Q. A 10-day-old male neonate is admitted to the neonatal intensive care unit due to respiratory distress. He was born at 36 weeks gestation to a 19-year-old mother. The mother has not received any prenatal care. Upon examination, he has normally functioning ala nasi (nostril wings) with a respiratory rate of 63/minute. Fundus examination cannot be done due to lens opacity. No conjunctival discharge is noted. Skin examination shows multiple purply pigmented skin lesions. A continuous "machinery-like" murmur is auscultated over the left infraclavicular region. Based on the above clinical examination, the neonate's mother was most probably exposed to which of the following during pregnancy?