Which condition is least commonly associated with a sacrococcygeal teratoma?

Sacrococcygeal teratoma (SCT) is a tumor that occurs at the base of the spine, and it is the most common tumor found in neonates. Various maternal and fetal complications can be associated with the presence of SCT.

Hydronephrosis is often related to the structural effects of SCT, potentially causing urinary obstruction due to mass effect, making it a more common association. Likewise, polyhydramnios is frequently seen because the teratoma may contribute to increased fetal urination or result from fetal swallowing difficulties; thus, it is also a pertinent association.

Non-immune hydrops is a serious condition characterized by the accumulation of fluid in the fetal compartments, and in cases of SCT, it can occur due to the vascular supply and possible heart failure from high-output circulation caused by the tumor. Anemia from bleeding can arise as a complication due to the vascular nature of these tumors, risking hemorrhage.

In contrast, while hydronephrosis, polyhydramnios, non-immune hydrops, and anemia can all be linked to SCT, hydronephrosis tends to be the least commonly documented association among these options. This is because while SCT can lead to a variety of complications, the direct impact on renal