Stages of fetal development

Stages of fetal development

The first stage

  • First and second week of pregnancy: The first week of the first day of the last menstrual cycle begins. At the end of the second week, the egg separates from the ovary and meets the sperm at the beginning of the third week.
  • Third week of pregnancy: The fetus at this stage is a ball of cells containing DNA taken from the parents, which determines sex, eye color, and other attributes.
  • Fourth week of pregnancy: The ball becomes a poppy seed, and over the next six weeks, all the child’s organs begin to develop, some of which will begin to work.
  • Fifth week of pregnancy: The heart of the fetus starts beating at twice the rate of adult human.
  • Sixth week of pregnancy: facial features such as eyes and nose begin to form, and very small parts show where the arms and legs will develop later.
  • Eighth week of pregnancy: The arms and legs grow, and the fingers, nose and upper lip appear and begin to move slightly, but the mother will not feel his current movement, and it is 1.59 cm long.
  • Ninth week of pregnancy: The formation of the eyes is completed, but the eyelids will remain closed, and the shape of the outer body is similar to the human form.
  • Tenth week of gestation: Vital organs, such as the kidneys, intestines, brain, and liver begin to work and the fingers and toes begin to appear more.
  • Eleventh week of pregnancy: The bones begin to develop sclerosis, and the reproductive system develops.
  • Twelfth week of pregnancy: The fetal heartbeat can be heard when examined by a specialist doctor. It is about 5.08 cm long and weighs about 14.2 grams.

The second phase

  • Fourteenth week of pregnancy: The child’s kidneys begin to produce urine and release it into the amniotic fluid.
  • 15 to 18 weeks of gestation: The baby’s skin is transparent and begins to move. The liver and pancreas begin to secrete fluids.
  • Week 19 to 21: At this stage the child can hear, and the mother feels the movement at the bottom of her abdomen.
  • Twenty-two weeks of pregnancy: the eyebrows appear, the child is more active with the development of muscle growth, and the doctor can hear the fetal heartbeat by his head.
  • Twenty-third to twenty-fifth of pregnancy: The bone marrow begins to make blood cells, the lower airways develop to the baby’s lungs, and the baby begins to store fat.
  • Twenty-sixth week of gestation: All parts of the child’s eyes are developed. The eyebrows and eyelashes are well-formed. Reactions to high sounds occur. An air sac is formed in the baby’s lungs, but the lungs are still not ready for ectopic functioning.

third level

  • Week 27 to 30: The child’s brain grows rapidly, and the nervous system is developed enough to control some of the body’s functions.
  • Week thirty-four to thirty-four: The child grows quickly and earns a lot of fat, and begins the child’s body stores iron, calcium and phosphorus.
  • Thirty-fifth to thirty-seventh week: Blood vessels and heart are fully formed, weighing about 2.5 kg.
  • Week thirty-eight to forty: where the head hair is rough and your name, the baby can be born at any moment.

Date of birth of fetus

The date of the fetus’s birth can be calculated by using the Naegele’s Rule, which adds a full year to the first day of the last menstrual cycle, then subtracts three months from the date, and increases seven days.