A 33-year-old woman is 32 weeks pregnant and

experiences premature amniotic fluid leakage and preterm labour. The woman is

given tocolytics (medication that inhibit uterine muscle activity). Their

administration stops or relieves the contractions of the uterus, thereby

delaying premature labour. The main benefit of tocolytic treatment is mainly

short-term, i.e. delaying preterm birth by two to seven days. The reason for

tocolytic treatment is to buy time for transport of the woman and baby to a

specialized centre and for time for administration of corticosteroids to induce

lung maturity of the fetus. One important factor in lung maturity is sufficient

surfactant production. Which lung cells produce it?