28. Pregnancy and Human Development

Match the correct time period of gestation with the prenatal period of development:

________Pre-embryonic period

________Fetal period

________Embryonic period

a. Weeks 3–8

b. Weeks 1–2

c. Weeks 9–38

Match the fetal developments to the correct month of gestation.

________Month 3

________Month 4

________Month 5

________Month 6

________Month 7

________Months 8 and 9

a. A downy hair called lanugo develops.

b. Organs specialize and grow.

c. Lungs begin to produce surfactant.

d. The heartbeat can be heard with a stethoscope.

e. Fetus turns to the vertex position.

f. Ossification begins in most bones.

Match the structures found in the fetal circulation with what each fetal structure becomes after birth:

________Foramen ovale

________Ductus arteriosus

________Ductus venosus

a. Ligamentum venosum

b. Fossa ovalis

c. Ligamentum arteriosum

The prenatal period typically lasts 38 weeks. From the clinical viewpoint, a pregnancy typically lasts 40 weeks. What is the reason for this difference?

Why do most spontaneous abortions occur in the first trimester?

A new allergy medicine has just been approved by the Food and Drug Administration (FDA); however, it is not approved for pregnant women. What might be the reason for this exclusion?