Estimation of mouse fetal weight by ultrasonography: application from clinic to laboratory.
Ultrasonographic assessment of fetal growth to estimate fetal weight has been widely used in clinical obstetrics but not in laboratory mice. Even though it is important to assess fetal growth abnormalities for gene-targeting studies using mice, there have been no reports of accurately estimated fetal weight using fetal biometric parameters in mice. The aim of this study was to establish an accurate mouse formula using fetal biometric parameters under ultrasound imaging. Using a high-frequency ultrasound system with a 40 MHz transducer, we measured 293 fetuses of biparietal diameter and mean abdominal diameter from day 12.5 postcoitus (p.c.) until day 18.5 p.c every day. Thirteen algorithms for humans based on head and/or abdominal measurements were assessed. We established an accurate formula based on measurement of the abdomen in Jcl:ICR mice to investigate gestational complications, such as intrauterine growth restriction.
Department of Obstetrics and Gynaecology, Osaka University Graduate School of Medicine, 2-2, Yamadaoka, Suita, Osaka 5650871,  Japan.
Thang M
TM
Nguyen
Hitomi
H
Nakamura
Atsuko
A
Wakabayashi
Takeshi
T
Kanagawa
Shinsuke
S
Koyama
Tateki
T
Tsutsui
Toshimitsu
T
Hamasaki
Tadashi
T
Kimura
D000005:Abdomen / Q000000981:diagnostic imaging*; D000465:Algorithms; D000818:Animals; D002508:Cephalometry / Q000662:veterinary*; D005260:Female; D020567:Fetal Weight; D006257:Head / Q000000981:diagnostic imaging*; D051379:Mice / Q000196:embryology*; D008813:Mice, Inbred ICR; D011247:Pregnancy; D012044:Regression Analysis; D013047:Specific Pathogen-Free Organisms; D016216:Ultrasonography, Prenatal / Q000295:instrumentation / Q000379:methods / Q000662:veterinary*