Pregnancy Flashcards
What are the 3 major blood vessels in the umbilical cord? Oxygenated or deoxygenated blood?
2 umbilical arteries – deoxygenated blood
1 umbilical vein – oxygenated blood
What are the trimesters of pregnancy?
T1: 1-14wks
T2: 14-28wks
T3: 28-42wks
What is a normal pregnancy term?
37-42wks
What are the symptoms of pregnancy?
- amenorrhea
- nausea & vomiting
- breast swelling & tenderness (pathophysiology: proliferation of secretory glands secondary to chorionic gonadotropin secretion)
- urinary frequency (pathophysiology: increased pressure on bladder caused by uterine enlargment)
- fatigue
- craving or aversion to certain foods
- weight gain
- linea nigra (darkening of midline abdominal skin) + areola hyperpigmentation
- constipation / bloating
Which trimester holds the highest risk of miscarriage?
T1
What is the GA for a preterm birth?
Less than 37wks 0/7days GA
What does GA stand for?
gestational age = fetal age calculated from 1st day of last menstrual period
What is the GA for a postterm birth?
More than 42wks 0/7 days GA
What is the normal duration of pregnancy?
40wks
What does GPAV stand for?
G = gravidity = total number of pregnancies (includes current, abortions, moles, multiple gestation = one pregnancy)
P = parity = number of births (can be divided into T term deliveries and P preterm deliveries)
A = abortions & ectopic pregnancies & miscarriages ending before 20wks GA
V = L = living / vivant
What is Goodell’s sign?
softening of the cervix (wks 1-6)
What is Chadwick’s sign?
bluish discoloration of the cervix and vagina secondary to pelvic vasculature engorgement (wks 6-8)
What is Hegar’s sign?
softening of the uterine isthmus (wks 6-8)
What are the vascular patterns associated with pregnancy?
telangiectasias & palmar erythema on palms
What is choloasma?
choloasma = melasma
benign hyperpigmentation of the face associated with pregnancy (and certain medications)
How is pregnancy diagnosed?
b-hCG in urine or blood
ultrasound
What is b-hCG?
b-hCG = human chorionic gonadotropin = hormone produced by placental trophoblastic cells
What does b-hCG do?
- maintains the corpus luteum during wks 3-6 pregnancy, thereby maintaining progesterone production, before luteal placental shift at wks 6-7 when progesterone production gradually shifts from the corpus luteum to the placenta
- promotes uterine angiogenesis
- promotes myometrial stability, preventing pre-labour contractions
- supports immune tolerance to growing embryo
When does b-hCG start to be mesurable?
In serum: 9 days post-conception
In urine: 28 days after 1st day of last menstrual period
What are the normal levels of b-hCG at different moments of the pregnancy?
plasma levels of b-hCG double every 48hrs from moment it is detectable up to about 8-10wks GA (peak at about 100 000), then falls during T2, then stays level but detectable throughout T3 until delivery
Basically:
10 at missed menses
100 000mIU/mL at peak at around 10wks GA
10 000 at term
How do we determine gestational age and estimated date of delivery?
- from 1st day of last menstrual period
- ultrasound
Lower levels of serum b-hCG may suggest…
- ectopic pregnancy
- miscarriage
- inacurrate dates
- normal
- trisomy 18 (Edwards syndrome)
- trisomy 13 (Patau syndrome)
Higher levels of b-hCG may suggest…
- multiple pregnancy
- molar pregnancy
- inacurrate dates
- trisomy 21 (Down syndrome)
- normal
- kidney disease (slower clearance)
By what is b-hCG produced?
primarily placental syncytiotrophoblast
also:
- nontrophoblastic malignant cells
- pituitary cells
- cytotrophoblast
