Clinical Assessment of Gestational Age in the Premature Infant

ABSTRACT

Recently the clinical estimation of gestational age has been of increasing concern particularly in premature babies because of its great aid in treament and expectation of future health. The clinical distinction between small-for-dates infants and premature babies offers great difficulty, but can be made readily if the gestational age is known. The author has investigated the clinical estimation of gestational age in 100 premature infants who were born at the Seoul National University Hospital, the Eul Ji Hospital and the So Wha Hospital from March to August in 1977, in order to evaluate the correlation between the gestationl age calculated from LMP and the clinically estimated gestaionl age using two charts designed by Brazie and Lubchenco, which were based on 16 physical criteria and 20 neurologic criteria with the following results. 1) The sex and age distribution of the 100 premature infants showed predominance in male and in the 34th336th weeks of gestional age. 2) The numbers of babies whose weight was appropriate, small and large for gestational age were 89, 9 and 2 respectively according to University of Colorado Medical Center Example, while they were 91, 4 and 5 according to the chart based on Rha's report in 1976 in Korea. 3) The correlation percentages between the gestational age determined by each of the 16 physical criteria and those calculated from LMP were as following; vernix (88%), skin and nail plates(88%), recoil-leg(75%), skin thickness appearance(73%), sole creases(68%), genitalia, testes and scrotum(67.5%) and so forth. 4) The correlation percentages between the gestational ages determined by each of the 20 neurologic criteria and those calculated from LMP were as following, pupillary reflex(94%), grasp reflex(90%), vertical positions(87%), head lag (83%), glabellar tap(81%), body extensors(80%), horizontal positions(80%), rooting reflex(80%), and so forth. 5) The correlation coefficiency between the clinically estimated gestational age using the above described two charts and that calculated from LMP was 0.98. And the regression formula for the latter (X) against the former (Y) was Y=0.786X+7.753. With the above results, the author could conclude that clinical estimation of the gestational age with the two charts of Brazie and Lubchenco was highly correlated and it deserves to be recommended for clinical purpose.