Take a look at any weekly fetal development chart, fetal models, or a fetal progress chart and you can get some amazing insight into the way a baby develops in the womb. Long before a new mother goes through the process of giving birth, incredible things are happening inside:
Your weekly fetal development chart will likely begin by showing you the fertilization process. This happens when a woman ovulates and the egg is fertilized by sperm. Once fertilization has happened, the egg begins dividing rapidly as it travels down the fallopian tube and enters the uterus. Approximately three weeks in, a tiny ball made up of multiple fertilized cells nestles in the lining of the uterus.
At the fourth week on the weekly fetal development chart, you’ll see that the ball of cells is officially referred to as an embryo. This is the first point at which a mother will typically be able to get a positive result from a home pregnancy test.
At the fifth week, the baby’s circulatory system is beginning to form, and its tiny heart begins to beat. If you look at your weekly fetal development chart at this point, the pictures look a bit more like a tadpole than a human child. Yet the child already has everything that makes it truly human.
At the sixth week of development, the nose, mouth, ears, intestines, and brain are beginning to develop. The lungs are beginning to form, the pituitary gland is forming, and muscles and bone are beginning to grow.
At the seventh week of development, the baby will have doubled in size from the week before and arms, legs, hands, and feet will have begun to emerge.
At this week, the pictures on the weekly fetal development chart will show something recognizable as a human being. The baby has started to move, though the mother cannot feel it yet, and eyes, hands, and feet are distinct.
At week nine, the basic physiology is completely in place all the way down to the baby’s earlobes. The heart has finished dividing into its four chambers and the teeth are beginning to grow. Eyes are fully formed, but they will not open until 27 weeks.
These four weeks are the end of the first trimester, and at the end of this time every detail of the human being has been formed, including fingernails and more than two million eggs if the baby is a girl. The baby also has reflexes and can feel pressure if someone pokes the mother’s stomach.
During these weeks, a baby puts on weight very rapidly. All the baby’s senses are developing and the baby will be able to hear it’s mother’s voice. Soft cartilage hardens to bone, and the baby is moving quite a bit, though most mothers cannot feel it at this point.
During this period, the baby’s own digestive system begins working and they will start passing waste. Hair begins to come in, and the pictures on the weekly fetal development chart look more like a newborn.
These two weeks are crucial. This is when the baby’s eyes open, when the baby begins inhaling and exhaling and developing its lungs, and brings an end to the second trimester.
During this period of rapid growth, the mother is gaining about a pound a week and half of that is going to the baby, who is developing a protective layer of fat. The baby can turn its head, sense light, and is beginning to run out of room in the uterus.
At this point, most babies with no other health problems will do well even if born prematurely. The kidney and liver are working well, and the baby’s body is fine-tuning itself.
By week 39, the baby has developed completely but is busy putting on fat. It’s time to be born, and the baby will be considered late if it goes beyond 41 weeks.
The process of giving birth is one of the most amazing things that happens in the natural world. From week one right up until birth, babies are developing and growing in incredible ways.