1. Naeslund and Nylin;Hedenstedt; Naeslund,1946
2. the maternal circulation seem to show a survival time that is in accordance with the normal life span of RBC,1964
3. In complicated pregnancies, eg, toxaemia, vaginal bleeding, etc, the proportion of fetal red cells in the maternal blood is considerably higher than in uncomplicated ones;(Wimhofer et al, 1962; Bartsch,,1972
4. The maternal red cells have been reported to disappear rapidly from the blood of the infant. With agglutination tests, Eimer and Weiland (1969) failed to detect maternal RBC in the blood of newborns 40 hours after delivery,1967
5. Fetus to mother. After 10 years of intensive research the question of fetal erythrocytes in the maternal blood is fairly well documented, while the question whether fetal leucocytes are present in the maternal circulation is still somewhat controversial,1972