Paediatricsmiddle twist
A term girl weighing 2.6 kg is examined before discharge. The backs of both hands and both feet are puffy and doughy, and there is loose redundant skin over the back of her neck. Her tone and suck are normal, the palate is intact, her fingers extend fully and each foot is normally shaped, with five digits on every limb. A soft systolic murmur is audible at the left sternal edge and the femoral pulses are distinctly weaker than the brachial pulses. Which one of the following best explains this combination of findings?