Introduction

The role of sonography in the evaluation of morphology and detection of placental abnormalities in clinical conditions such as non-immune hydrops, gestational diabetes, chorioangioma, intraplacental hemorrhage and intrauterine growth restriction has been well established.

Placenta is primarily a fetal organ and its size is a reflection of the health and size of the fetus. One additional ultrasonographic parameter frequently used to assess the placenta is placental size. ^[1]

The measurement of placental thickness is relatively simple and clinically useful. Abnormal thickness of placenta is well recognized as a diagnostic harbinger in a wide spectrum of pathologic events. Placental thickness can contribute to the management of fetus at risk.^[2] Virtually, all the important clinical decisions, which include caesarean section, elective labour induction, etc., depend on the knowledge of the gestational age and placental position.

The role of placental thickness as a new parameter for estimating gestational age and placental thickness normograms in relation to gestational age have been published. Placental thickness measurement can differentiate normal from abnormal pregnancy.^[3]

Ultrasonography (USG) is commonly used to estimate the gestational age by measuring the fetal dimensions like the Biparietal Diameter (BPD), the Abdominal Circumference (AC), the Head Circumference (HC) and the Femur Length (FL).

There are some drawbacks in those above said parameters in estimating the gestational age. So, there is a need of another parameter for supplementing the gestational age estimation with minimal error. Nyberg and Finberg reported that the placental thickness parallels the gestational age ^[4].

In our present study we have tried to measure placental thickness at the level of umbilical cord and determine its relationship with gestational age of fetus in normal singleton pregnancy.

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Dr Himanshu Kumar Jaiswal

Junior Resident, Department of Radiology, Katihar Medical College