“One last surge and your baby will be here. You are almost there.”
A final grunt, and her baby’s shoulders and body are moved between the worlds into the waiting hands of a care provider, her partner, or the mother herself.
These two, mother and baby, know each other so intimately, yet are meeting for the first time.
A moment of silence. A small intake of breath. Then, a cry.
This child who has only known fluid, is now one of air.
It is just seconds of time. From the outside, we see barely anything, but internally, these seconds bring the most complex changes our bodies ever do.
When inside the womb, a baby’s blood circulation differs from ours in one big way: a placenta. Instead of receiving oxygen and exchanging gases through the lungs like we do, the blood of an unborn baby is transported to the placenta via the umbilical cord, where it releases waste products and receives oxygen before travelling back to the baby’s body. This makes the first minutes of a baby’s life especially profound, because they must transition their entire circulation system from one that includes a placenta to one that does not. Before birth, their lungs are fluid-filled, ‘deflated’ and receiving very little blood flow, but they’re about to be essential to keeping them alive. How does this change happen?
The stimulation and ‘shock’ of birth from warm, dark enclosed space into colder, brighter open space triggers the baby’s reflex to breathe. Between the pressures of the incoming air and of the first cry, the fluid that has been sitting in the lungs gets pushed into the surrounding tissue, allowing air to inflate the lungs.
All of a sudden the baby has access to more oxygen than they have ever had before. More blood starts flowing to the lungs and less to the placenta. The placenta has less and less blood to return to the baby, and slowly the umbilical cord stops pulsing. At different places through the blood stream, including in the heart itself, little ‘shunts’ (like gates) close, permanently altering the direction the baby’s blood flows through its system.
Their transition to the world is complete.