DEVELOPMET Session 16 Flashcards
How does the fetal circulation occur ?
- Umbilical vein carries oxygenated blood to the fetus
- umbilical vein then enters the liver and joins the ductus venosus , which empties into the inferior vena cava
- The mix blood enters the heart ( right atrium ) , most of it is shunted to the left atrium through the foramen ovale.
- some blood that enter the right atrium is pumped into right ventricle and the pulmonary truck .
- it then joins the aorta by way of the ductus arteriosus
What connects the 2 umbilical arteries carrying oxygen poor blood to the placenta ?
- The iliac arteries
At birth , what can inflation of lungs cause ?
- Increased blood flow from the heart to the lungs
What can a increase in blood flow from the pulmonary veins to the left atrium causes ?
- It can increases the pressure in the left atrium , causing a fall to cover the foramen ovale
what are fontanelles and when do they appear?
- They are six large membranous areas in the skull that appear in the beginning of month 3
When can you clearly hear the heartbeat of a fetus ?
- During the fourth month
What is a lanugo ?
- it is a wrinkled , translucent skin which is covered by a fine down
What is a vernix caseosa?
- It is coating with a white cheese like substance which protects the delicate skin from the amniotic fluid
When does the fetus usually rotate so that the head is pointed toward the cervix ?
- during the 8-9 months period
What is Braxton Hicks contractions ?
- False labor
What positive feedback mechanism is used during labor ?
- Uterine contractions are induced by a stretching go the cervix , which also causes the release of oxytocin from the posterior pituitary gland
- which then stimulates the uterine muscles to contract which pushes the fetus downward and the cervix stretches even more
What is Parturition ?
- The process of giving birth
What is effacement ( cervix dilatation ) ?
- This is when the cervical canal disappears due to uterine contractions
When does the first step of parturition end ?
- When the cervix is dilated completely
What is an Episiotomy ?
- An incision to enlarge the vaginal orifice