Unfortunately, ethanol and toxic alcohol metabolites like acetaldehyde also pass freely through the placenta, but the fetal liver doesn't have the necessary enzymes to metabolize them, so they build up inside the fetus really fast.

不幸的是，乙醇及有毒的酒精代谢产物，如乙醛，也可自由通过胎盘，而胎儿的肝脏却没有分解这些物质所必需的酶，因此它们可以在胎儿体内快速积聚。