The term fetal development refers to the approximately 39 weeks a baby grows in a mother’s womb. Typically, fetal development begins once the father’s sperm fertilizes the mother’s egg. The fertilized egg, called a zygote, undergoes a series of changes as it grows into a blastocyst, an embryo and a fetus. In the early stages of the fetal development the zygote travels to the uterus and attaches to the uterine wall where it continuously divides.

For instance, the outer cells develop in the placenta which produces hormones that help maintain the pregnancy, according to Merck Manual Home Editionhttp://www.merckmanuals.com/home/sec22/ch257/ch257c.html. Once the cells are finished dividing, the embryo fetal development stage begins.

The embryo development begins in the week five of the pregnancy and continues to week 10. During the five weeks, many of the major organs begin forming. For instance, in week five the heart, gastrointestinal tract, brain and spinal cord begins developinghttp://http://www.nlm.nih.gov/medlineplus/ency/article/002398.htm. As the fetal development continues, the embryo starts developing arms, hands and legs.

The official term for the advance stage of pregnancy is called fetal development. Fetal development starts in week 11 and continues to week 39. During this period the embryo officially becomes a fetus. As the fetus continues to grow, it everything builds on everything that happened in the embryo stage. For example, rapid brain development begins and bones form. The mother can feel the fetus begin moving. The fetus also hits other milestones like gaining weight and practicing how to breathe.