Question

The swallowing and breathing reflex is NOT seen in the fetus until which gestational age?

• A. 14 weeks
• B. 12 weeks
• C. 16 weeks
• D. Appears in all the above periods

Hint:

Breathing and swallowing motions begin by 13 to 14 weeks, so they are absent at 12 weeks.

Answer 1

The Correct Option is B

Step 1: Trace fetal behavioural milestones. Muscle contractions first appear around 8 weeks, followed soon by lateral flexion movements. Breathing and swallowing motions then appear by about 13 to 14 weeks of gestation.

Step 2: Apply to the question. Since breathing and swallowing motions begin at roughly 13 to 14 weeks, they are NOT yet present at 12 weeks. So the reflex is not seen at 12 weeks, which is the answer.

Step 3: Why the others are wrong. By 14 weeks and 16 weeks these motions have already appeared, so they cannot be the period in which the reflex is absent. The grasp reflex appears at 17 weeks and eye opening around 26 weeks, confirming the timeline.