الفهرس 
N ORMAL FETAL GROWTH AND WEIGHTOnly 14 pages are availabe for public view
 |  | from | 32 |  |  |
| | | from | 32 | | |
Abstract
I
n a previous relevant study a new formula was proposed, that incorporated placental thickness as an added parameter to the Hadlock’s 2 formula for estimation of fetal weight.
The aim of the present study is to verify the previously postulated formula that incorporates placental thickness in the estimation of fetal weight.
This validation study was conducted at Ain Shams University Maternity Hospital and included 600 pregnant women at a gestational age more than 36 weeks taking in consideration that the patient had accurate gestational dating for a singleton viable pregnancy and the actual birth weight at delivery is available and excluding multiple pregnancy, Intrauterine fetal death, Stillborn babies, known congenital fetal anomalies, placental anomalies, presence of uterine or adnexal gross pathology or markedly diminished liquor volume, (DVP <2 c.m).
All included women were subjected to 2D sonographic biometry for measuring the BPD, HC, FL and AC. In addition, the placental thickness was measured at the level of umbilical cord insertion in longitudinal direction twice in the same setting and average will be taken. All measurements had to be taken within 7 days of delivery. The estimated fetal weight will be calculated using Hadlock’s 2 formula as well as the new formula.
The current study results showed a significant positive correlation between placental thickness and actual birth weight (rs=0.413, p<0.001). The correlation coefficients for the EFW using the Hadlock’s 2 formula without and with adjustment to placental thickness were both high and significant [0.733 (p<0.001) and 0.749 (p<0.001), respectively]; with the latter being slightly higher than the former. The corresponding R2 were 0.567 and 0.598, respectively; which showed that adjustment of the Hadlock’s 2 formula to placental thickness raised the measure of goodness-of-fit by almost 3%.
The added predictability of adjusting the Hadlock’s 2 formula to placental thickness in prediction of both macrosomia and low birth weight was slight. The corresponding areas under the ROC curves were 0.935 vs. 0.929; and 0.931 vs. 915, respectively.
The results of the current study, therefore, showed a slightly better predictability of the Hadlock’s 2 formula when placental thickness was incorporated. This slightly better predictability was shown in general estimation of the birth weight, and in prediction of both macrosomia and low birth weight.