Introduction: Exact determination of gestational age is crucial for appropriate antepartum care as well as successful outcome of deliveries. The exact knowledge of gestational age is also important for undertaking various diagnostic procedures that needs to be performed within a narrow range of a particular gestational age. While fetal biometry is one of the most common method of determination of gestational age and weight alternative methods such as measurement of placental thickness can also be used for determination of gestational age and other parameters in doubtful situations. We conducted this cross sectional study to find out whether placental thickness can be used for estimation of gestational age and other parameters.

Materials and Methods: This was a cross sectional study in which 403 pregnant women in their second and trimester were included on the basis of a predefined inclusion and exclusion criteria. Gestational age and other fetal parameters were determined on the basis of bio-physical parameters. The placental thickness was measured at the level of umbilical cord insertion and maximum thickness was determined in the cross section. Statistical analysis was done using SPSS software. P value less than 0.05 was taken as statistically significant.

Results: In this study of 403 women the mean age was found to be 28.36 +/- 7.6 years. In majority of the cases placenta was either anterior (42.4%) or posterior (30.5%). Placental thickness of 36.51 ±\ 4.67 was found to be corresponding to the gestational age of 37 weeks (Full-Term Gestation). The mean placental thickness was found to be having a linear relationship with gestational age and other fetal parameters and statistical association between placental thickness and gestational age as well as other fetal parameters was found to be significant.

Conclusion: Placental Thickness can be used for determination of gestational age and other fetal parameters in doubtful cases.

Keywords: Placental Thickness, Second and Third Trimester, Gestational Age, Biometry

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Dr Vandita Mor

Resident, Department of Radiodiagnosis, Geetanjali Medical College & Hospital (GMCH), Udaipur, India