ICD-10-CM > O00-O9A > O30-O48 > O41 > O41.0 > O41.01 O41.01 Oligohydramnios, first trimester Non-Billable/Non-Specific Codes O41.01X0..., not applicable or unspecifiedO41.01X1..., fetus 1O41.01X2..., fetus 2O41.01X3..., fetus 3O41.01X4..., fetus 4O41.01X5..., fetus 5O41.01X9..., other fetus