Acceleration of the newborn infant
Feldmann, H.U.; Rupek, R.; Tenhaeff, D.
Münchener Medizinische Wochenschrift 114(49): 2134-2137
1972
ISSN/ISBN: 0341-3098 PMID: 4678675 Document Number: 50749
A comparison is given of the distribution of birthweights in the time intervals 1913-34 and 1958-71. Only first births to mothers between 18 and 25 years of age were included, 1484 in the first and 5967 in the second interval. Percentages in the groups of infants less than 2500 g and by 500-g stages to 4500 g and more, were: in the earlier records 13.2, 20.9, 39.8, 21.2, 4.6 and 0.3; in the later 6.1, 14.9, 40.8, 29.8, 7.7 and 0.7. Percentages over 3000 g were 65.9 and 79.0. There was a parallel change in length: length up to 52 cm, 71.1 and 64.3; length 53 cm and over, 28.9 and 35.7%. There was no difference in head circumference. In the same periods mean weight of mothers, 6 to 10 days after delivery, was 59.3 kg in 1913-34 and 62.4 kg in 1958-71. Mean external conjugate measurements were 19.2 and 20.8 cm, and the percentage distribution of the measurements was: less than 20 cm 81.9 and 50.3; 21 cm and over 18.1 and 49.7. A radiography study showed the true conjugate to have increased by 1.5 cm. Mean ages of primiparae were 27.8 and 25.2 years and the number of first births to mothers less than 20 years of age had almost doubled in the interval. The incidence of breech presentation in single births rose from 3.1 to 4.0%. The difference was related, not to weight, but to age of mother. Caesarean section as a precaution in such young mothers with breech presentation at term showed the same pelvic measurements and birthweights as for mothers with vertex presentation. The acceleration of growth of women during the past half century, due to improvement of diet and environment, has now been passed on to the infant, with increase of birthweight and length.