Can you tell if you're carrying a boy or a girl? One hint may come from the size of your baby – boys tend to be slightly heavier than girls. Babies at week 39 weigh between 3kg and 3.2kg and continue to build the fat stores that will help regulate body temperature after birth.Your baby's organ systems are fully developed and in place, but his lungs will be last to reach maturity. Even after your baby is born, it may take a few hours before he establishes a normal breathing pattern.
