| Cause | Maternal laboratory evaluation |
|---|---|
| Antiphospholipid syndrome | • Lupus anticoagulant titers |
| • Anticardiolipin antibody titers | |
| • Anti-β2 glycoprotein I antibody titers | |
| Congenital syphilis | • Syphilis serologies |
| Fetomaternal hemorrhage | • Kleihauer-Betke test |
| Hemoglobinopathy | • Complete blood count |
| • Hemoglobin electrophoresis | |
| Poorly controlled/undiagnosed | |
| diabetes mellitus | • Fasting glucose level |
| • Hemoglobin A1c | |
| Red blood cell alloimmunization | • Antibody screen |
| Substance use | • Urine drug screen |
In select patients: thyroid disorder (thyroid function testing); other congenital infection (cytomegalovirus titer, toxoplasmosis titer, parvovirus B19 titer, Listeria culture).