Korean J Obstet Gynecol.  2003 Mar;46(3):537-541.

Normal Size of Fetal Kidneys: Sonographic Measurements

• Seo YS
• Choi CH
• Choi SJ
• Choi SJ
• Kim YA
• Yang SH
• Seo JM
• Park KH
• Kim JH

Abstract

OBJECTIVE
To establish size ranges of normal fetal kidneys by ultrasonogram during pregnancy.
METHODS
The A-P diameter and length of each of 450 kidneys in 225 consecutive fetuses between 19 and 41 weeks of gestation were measured on sonogram from March to August 2001 in Samsung Medical Center. Gestational ages were determined by last menstrual period and Crown-Rump Lengths of early stage of pregnancy. Abnormal fetuses, twins, offspring of diabetic mothers, and fetuses with renal pelvic dilatation of 5 mm or greater were excluded to avoid any questionable measurements.
RESULTS
The results showed normal distribution and results were similar to previous reports. There was a strong correlation between fetal renal size and gestational age, but no significant difference between right and left renal sizes in fetuses. Average A-P diameter and renal lengths were significantly different when compared across the range of gestational ages (p<.001).
CONCLUSION
As long as we know, this was the first report of size of the normal fetal kidney sonographically during pregnancy in Korea. We think that these results can be used to detect abnormality of fetal kidney and to estimate uncertain gestational age.

Keyword

Fetal kidney; Kidney length; Anterior to posterior diameter of kidney

MeSH Terms

Crown-Rump Length
Dilatation
Fetus
Gestational Age
Humans
Kidney*
Korea
Mothers
Pregnancy
Ultrasonography*