In many anatomy texts, it is often claimed and/or assumed that the cervical lordosis is a secondary curve and is not present during intra-uterine life. However, as early as 1977, Bagnall et al. demonstrated that the cervical lordotic curve is form in intrauterine life (9.5 weeks). In 195 fetuses, Bagnall et al. found that by 9.5 weeks, 83 % of fetuses have a cervical lordosis, 11% have a military configuration, and only 6% of fetuses are in the typically described kyphotic position of the cervical spine. This means that by 9.5 weeks, 94% of the fetuses are starting to use their posterior cervical muscles to pull the cervical curve away from the fetal “C” shape. In fact, the respiratory centers and the vertebral body ossification centers do not develop until the cervical lodosis is formed in utero. Fetuses have a cervical lorosis before birth, however, the lordosis increases during post-natal life at ages 3 months – 9 months as the infant raises his/her head and begins to sit up.
Harrison, D.D., 1946 Harrison, S.O., 1953; Harrison, D.E., 1972. Structural Rehabilitation of the Cervical Spine/ D.D. Harrison, D.E. Harrison, J.W. Haas
Bagnall KM, Harris PF, Jones PRM. A radiographic study of the human fetal spine. J Anat 1977; 124:791-802.
Kure S. X-ray radiometric analysis of the cervical spine of the normal infants and children (in Japanese with English abstract). J Tokyo Med Collage 1972; 30; 453-470.