Pregnancy Week by Week: 38 Weeks Pregnant

What's happening when you're 38 weeks pregnant? At about seven pounds and 21 inches long on average, your bun in the oven is now a fully cooked loaf of bread. He’s still got some work ahead of him, though, before he makes his big debut. He’ll lose the vernix – that waxy coating that’s been protecting his fragile fetal skin from amniotic fluid – and he’ll shed any remaining lanugo – the fine hair that was temporarily covering his body. 

Wondering where it all goes? Once the vernix and lanugo are shed into the surrounding amniotic fluid, your baby ingests them along with other waste products such as bile, urine, and old cells. These all percolate in those teeny intestines, ultimately winding up in his diaper as the very first, very dark green, and very sticky poop known as meconium. Might not be a tasty first meal for him, but it’s pretty efficient!

Also gearing up for the big day are your baby’s lungs now fully mature, but still producing surfactant in large quantities to ensure that the transition from watery womb to wondrous world is a smooth one. Your little diver’s been practicing his breathing moves underwater for months, and he’s just about ready to try the real thing.

As baby prepares for life on the outside, the placenta, his lifeline in this underwater world, starts to slowly deteriorate. Not to worry! It still has plenty of life left to sustain your little one until the big day.

Did You Know?

The caffeine a pregnant woman consumes crosses the placenta to the baby, which their still-developing digestive system is unable to fully metabolize. What’s more multiple studies have shown that caffeine can cause birth defects, preterm delivery, reduced fertility, and also increase the risk of low-birth weight.