Placenta/fetal circulation

• When does placenta begin to form?

• Implantation

• Why is the placenta so important?

It means fetal/maternal metabolic exchange

• By 20 weeks what does placenta do?

• Covers half the uterine surface

What is the function of placenta?

• Lungs for fetus

• Nutrition

• Excretion and storage 

  • Carbs

  • Proteins

  • Calcium

  • Irons

  • Fats

  • Vitamins

• Placenta is the maternal transfer of?

• Immunoglobulins

• What is hCG used for?

• Basis for pregnancy tests

• What is the purpose of progesterone?

• Maintains endometrium

• Decreases contractility of the uterus

• What is the purpose of estrogen?

• Stimulates uterine growth

• Stimulates myometrial contractility

• What is hPl?

• Increases amount of glucose in maternal blood

• Placenta function is determined by what?

• Maternal blood pressure

• What is supine hypotension>

When in supine position the pressure of the uterus compresses vena cava/aorta causing hypotension symptoms

• What is fetal circulation?

•  unique circulatory system of a developing fetus within the mother's womb

• What is ductus venosus?

• By passes the fetal liver

• Connects umbilical vein with inferior vena cava

• What is foramen ovale?

• Opening between right and left atria

• Right to left shunt

• What is ductus arteriosus?

• Bypass the lungs connection between pulmonary artery and aorta

• Path of least resistance

Why are shunts no longer needed after birth?

• Lungs are used for oxygenation

• Metabolism starts in liver

• No more circulation to placenta

• Changes in pressure and oxygen causes ducts to close