Is there a human fetal gallbladder contractility during pregnancy?

The purpose of this study was to evaluate whether human fetal gallbladder contractility exists in the second half of pregnancy. Ultrasound examinations were performed on 54 normal pregnant women from 20 to 40 weeks of gestation. Fetal gallbladder volume was monitored every 30 min from 08:00 to 18:00 h in each patient. Maximum gallbladder volume was related linearly with gestational age between 20 and 32-35 weeks of gestation, after which a plateau was observed. Minimum gallbladder volume was unchanged throughout gestation. Functional capacity (maximum volume - minimum volume) of the fetal gallbladder increased linearly with advancing gestation until 32-35 weeks gestation, and thereafter was constant. Contractility rate [(maximum volume - minimum volume/maximum volume)x100] increased curvilinearly with advancing gestation (R(2) = 30.7%, P < 0.0001). The daily change in fetal gallbladder volume showed a typical sinusoidal pattern, and the contractility cycle of gallbladder volume was unchanged during pregnancy (3.1 +/- 0.6 h). These results suggest that there is an apparent gallbladder contractility in human fetuses in utero, and that maternal meals seem not to affect the volume of the fetal gallbladder. Further study is needed to clarify the physiological role of fetal gallbladder contractility during pregnancy.