Movement allows mvt of baby and mvt of cord if nuchal

Movement: allows mvt of baby and mvt of cord; if nuchal cordx1 means cord was around the
baby’s neck one time. Amniotic fluid does not have waste substances; baby can swallow it.
 Yolk sac-develops at about day 8 or 9 and forms primitive RBCs for baby until liver starts at 6 weeks
 Umbilical cord
o formed from the amnion
o 1 large vein, and 2 smaller arteries
 2 vessels associated with congenital anomalies; send this baby for ultrasound (kidney;
heart; something we can’t see); 2 vessels doesn’t cause it but it can be associated
o Wharton’s jelly-a specialized connective tissue that surrounds the blood vessels in the umbilical
cord; prevent compression/kinking of the umbilical cord; no sensory innervation
o Central insertion in the placenta is considered normal
 When the cord is attached to the center, the vessels need to transverse the placenta in
order to have optimum transport of nutrients.
o Nuchal cord-when the cord encircles the fetal neck
o Length of cord: avg. length of baby is 20” (18-22); cord length 20-22”; width is about 1”; large
cords seen in GDM; moms who have suffered nutritionally or used drugs look weathered
o vein brings oxygenated blood from mom to the baby; 2 arteries bring deoxygenated blood to the
placenta
b/c mom’s liver takes control of filtering blood in utero, taking care of bilirubin; baby should, therefore, not be
born jaundiced; a baby that has been through a traumatic delivery (caput: blood under skin on skull) baby would
be at increased risk of jaundice.
Twins=2 questions
 Fraternal ( Dizygotic ) =arise from two separate eggs and 2 sperm; may not be the same gender; no more
similar than siblings born separately; 2 placentas, 2 chorions, and 2 amnions
o Studies indicate that dizygotic twins occur in certain families, possibly because of genetic factors
that result in elevated serum gonadotropins and thus double ovulation
o Occurrence increases which maternal age and then drops off after 35 yo
 Identical ( Monozygotic ) = develop from a single fertilized ovum (1 egg and 1 sperm); they will always be
the same gender; something happens during the first eight days after fertilization and the cells divide
and form two separate humans; identical twins usually have a common placenta
Placental functions and fetal circulatory system=2 questions
Placenta
 Develops at the site where the embryo attaches to the uterine wall during the third week of embryonic
development
 means of metabolic and nutrient exchange btw baby and mom; no way a baby can survive w/o placenta;
if it separates completely the baby may not survive
o A woman who has had a miscarriage before 12 may be able to have miscarriage at home;
however, if past 12 weeks placenta is fully developed, dilation and curretage may be the tx
option of choice to make sure that no placental fragments are retained (which would be a risk
for infection)
 Has two parts:
a. maternal side (red and fleshy)/dirty dunkin: consists of the decidua basalis and its circulation;
covered by the amnion, which gives it its shiny appearance
b. fetal side (shiny)/shiny Schultz: consists of the chorionic villi and their circulation
Placenta: