Fetal gall bladder development: A histo-morphometric study

Abstract

Background: The gall bladder development in fetal life is complex and starts as early as the 4th week of gestation; the abnormal development of the gall bladder is associated with various congenital abnormalities. The objective of the present study was to study fetal gall bladder development in relation to gestational age (GA) among fetuses. Methodology: In a cross-sectional observational study of 29 fetuses, the gall bladder parameters and histological changes are evaluated at different gestational age. The fetus was categorized based on GA into three categories of <20 weeks, 21–30 weeks, and 31 weeks and above. After dissection of the abdomen, the shape and location of the gall bladder were observed. The relationship of gall bladder with liver was observed. The gall bladder length (GBL) and gall bladder width (GBW) were measured. The histogenesis of the gall bladder was observed among all fetuses and developmental changes were noted. Results: The study included 29 fetuses, 14 males and 15 females. The first, second, and third groups comprised 5, 14, and 10 fetuses. The GA ranged from 13 to 35 weeks. The mean crown-rump length (CRL) of the fetuses was 19.34 ± 6.32 cm. The mean GBL was 2.06 ± 0.83 cm and the mean GBW was 0.77 ± 0.32 cm. The GBL and GBW increased with CRL, GA, and weight. The strong positive correlation was observed between GBL, GBW with GA and CRL. On microscopy, among the first group, fetal gall bladder at 13 weeks showed solid structure with obliterated lumen and area of early canalization. The muscular layer initially was very thin and comprised only few haphazardly arranged muscle fiber in the first group, the thickness was found to be more in the second group and a well-formed adult-like muscular layer was found in the third group. The loose connective tiisue, the outer most layer was pronounced in the third group. Conclusion: The fetal gall bladder parameters show linear increase with GA and CRL. The location, size, and relation of the fundus with margin of gall bladder in fetus undergo changes with the development of the fetus. The fetal gall bladder undergoes marked histological changes during development.