Antenatal testing for cystic fibrosis during pregnancy is typically initiated by which gestational age?

• A. 32 weeks gestation
• B. 20 weeks gestation
• C. 12 weeks gestation
• D. 36 weeks gestation

Answer: (A)

This question is about when to begin antenatal testing in a pregnancy at risk for cystic fibrosis to support planning for delivery and newborn care. If there is known CF risk (such as a partner being a carrier or a previous affected child), invasive prenatal diagnostic testing (like CVS or amniocentesis) is done earlier in pregnancy to determine the fetus’s CF status. In contrast, antenatal testing aimed at ongoing surveillance and arranging neonatal care is typically started in the late second/early third trimester, around 32 weeks. Starting at this time allows enough lead time to confirm results, coordinate delivery at a facility equipped for CF care, and organize postnatal evaluation and management for the newborn, while not delaying planning too late or aiming for testing that would have already been completed earlier. Earlier gestations (12 or 20 weeks) correspond to the diagnostic window, not the routine antenatal surveillance for CF care planning, and waiting until 36 weeks risks missing optimal timing for arranging specialized newborn care.