Human Development – Lecture 25 – 2nd and 3rd trimester,
(complications) birth
Fertilization to birth
Fertilization
1st; embryogenesis and fetal development, all organ systems emerge
2nd; organ development, at the end the fetus appears human
3rd; fetus grow rapidly and all organs are functioning
Birth
Embryo (1-8 weeks) → Fetus (from 9 weeks until birth)
Prenatal development;
• Differentiation; changes in genetic activity. Start by embryogenesis
• Development; change in anatomy and physiology
Pregnancy takes 10 months; 40 weeks after last menstruation, 38 weeks after
fertilization.
First 12 weeks pass smoothly, solid foundation. Likelihood for miscarriage drops after
12 weeks.
Fetal development during 2nd trimester;
Fetus kicks, moves and turn.
Respond to specific stimuli
Sleeps or wakes up.
Eyes and ears are in place, fetus can hear
Sex organs developed (after 7e week)
Vernix to protect the skin
Hair starts to grow
Fat tissue appears
Brain in main growth pas at 5th month
Fingers and toes completely
Fetal development during 3rd trimester;
Lungs and brain still developing.
Begins to descend (afdalen)
Can see and hear
Lungs are the last to fully grown
The body of the mother;
Growing fetus is dependent on organ systems of the mother for nutrition, respiration
and secretion.
• Increased speed of respiration
• Increased intake nutrients and vitamins
• Increased blood volume
• Increased glomerular filtration (vanuit nieren)
• Decreased systemic vascular resistance
(complications) birth
Fertilization to birth
Fertilization
1st; embryogenesis and fetal development, all organ systems emerge
2nd; organ development, at the end the fetus appears human
3rd; fetus grow rapidly and all organs are functioning
Birth
Embryo (1-8 weeks) → Fetus (from 9 weeks until birth)
Prenatal development;
• Differentiation; changes in genetic activity. Start by embryogenesis
• Development; change in anatomy and physiology
Pregnancy takes 10 months; 40 weeks after last menstruation, 38 weeks after
fertilization.
First 12 weeks pass smoothly, solid foundation. Likelihood for miscarriage drops after
12 weeks.
Fetal development during 2nd trimester;
Fetus kicks, moves and turn.
Respond to specific stimuli
Sleeps or wakes up.
Eyes and ears are in place, fetus can hear
Sex organs developed (after 7e week)
Vernix to protect the skin
Hair starts to grow
Fat tissue appears
Brain in main growth pas at 5th month
Fingers and toes completely
Fetal development during 3rd trimester;
Lungs and brain still developing.
Begins to descend (afdalen)
Can see and hear
Lungs are the last to fully grown
The body of the mother;
Growing fetus is dependent on organ systems of the mother for nutrition, respiration
and secretion.
• Increased speed of respiration
• Increased intake nutrients and vitamins
• Increased blood volume
• Increased glomerular filtration (vanuit nieren)
• Decreased systemic vascular resistance
