Transplacental Transfer of Macromolecules: Proving the Efficiency of Placental Transfer of Maternal Measles Antibodies in Mother: Infant Pairs

BACKGROUND: Smaller substances <600 Daltons (Da) can transit human placenta while larger ones >1000 Da may not. This may not be consistent because maternal measles antibodies (MMA) are large immunoglobulin G molecules with molecular weight of 150,000 Da, could cross the placenta in mother-infant pairs. AIM: The objective was to assess the efficiency of placental transfer of MMA in mother-infant pairs at birth. SUBJECTS AND METHODS: Sera collected from mother-infant pairs were analyzed for MMA using enzyme-linked immunosorbent assay. Gestational age (GA) of newborns was determined using the last menstrual period, ultrasound scan, and the Dubowitz criteria, whereas their birth weight (BW) was measured using the bassinet weighing scale. RESULTS: Correlation coefficient (r) of MMA of mother-infant pairs at birth was significant (P < 0.01) and comparison of mean MMA for term and postterm deliveries were significant (P = 0.001) and (P = 0.007) respectively. Goodman and Kruskal's Gamma rank correlation of GA and BW was also significant (P< 0.001). CONCLUSION: Passage of MMA across placenta was efficient and newborn infants are protected from measles at birth.