A fetus born before the 37th week of gestation is called a...

• A. Post-term infant
• B. Premature infant
• C. Full-term infant
• D. Late-term infant

Answer: (B)

Being born before 37 weeks means the infant is premature. Gestational age is counted from the first day of the last menstrual period, and births before 37 weeks are classified as preterm because many organ systems, especially the lungs, are not fully developed yet. This is different from full-term births, which occur closer to the due date (usually around 39–40 weeks), and from post-term or late-term births, which happen after about 41–42 weeks. The key takeaway is that preterm/premature describes an early birth, which carries higher risks and typically requires specialized neonatal care.