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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A 38-year-old G1P0 woman presents to her obstetrician for a prenatal visit. She reports feeling well and has no acute concerns. She is currently at 28 weeks gestation previously confirmed by ultrasound. She takes her folate supplements daily. On physical exam, the uterus is soft and globular. The top of the uterine fundus is found around the level of the umbilicus. A fetal ultrasound demonstrates a reduced liver volume and subcutaneous fat with relative sparing of the head. Which of the following is most likely the cause of this patient's ultrasound findings?
assistant
Cigarette smoking