RESUMO
The placental thickness was estimated in about 608 normal antenatal women of all gestational ages [greater than 10 weeks] attending both Obstetrics and Radiology departments using the 3.5 Mhz USG probe. The placental measurement was taken at the insertion of the umbilical cord in all the cases. Mean placental thickness was calculated with standard deviation in all the cases. It was concluded, that the placental thickness gradually increased from 12 mm at 11 weeks to 40 mm in 39-40 weeks of gestation more or less corresponding to the gestational weeks. Between the 22nd and 40th weeks, it was corresponding to the period of gestation. In all these cases, other parameters were also taken. Thus the placental thickness can be used as an important parameter along with other parameters in early, mid and late mid trimesters where the exact duration of pregnancy is not known