for 194 babies in the abdomen group , supporting non-inferiority of the two approaches ( difference 3 g , 95 % CI -5.8 to 12.8 ; p = 0.45 ) .