During week 39, your baby's brain is continuing to develop and mature to help control her inner workings and the processing of her impending responses to the outside world. Baby is also working on creating functional tear ducts, and while she will be able to cry shortly after birth, she won't be producing tears for several weeks.
Labor and delivery will be as difficult for baby as it is for you. Moving down the birth canal and essentially being pushed out of the only world she has ever known will take energy and put a certain, though expected, amount of stress on the baby's body. No need to fear, for most babies this process moves smoothly, and baby will be no worse for wear when all is said and done, and she is resting in your arms.
After the baby is born, you might notice she is covered in remnants of the vernix and globs of blood and other fluids. This goop is normal, so don't be shocked. Other things you might notice after birth will be baby's chubby cheeks and a lighter skin tone, which will change for several weeks until her pigment becomes what it is meant to be. Eye color is also likely to change as the irises often get darker after birth. However, brown-eyed babies are unlikely to be blue-eyed children.
- American Pregnancy Association - Week 39
- American College of Obstetricians and Gynecologist - How Your Fetus Grows During Pregnancy