Fetal Kidney Length for Determining Gestational Age in Third Trimester

  • Dr. Susheela Gayam DNB, DGO, HOD, Department of Obstetrics and Gynaecology, Vijay Marie Hospital & Educational Society, Khairatabad, Hyderabad, Telangana, India
  • Dr. Geethavani Bai DGO, Department of Obstetrics and Gynaecology, Vijay Marie Hospital & Educational Society, Khairatabad, Hyderabad, Telangana, India
  • Dr. Sashikala Paul MD, Department of Obstetrics and Gynaecology, Vijay Marie Hospital & Educational Society, Khairatabad, Hyderabad, Telangana, India
Keywords: Mean Kidney Length, Accurate Gestational age, Third Trimester, Biparietal diameter, Head Circumference, Abdominal Circumference, Femoral Length


Introduction: Accurate gestational age assessment is important in obstetric care. Ultrasonography plays a significant role in determination of Gestational Age. The ultrasonographic parameters used for GA determination are Crown rump Length, Biparietal diameter, Head circumference, and abdominal circumference and Femur length. Fetal kidney length (FKL) is one of the emerging parameter in estimation of gestational age. Renal length in mm is identified to approximate the gestational age in weeks. The present study is aimed to corroborate that FKL as a good parameter for gestational age estimation in third trimester.

Objective: Is to ascertain the precision of the ultrasonographic 'foetal kidney length' measurement as a reliable parameter for determination of GA in third trimester.

Material and Methods: One year Cross-Sectional and an Observational Study was conducted on 171 antenatal women in the third trimester after corroborating the gestational age by first trimester ultra sound and GA by LMP. Ultrasound measurements of Foetal kidney length were taken and correlation with last menstrual period gestational age and with other parameters (BPD, HC, AC, FL) were evaluated.

Results: This study showed a good correlation of Mean kidney length with GA by LMP of (r=0.991) than the rest of the parameters, HC(r=0.836), FL(r=0.853), AC(r=0.853), BPD (r=0.734) with p value=0.000 for all the parameters.

Conclusion: This study confirms that the fetal kidney length measurement is a reliable ultrasonographic parameter for estimating the gestational age accurately in the 3rd trimester and also it is observed that the correlation is increased when used along with other parameters.


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Fetal Kidney Length for Determining Gestational Age in Third Trimester
DOI: 10.17511/joog.2018.i03.02
Published: 2018-09-30
How to Cite
Gayam, S., Bai, G., & Paul, S. (2018). Fetal Kidney Length for Determining Gestational Age in Third Trimester. Obs Gyne Review: Journal of Obstetric and Gynecology, 4(3), 49-54. https://doi.org/10.17511/joog.2018.i03.02
Original Article