Which condition is characterized by profound asymmetric fetal growth restriction and relative macrocephaly?

Digynic triploidy is indeed characterized by profound asymmetric fetal growth restriction with a relative macrocephaly. This condition arises from the fertilization of an egg by two sperm cells leading to an extra set of chromosomes, predominantly derived from the mother’s contribution.

In digynic triploidy, where there is likely double the maternal genetic material, the fetus often displays significant growth discrepancies. As the body size does not grow proportionately, the head may appear larger relative to the body due to the disproportionate growth dynamics, hence the term macrocephaly. This scenario is typical for digynic triploidy, whereas diandric triploidy often presents with a different growth pattern and associated anomalies.

Understanding the distinctions in growth patterns among various genetic conditions can help clinicians identify the underlying etiology of fetal growth restriction and tailor their management accordingly. Other syndromes listed do not share the same characteristic pattern of asymmetric growth and macrocephaly, making digynic triploidy the most fitting answer in this context.