Fœtus

Fœtus

A fœtus (or fetus) is a stage in the prenatal development of viviparous organisms. In humans, the fetal stage begins at the end of the embryonic stage, which is typically at the end of the 8th week of gestation, and continues until birth.

Development

The development of the fœtus is a complex process that involves the growth and differentiation of cells, tissues, and organs. During this stage, the fœtus undergoes significant changes, including the development of the central nervous system, cardiovascular system, and musculoskeletal system. The fœtus also begins to exhibit movements and reflexes.

First Trimester

In the first trimester, the fœtus grows rapidly. By the end of the 12th week, the fœtus has developed all major organs and structures. The placenta also forms during this period, providing nutrients and oxygen to the fœtus and removing waste products.

Second Trimester

During the second trimester, the fœtus continues to grow and develop. The skeletal system begins to harden, and the fœtus starts to develop hair, eyelashes, and eyebrows. The nervous system becomes more complex, and the fœtus begins to respond to external stimuli.

Third Trimester

In the third trimester, the fœtus undergoes rapid growth and maturation. The lungs mature, and the fœtus gains weight in preparation for birth. The brain continues to develop, and the fœtus's movements become more coordinated.

Fetal Health

Monitoring the health of the fœtus is crucial during pregnancy. Various methods, such as ultrasound, amniocentesis, and non-stress tests, are used to assess fetal well-being. Conditions such as fetal distress, intrauterine growth restriction, and congenital anomalies can be detected and managed with appropriate medical care.

Birth

The fetal stage ends with birth, which marks the beginning of the neonatal period. The transition from fetal to neonatal life involves significant physiological changes, including the initiation of breathing and the closure of fetal circulatory shunts.

Related Pages

• Embryo
• Pregnancy
• Prenatal development
• Neonatal
• Placenta
• Ultrasound