A newborn's blood has more than double the adrenaline of the mom who just gave birth to him. So when you see a baby lying there minutes after delivery with his hands behind his head like he's at a cabana in Cabo, you're watching a kid come down off the biggest rush of his life so far. A Swedish pediatrician named Hugo Lagercrantz spent years measuring this, and he's the one who coined the phrase "the stress of being born." His group found that babies born vaginally had about 10 times the noradrenaline in their cord blood compared to babies delivered by planned C-section. Every contraction squeezes the baby and briefly cuts into his oxygen supply, and his body answers by dumping stress hormones. He needs that flood to survive the next few minutes. Here's why. For nine months his lungs were full of liquid. A baby's lungs actually pump fluid into themselves in the womb because that's how they grow, which works great right up until the second he needs to breathe air. The adrenaline from labor flips a switch in the lining of the lungs, and they start soaking that fluid back up right before the first breath. Scientists bred mice missing that switch, and the pups died after birth because they couldn't clear their lungs. The same rush breaks down his stored fat and sugar for energy, since the umbilical cord just stopped feeding him. It even keeps his pupils wide open under bright hospital lights. Once all that's done, babies settle into what researchers call the quiet alert state, where the body goes still and the breathing evens out. In one study that tracked newborns minute by minute, they spent about 40 of their first 60 minutes in it. Then comes sleep, and babies get more deep sleep on the day they're born than on the day after, which researchers think is recovery from birth itself. And that white stuff in his hair is called vernix. As far as scientists know, only human babies make it, and almost a third of the proteins they've found in it attack germs directly. So he came out wearing his own antibacterial lotion, and now he's sleeping off a hormone rush that kept him alive. Honestly, he earned the pose.