--- O30.121 Triplet pregnancy with two or more monoamniotic fetuses, first trimester

--- O30.122 Triplet pregnancy with two or more monoamniotic fetuses, second trimester

--- O30.123 Triplet pregnancy with two or more monoamniotic fetuses, third trimester

--- O30.129 Triplet pregnancy with two or more monoamniotic fetuses, unspecified trimester