During the 42 weeks of pregnancy, our babies rapidly evolve—from a pair of zygotes—to an aquatic life in the womb—and finally, one breathing in the world. Being almost a miracle in itself, the human lung forms early in fetal lung development, appearing in the embryonic phase at the fourth or fifth weeks of gestation. Branching to the left and right, they bud as two seeds would.
Phases of Development
After the passing of the embryonic phase, it is in the 17th week of the pregnancy that our two organic buds each grow a respiratory system, respectively. Capillary vessels sprout up and down, supplying the blood that will transport oxygen into the fetus’s nascent, growing brain. By the canalicular phase, there exists a clear barrier between air and blood flowing in the womb. Carbon dioxide and other gases are now able to be evacuated from respiratory capillaries in the lungs.
Saccular and Beyond
The saccular phase, at 36 weeks of pregnancy, is when the fetus’s lungs are said to be fully developed. At this final stage of fetal lung development, the lungs have begun producing surfactant—a soapy substance meant to preserve lung tissue and prevent it from damage during exhalations. As Baltimore lawyers know all too well, it is at this critical stage that a fetus is most prone to birth injury and the danger of cerebral palsy.
Without an adequate production of surfactant, a fetal lung cannot be said to be mature. Doctors specializing in prenatal care are instructed to order an amniocentesis, should they suspect the potential for a premature pregnancy. If it appears that a mother and her baby will enter labor prematurely, an injection of steroids can be administered to accelerate the development of the baby’s lungs. By neglecting to act on these warnings, a doctor may be deemed guilty of prenatal malpractice.
When a mother and her baby have been deprived of antenatal steroids, she and her child can face an unsafe delivery. Immature lungs ultimately result in less oxygen flowing to a newborn’s brain (called hypoxia)—manifesting as respiratory distress syndrome, transient tachypnea, or even periventricular leukomalacia. Lacking a steady supply of oxygen during pregnancy, a baby is vulnerable to birth injury and later diagnosis of cerebral palsy.