ICD-10-CM > O00-O9A > O30-O48 > O41 > O41.0 > O41.02 O41.02 Oligohydramnios, second trimester Non-Billable/Non-Specific Codes O41.02X0..., not applicable or unspecifiedO41.02X1..., fetus 1O41.02X2..., fetus 2O41.02X3..., fetus 3O41.02X4..., fetus 4O41.02X5..., fetus 5O41.02X9..., other fetus