Your baby now weighs about 250 grams (8.5 ounces) and measures around 15 cm (6 inches) crown to rump. They are becoming more active, with stronger kicks and movements that you can definitely feel! The baby's ovaries, if you're carrying a girl, contain about 6 million eggs at this stage. By birth, this number will decrease to about 1 million. These eggs are never reproduced, meaning the egg that becomes your baby is as old as you are! If you're having a boy, his testicles have been formed and secreting testosterone since around week 10. The external genitalia are continuing to grow, and the scrotal sac is now evident. Sensory development reaches a peak this week. The five senses – taste, smell, hearing, seeing, and touch – are improving as the nerve cells responsible for them develop in their specialized areas of the brain. A white, greasy coating called vernix caseosa is starting to appear on the baby’s skin. This protects the delicate skin from the amniotic fluid and helps regulate the baby's temperature. The baby is sucking and swallowing amniotic fluid, which helps with the development of the digestive system. They may even have a favorite position they like to curl up in.