Development in the Prenatal Stage

Stages of development
Prenatal development refers to a child’s development before birth.  The period of development between conception and birth is known as gestation.  Pregnancy, or gestation, usually lasts between 37 and 41 weeks.  Prenatal development is divided into the germinal, embryonic, and fetal stages.

• Germinal Stage: weeks 1-2 after fertilization
  • During this stage, the zygote, or single-celled organism resulting from the fusion of a sperm and egg that is the very beginning of the child, rapidly divides to become bigger and more complex.  At about 10 days after fertilization, the embryo implants into the wall of the uterus.
• Embryonic Stage: weeks 3-8 after fertilization
  • During this stage, most of the embryo’s organs and systems develop rapidly.  At 8 weeks, when the embryo becomes known as a fetus, his or her heart, eyes, ears, brain, digestive system, respiratory system, and facial features are all largely developed.
• Fetal Stage: week 9-birth
  • During this stage, the fetus grows rapidly and continues to develop the “finishing touches” such as fingernails and eyelids.  The fetus moves around inside the uterus while growing and continuing to develop until he or she is ready to be born!

For more details on prenatal development, see the following video: https://www.ehd.org/your-life-before-birth-video/ 

Monitoring Prenatal Development 

• Not that long ago, almost the only decision parents had to make about their babies before birth was the decision to conceive. 
  • What happened in the next months was beyond their control 
• Women under the age of 35 years of age that have no obvious risk factors would usually use ultrasounds and blood tests to receive a risk assessment of their baby’s health 
• Progress is being made in the use of non-invasive procedures (ex. Ultrasounds, blood tests) to test for chromosomal abnormalities  
  • Screening is most effective when begun during the first trimester 
• Amniocentesis - a procedure in which a sample of amniotic fluid is withdrawn for analysis
  • A tissue from the membrane surrounding the fetus in removed and analyzed 
• Embryoscopy - the insertion of a tiny viewing scope into the mother’s uterus through the abdominal wall for a direct look at the embryo can help diagnose non-chromosomal disorders
• Good prenatal care can give every child the best possible chance for entering the world in good condition to meet the challenges of life outside the womb