Abstract:
Estimation of the correct gestational age for fetuses is quite important in
distinguishing between the preterm and term infants in order to do the
necessary medical intervention after birth mainly for the preterm infants, in
which many parameters have been used to estimate the gestational age
including biparital diameter, femur length, head circumference, and
abdominal circumference.
The aim of the study was to predict fetal gestational age in the second and
third trimesters of pregnancy for a singleton gestation by using the fetal
transverse cerebellar diameter, in which its diameter in millimeters was
assumed to equal the fetal gestational age in weeks, and compare the
transverse cerebellar diameter with biparital diameter and the femur length
measurements used to estimate the gestational age for each fetus. A total of 50
gravid women at 15-38 weeks of gestation who attended for serial follow up
ultrasound scan at the ultrasound department in (Al-enqas Al-shahida Nada
medical center) were recruited in the study. Each pregnant woman had been
scanned once. the biparietal diameter, Femur length, and transverse cerebellar
diameter where obtained for each fetus and the data were analyzed by excel
and SPSS in reference to the expected gestational age calculated from the last
menstrual period for each woman.
The expected gestational ages of the singleton fetuses were between 15-38
weeks (mean 26.74), in which 10 cases were between 15-20 week GA, 21
cases between 21-30 week GA, and 19 case between 31-38 weeks GA, which
correspond to 20%, 42%, and 38% respectively.
The study showed strong correlation between the transverse cerebellar
diameter in millimeters and the expected gestational age in weeks in which the
correlation R= 0.921. The paired t-test for significance showed a significant
difference between the transverse cerebellar diameter in millimeters and the
corresponding expected gestational age in weeks at P = 0.05, but however it
showed no difference between 15-22 weeks of gestation which was statically
III
significant (P < 0.02) and R= 0.95 thus it can be used as a predictor for
estimating the gestational age during this period.
The study also showed a strong correlation between the estimated
gestational age by the biparietal diameter and the expected gestational age,
and between the femur length and the expected gestational age in which the
correlation was R=0.973 and R=0.975 respectively, paired t-test for
significance showed insignificant difference between the estimated gestational
age by biparietal diameter and Femur length and the corresponding expected
gestational at P = 0.05, thus, biparietal diameter and femur length can be used
with confidence in estimating gestational age during 15-38 weeks of
pregnancy.
