Abstract
Existing data related to the probability of breech presentation suggest that the breech presentation is a consequence of mere filling of the intrauterine space, with the same probability of breech and cephalic presentation. As a consequence, group of cephalic presenting fetuses is heterogenous. Some fetuses randomly assume the cephalic presentation while others assume cephalic presentation ‘intentionally’ for a reason. Before comparing breech and cephalic presenting fetuses/newborns, bias should be eliminated by subtracting from the cephalic-presenting group the number of fetuses/newborns that is identical with the number of breech-presenting fetuses/newborns with identical characteristics. The subtracted group should be added to the breech-presenting group before comparison with the remaining cephalic-presenting fetuses/newborns. The comparison should be corrected for the gestational age and according to data that are not influenced by delivery. Data suggest that the physiological process that accounts for 92% of cephalic-presenting human fetuses at delivery should be sought from the 25th gestational week onwards.
Acknowledgement
This study was supported by the Serbian Ministry of Science and Environmental Protection Grant Number 143021/2006.