O30.0 - Twin pregnancy
O30.09 - Twin pregnancy, unable to determine number of placenta and number of amniotic sacs
O30.091 - Twin pregnancy, unable to determine number of placenta and number of amniotic sacs, first trimester
O30.092 - Twin pregnancy, unable to determine number of placenta and number of amniotic sacs, second trimester
O30.093 - Twin pregnancy, unable to determine number of placenta and number of amniotic sacs, third trimester
O30.099 - Twin pregnancy, unable to determine number of placenta and number of amniotic sacs, unspecified trimester