Highest mortality in pregnancy: (A) Fallot's tetrologv, (B) Coarctation of aorta, (C) Marfan’s syndrome, (D) Eisenmenger syndrome
Answer is D. Eisenmenger syndrome

These patients have pulmonary hypertension with shunt (right to left) through an open ductus or ASD or VSD.
Maternal mortality is high i.e. 50% & so is a perinatal loss (50%).
Fallot’s tetralogy, coarctaion of aorta & Marfan's syndrome hav mortality’ rate of 5-10%, 3-9% & 25% respectively