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Meconium is the earliest stool of a mammalian infant. Unlike later feces, meconium is composed of materials ingested during the time the infant spends in the uterus: intestinal epithelial cells, lanugo, mucus, amniotic fluid, bile, and water. Meconium, unlike later feces, is viscous and sticky like tar, its color usually being a very dark olive green; it is almost odorless. When diluted in amniotic fluid, it may appear in various shades of green, brown, or yellow. It should be completely passed by the end of the first few days after birth, with the stools progressing toward yellow (digested milk). Meconium is normally retained in the infant's bowel until after birth, but sometimes it is expelled into the amniotic fluid (also called "amniotic liquor") prior to birth or during labor and delivery. The stained amniotic fluid (called "meconium liquor" or "meconium stained liquor") is recognised by medical staff as a sign of fetal distress, and puts the neonate at risk of meconium aspiration. Medical staff may aspirate the meconium from the nose and mouth of a newborn immediately after delivery in the event the baby shows signs of respiratory distress to decrease the risk of meconium aspiration syndrome. Meconium had been thought to be sterile until the team of researchers from the University of Valencia in Spain found bacterial communities in it so developed that they seemed to fall into two categories. Around half of the samples appeared to be dominated by bacteria that produce lactic acid, such as lactobacillus, while the other half mostly contained a family of so-called enteric bacteria, such as ''Escherichia coli''.〔JIMÉNEZ, Esther, et al. ''(Is meconium from healthy newborns actually sterile? )''; "()" Research in Microbiology. Vol. 159, Issue 3, pp. 187-193.〕 The Latin term ''meconium'' derives from the Greek , ''mēkōnion'', a diminutive of , ''mēkōn'', i.e. poppy, in reference either to its tarry appearance that may resemble some raw opium preparations, or to Aristotle's belief that it induces sleep in the fetus.〔(Health on the Net Foundation Mother and Child Glossary )〕〔.〕〔(【引用サイトリンク】url=http://www.etymonline.com/index.php?term=meconium&allowed_in_frame=0 )〕 A symptom of both Hirschsprung's disease and cystic fibrosis is the failure to pass meconium. Meconium can be tested for various drugs, to check for ''in utero'' exposure. Using meconium, a Canadian research group at the Hospital for Sick Children, University of Toronto, showed that by measuring a by-product of alcohol (FAEE) they could objectively detect babies exposed to excessive maternal drinking of alcohol in pregnancy.〔Chan D, Knie B, Boskovic R, Koren G. Placental handling of fatty acid ethyl esters: perfusion and subcellular studies. J Pharmacol ExpTher 2004; 310: 75-82.〕 In the USA, the results of meconium testing may be used by child protective services and other law enforcement agencies to determine the eligibility of the parents to keep the newborn.〔''G.B. v. Dearborn County Div. of Family and Children'', 754 N.E.2d 1027 (Ind.Ct.App., 2001).〕 ==Terminal meconium== Most of the time that the amniotic fluid is stained with meconium it will be homogeneously distributed throughout the fluid making it brown. This indicates that the fetus passed the meconium some time ago such that sufficient mixing occurred as to establish the homogeneous mixture. Terminal meconium occurs when the fetus passes the meconium a short enough time before birth/caesarean section that the amniotic fluid remains clear, but individual clumps of meconium are in the fluid. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Meconium」の詳細全文を読む スポンサード リンク
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