Baby Development Tracker
- Week 1 - 4The first day of menstrual bleeding is considered the official start date of pregnancy and the 40 weeks of pregnancy are calculated from this date. At 1-4 weeks pregnant, heart and primitive circulatory system rapidly form. While still in its beginning stages, this is the very life support system that will carry your child throughout his or her life.
- Week 5 - 8Your baby is an embryo consisting of two layers of cells from which all his or her organs and body parts will develop.
- Week 9 - 12Your baby is now about the size of a kidney bean and is constantly moving. The baby has distinct, slightly webbed fingers.
- Week 13 - 16By now your baby is around 7 to 8 centimetres (3 inches) long and weighs about the same as half a banana. His or her tiny, unique fingerprints are now in place.
- Week 17 - 20Your baby is now about 13 centimetres ( 5.5 inches) long and weighs 140 grams (5 ounces). The baby's skeleton is starting to harden from rubbery cartilage into bone.
- Week 21 - 24Eyebrows and eyelids are now in place. Your baby would now be more than 27 centimetres (10.5 inches) long if you stretched out his or her legs.
- Week 25 - 28Your baby weighs about a 660 grams (1.5 pounds). The baby's wrinkled skin is starting to smooth out as he or she puts on baby fat.
- Week 29 - 32By now, your baby is more than 40 centimetres (15 inches) long, and can open and close its eyes and probably see what's around him or her.
- Week 33 - 36Your baby now weighs around 2.2 kilos (4.7 pounds). The baby's layers of fat are filling out, making him or her rounder, and its lungs are well developed.