During which month of prenatal development can pulmonary surfactant first be produced?
a. Second b. Ninth c. Fourth d. Seventh
The correct answer and explanation is:
The correct answer is d. Seventh.
Pulmonary surfactant, which is essential for lung function after birth, starts to be produced around the seventh month of prenatal development. This surfactant is a complex mixture of lipids and proteins that reduces surface tension within the alveoli, preventing their collapse and making it easier for the baby to breathe once born.
Before this, the lungs are still developing, and the alveoli (the tiny air sacs where gas exchange occurs) are not yet capable of efficient gas exchange. During the early stages of pregnancy, the lungs are primarily in the process of forming and branching. However, it is around the 24th week of pregnancy (around the sixth month) that the lungs begin producing small amounts of surfactant. This production increases during the seventh month as the fetus approaches term.
By the ninth month, there is a sufficient amount of surfactant, and the lungs are nearly ready for breathing air outside the womb. If a baby is born prematurely, especially before the seventh month, there is a higher risk of respiratory distress syndrome (RDS) because the lungs may not yet have enough surfactant. In such cases, medical interventions, such as administering surfactant therapy, may be needed to assist the baby’s breathing.
In summary, the seventh month is when pulmonary surfactant production significantly ramps up, preparing the lungs for the demands of breathing after birth.