Solution: Fetal hydrops is a condition of excess fluid accumulation in the pleural, abdominal, and percardial spaces, as well as in the skin. It can be associated with a cystic hygroma, as in this case and there are at least 80 different causes. Over 50% of cases will not have an identifiable cause and there was no identified cause here, but some of the most common etiologies include: Cardiac defects, either structural or from arrhythmias; Turner syndrome; Trisomy 21, 18, 13; Immune hydrops (e.g. Rh incompatibility); and TORCH infections (toxoplasmosis, other infections, rubella, cytomegalovirus, herpes). Outcome is generally poor with a fetal mortality of around 70%. Obviously, the ultimate outcome often depends on the underlying cause.