Unborn Child's Development

Day 1: conception: all 46 human chromosomes present; unique human life begins. Day 6: embryo begins implanting in the uterus Day 22: heart begins to beat with blood often of a different type than the mother's Week 5: eyes, hands and feet begin to develop Week 6: brain waves detectable; mouth, lips present Week 7: eyelids and toes form; nose distinct

Week 8: all body systems present; bones begin to form; swims with a natural swimmer's stroke Weeks 9 and 10: fingernails develop; baby can suck his or her thumb, kick, curl toes, bend fingers Week 11: baby can smile; begins to breathe amniotic fluid Week 17: baby can have dream (REM) sleep Four to five months: grows to eight to ten inches in length Six months: can recognize his mother's voice; frowns, squints, and grimaces Seven to eight months: eyelids open and close; eye teeth are present Nine months: of 45 generations of cell divisions, 41 have taken place; child triggers birth

"Development can be divided into prenatal and postnatal periods, but it is important to understand that human development is a continuous process that begins at fertilization." - Professor Keith L. Moore Before We Are Born, ed 3, p.1