pregnancy and birth

After fertilization, the zygote travels towards the uterus, during this the zygote will divide several times through mitosis to form an embryo.

In the uterus, the embryo implants in the thick lining of the uterus and continue developing.

Until birth, 9 months pass.

Most organ development occurs within the first 12 weeks, in this same range of time the embryo gets its nutrients through diffusion through the endometrium.

When all organs are in place, the placenta has formed, and the embryo is now called a fetus.

The remaining weeks are used for the growth of the fetus in its size.

The fetus is surrounded by an amniotic sac containing amniotic fluid which is mainly made up of its mother’s blood plasma. The purpose of the amniotic sac is to protect the fetus from bumps in the abdomen.

The umbilical cord is the jointure for the blood supply and the placenta, exchanging nutrients and getting rid of the fetus’ waste products.

The placenta

During gestation, the fetus develops and grows thanks to gaining glucose, amino acids, fats, water, and oxygen from the mother’s blood.

The blood of the fetus and the blood of the mother flow oppositely in the placenta so that they do not mix.

The fetus blood connect to and from the placenta by the umbilical cord.

The mother blood, apart from giving the fetus nutrients, takes the waste products from the fetus’ blood in the places, products like carbon dioxide and urea so that they do not build up to dangerous levels.

Every transport of molecules across the placenta occurs through diffusion, and the placenta adapted to this by:

• Large surface area

• Thin wall

The placenta works as a barrier to prevent pathogens getting into the fetus’ blood. But not every pathogen is stopped from passing. Which is the reason why any pregnant person is advised not to smoke during gestation, since nicotine CAN PASS THROUGH THE PLACENTA.

After birth, the umbilical cord is cut, and this is tied off to prevent bleeding. Also after birth, the placenta detaches from the uterus wall being pushed out through contractions in the muscular wall of the uterus - known as afterbirth.

Stages of birth

• Muscles in the uterus wall contract

• Amniotic sac breaks

• Cervix dilates

• The baby passes through the vagina to the outside.

• The umbilical cord is tied and cut.

• Afterbirth is delivered.

Antenatal care

• Diet of the mother should contain: Iron, calcium, proteins, carbohydrates, and lipids. Plus, folic acid to prevent developmental issues.

• Exercise.

• Avoiding infections and drugs.

• Advised not to eat raw meat.

Breastfeeding

During pregnancy the mammary glands enlarge and become prepared to secrete milk.

Shortly after birth, the mother will be stimulated to release milk due to the sucking action of the baby at the breast.

Som human mothers struggle to breastfeed so they opt for formula milk in a bottle