O31.8X - Other complications specific to multiple gestation O31.8 - Other complications specific to multiple gestation O31.8X - Other complications specific to multiple gestation O31.8X1 - Other complications specific to multiple gestation, first trimester O31.8X2 - Other complications specific to multiple gestation, second trimester O31.8X3 - Other complications specific to multiple gestation, third trimester O31.8X9 - Other complications specific to multiple gestation, unspecified trimester