ICD-10-CM > O00-O9A > O30-O48 > O31 > O31.8 > O31.8X > O31.8X3 O31.8X3 Other complications specific to multiple gestation, third trimester Non-Billable/Non-Specific Codes O31.8X30..., not applicable or unspecifiedO31.8X31..., fetus 1O31.8X32..., fetus 2O31.8X33..., fetus 3O31.8X34..., fetus 4O31.8X35..., fetus 5O31.8X39..., other fetus