Fetal Development and Birth

Fetal Development

After fertilisation occurs, ciliated cells help transport the fertilised egg through the fallopian tube and into the uterus. Once it reaches the uterus, the fertilised egg implants into the uterine wall and begins to divide and grow.

  • This process is known as implantation

Some of the cells produced during this process will form the placenta. This is an organ that attaches to the uterine wall and provides nutrients and oxygen to the growing fetus.

The fetus relies on its mother for:

  • Important nutrients (e.g. food and water)
  • Oxygen for respiration
  • Protection
  • The removal of carbon dioxide and other waste products

The amniotic fluid, a liquid that surrounds the baby in the womb, provides additional protection, support and nourishment.


The placenta is a temporary organ that develops in the uterus during pregnancy. It is responsible for providing nutrients and oxygen, and removing waste products from the fetus through the umbilical cord.

The placenta attaches to the uterine wall and is connected to the fetus by the umbilical cord.

The blood of the mother and the fetus does not mix directly. Instead, the placenta allows for the exchange of substances across the two blood supplies.

  • Nutrients and oxygen diffuse from the mother’s blood to the fetus’s blood.
  • Waste products, such as carbon dioxide, diffuse from the fetus’s blood to the mother’s blood.


Pregnancy, otherwise known as gestation, is the period of time in which the baby develops inside the mother’s uterus. This typically lasts for around 40 weeks.

At the time of birth:

1. The cervix (the lower part of the uterus), relaxes and widens to allow the baby to pass through.

2. The walls of the uterus contract, helping to push the baby through the vagina and out of the body.

3. The umbilical cord, which connects the baby to the placenta, is cut once the baby is born.

  • The placenta is also expelled from the body during this process.

Effects of Maternal Lifestyle

A mother’s lifestyle can have a big impact on her baby’s health. Substance abuse, such as smoking or drinking alcohol, can pose a risk to the baby’s health.

  • Smoking during pregnancy can reduce the amount of oxygen in the mother’s bloodstream, potentially leading to premature birth.
  • Alcohol consumption can harm the baby’s nervous system.

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