Some studies differed in cut off points such as 31, 32 and 34 cm(5,6,9) which may due to the different population. Prediction for high birthweight was SFH of 38 cm. with the sensitivity and specificity of 97.37% and 96.42%, respectively(3)Other studies used the value132 Thai J Obstet Gynaecolof 39 and 40 cm(6,9) This difference may also due to difference in population, number of samples and duration of data collection. From this study, mothers with SFH of higher than or equal to 38 cm had increased
risk of cesarean delivery and shoulder dystocia.
This means that doctors should be aware of this complication
and notify the referral center.