ICD-10-CM > O00-O9A > O30-O48 > O31 > O31.1 O31.1 Continuing pregnancy after spontaneous abortion of one fetus or more Non-Billable/Non-Specific Codes O31.10Continuing pregnancy after spontaneous abortion of one fetus or more, unspecified trimesterO31.10X0..., not applicable or unspecifiedO31.10X1..., fetus 1O31.10X2..., fetus 2O31.10X3..., fetus 3O31.10X4..., fetus 4O31.10X5..., fetus 5O31.10X9..., other fetusO31.11Continuing pregnancy after spontaneous abortion of one fetus or more, first trimesterO31.11X0..., not applicable or unspecifiedO31.11X1..., fetus 1O31.11X2..., fetus 2O31.11X3..., fetus 3O31.11X4..., fetus 4O31.11X5..., fetus 5O31.11X9..., other fetusO31.12Continuing pregnancy after spontaneous abortion of one fetus or more, second trimesterO31.12X0..., not applicable or unspecifiedO31.12X1..., fetus 1O31.12X2..., fetus 2O31.12X3..., fetus 3O31.12X4..., fetus 4O31.12X5..., fetus 5O31.12X9..., other fetusO31.13Continuing pregnancy after spontaneous abortion of one fetus or more, third trimesterO31.13X0..., not applicable or unspecifiedO31.13X1..., fetus 1O31.13X2..., fetus 2O31.13X3..., fetus 3O31.13X4..., fetus 4O31.13X5..., fetus 5O31.13X9..., other fetus