Table 1: Etiology of neonatal polycythemia [22].
| Erythrocyte transfusion (Passive) |
| Delayed clamping of umbilical cord |
| Uncontrolled or precipitous delivery |
| Intrapartum hypoxia |
| Twin-to-twin transfusion (In 10-15% of monochorionic twins) |
| Materno-fetal transfusion |
| Increased intrauterine erythropoesis (Active) |
| Plasental insufficiency Preeclampsia Other hypertensive disorders Other vascular problems |
| Maternal hypoxemia due to cardiac or pulmonary diseases Cardiac and pulmonary disorder Drugs (i.e. propranolol) Smoking High altitude Postmaturity |
| Diseases associated with fetus Large-for-gestational age newborns Maternal diabetes mellitus Beckwith-Wiedemann syndrome Endocrine disorders (Congenital adrenal hyperplasia, hypothyroidism, hyperthyroidism) Chromosomal disorders (Trisomi 21, 18, and 13) |