Meconium: It Can Cause a Sticky Mess

Discussion
During fetal life from approximately 12-13 weeks gestation, meconium accumulates in the small bowel and migrates to the large bowel and rectum by ~20 weeks gestation. Meconium is a combination of bile, mucous, desquamated intestinal cells, bowel secretions, dessicated swallowed amniotic fluid and lanugo. It is sterile before birth and once produced is odorless with a blackish green (sometimes brown or yellow) color, and tarry or sticky quality. Defecation does not occur during fetal life unless the fetus is significantly stressed. Normal meconium passage after birth occurs within 24-48 hours of life (more often within 24 hours). Delayed meconium passage begins an evaluation for anatomical obstruction (e.g. imperforate anus, colonic/rectal stenosis or atresia, mass effect, etc.), peristaltic problems (e.g. functional ileus, Hirschsprung disease) or intraluminal problems (e.g. cystic fibrosis) or other causes. Extreme prematurity also can have delayed passage of meconium as it is thought the normal intestinal musculature and/or innervation is also too immature to produce appropriate peristalsis and meconium movement. Imaging can be found here. Meconium’s tarry quality leads many parents commenting that they are happy once the stools transition and hygiene is easier to perform.
Learning Point
Meconium is normal and usually does not cause problems but they can be serious when they occur.
Meconium ileus is a neonatal intestinal obstruction problem caused by extre...

Source: PediatricEducation.org - February 13, 2023 Category: Pediatrics Authors: Pediatric Education Tags: Uncategorized Source Type: news