ICD-10-CM > O00-O9A > O30-O48 > O36 > O36.8 > O36.81 > O36.813 O36.813 Decreased fetal movements, third trimester Non-Billable/Non-Specific Codes O36.8130..., not applicable or unspecifiedO36.8131..., fetus 1O36.8132..., fetus 2O36.8133..., fetus 3O36.8134..., fetus 4O36.8135..., fetus 5O36.8139..., other fetus