Gestational Pathology Flashcards
2 layers of the fetal membrane: The \_\_\_(A)\_\_\_ is a layer of \_\_\_(B)\_\_\_ epithelial cells affixed to a basement membrane that lines the inside of the amniotic sac, bathing in the amniotic fluid generated by the embryo or fetus.
The ___(C)___ is a variably thick connective tissue layer which abuts the decidualized endometrium of the uterus.
The umbilical cord normally contains two arteries and one vein embedded in a gelatinous yet firm matrix known as ___(D)___.
The umbilical vein carries oxygen and nutrients from the villi to the baby, then the deoxygenated blood from the baby goes back through the umbilical arteries to the ___(E)____.
a) amnion
b) cuboidal
c) chorion
d) Wharton’s jelly (WJ)
e) chorionic villi
Amniotic Fluid Infection -
What are the 2 ways this can cause a maternal inflammatory response?
What are the pathogens ass’d w/ each?
- Ascending infection (more common; bacterial)
- Group B streptococci
- Listeria monocytogenes
- (or multimicrobial) - Hematogenous spread (rare now; TORCH)
- Toxoplasmosis
- Others (Syphilis, Listeria, TB)
- Rubella
- Cytomegalovirus
- Herpes Simplex
What is Pre-eclampsia? Eclampsia?
Pre-eclampsia = Insidious onset of hypertension & edema, followed by proteinuria
Eclampsia = Seizures as a complication of pre-eclampsia
Maternal Hypertension occurs in 3-5% of pregnant women.
a) When during pregnancy does it typically occur?
b) It is more common in women w/ what characteristics? (4)
a) 3rd trimester
b) Primigravidas, women w/ molar pregnancy, hypertension, or pre-existing kidney disease
What are some complications of maternal hypertension?
Maternal:
- Seizures (eclampsia)
- Visual disturbances
- HELLP (Hemolysis, Elevated Liver enzymes, & Low Platelet count)
- ARF
Fetal:
- Pre-term labor
- IUGR
- IUFD
Maternal Hypertension - Tx/management?
Delivery ASAP
Estradiol is a mitogen for granulosa cells. What does this mean (“mitogen”)?
It means that it triggers granulosa cells to undergo mitosis & divide
3 pathologic features of Uteroplacental Insufficiency (placental ischemia)?
1- Small placenta
2- Placental infarcts
3- Decidual vasculopathy
Placenta Previa:
Where does the placenta implant?
What complication is ass’d w/ this?
Placenta implants on the lower uterine segment (LUS) or cervix.
Complication: Antepartum bleeding may lead to placenta accrete
(Further exp: The dilation of the cervix disrupts the placenta leading to antepartum bleeding. The bleeding may be mild, moderate or may be massive and life threatening hemorrhage)
What is a Placenta Accreta?
What complication is ass’d w/ this?
Placenta in direct contact to the myometrium
(i.e. no decidua in between)
Complication: Postpartum bleeding
Placenta Previa - how is Dx made?
Ultrasound
Where does the placenta normally implant?
Lateral wall of the uterine fundus
What is “Placenta Increta”?
When the chorionic villi penetrate through the myometrium
What is “Placenta Percreta”?
When the placental villi have perforated through the myometrium to or through the uterine serosa
(most severe abnormal placentation)
Placenta Accreta - Tx?
Hysterectomy
Complete molar pregnancy - Cause & Pathology? Risk of choriocarcinoma?
Some or all of the villi affected?
An egg that is missing its nucleus is fertilized and may or may not contain fetal tissue.
- Diploid (46 chromosomes – completely paternal)
- 90% is 46 XX “Daddy’s girl”
- No fetal parts on US
- Increased risk of choriocarcinoma
- All of the villi are affected
Partial molar pregnancy - Cause & Pathology? Risk of choriocarcinoma?
Some or all of the villi affected?
Cause - An egg that is missing its nucleus is fertilized by 2 sperm or by 1 sperm which reduplicates itself yielding the genotypes of 69,XXY (triploid) or 92,XXXY (tetraploid)
- Triploid (69 chromosomes – mixed paternal & maternal)
- 90% is 46 XX “Daddy’s girl”
- Fetal parts seen on US
- No increased risk of choriocarcinoma
- Some of the villi are affected?
How does a molar pregnancy typically present?
- Typically presents in the first or early second trimesters as abortion or with bleeding
- Very high hCG levels (»» normal pregnancy)
- Uterus bigger than a pregnancy of same gestational age
- Ultrasound shows “snowstorm”
appearance of uterus.
Gross & histologic appearance of molar pregnancy?
Gross appearance: “bunch of grapes” represents swollen chorionic villi
Histologic appearance: Swollen (edematous) villi, with circumferential trophoblastic proliferation
and nuclear atypia
The fetus gains 95% of its weight in the __?__ half of pregnancy.
2nd
Pregnancy Cardiac Ouput:
Half of increase occurs by __a__ weeks
Maximum cardiac output achieved by __b__ weeks.
a) 8
b) 20
**Changes anticipate increased demands not initiated by demands
T or F?
Heart rate increases 15-20 bpm during pregnancy.
True
Does Stroke volume change during pregnancy?
Yes, stroke volume increases 30%
What changes are seen during contractions of labor & then, immediately postpartum?
Cardiac output increases further during labor.
Immediately postpartum sudden increase in cardiac output.
What changes in the cardiac outline (as seen on x-ray) occur during pregnancy?
- Diaphragm elevated nearly 4 cm
- Apex of the heart pushed anteriorly and superiorly to the left
- Appears like cardiomegaly on chest x-ray
What changes are seen on the cardiac exam during pregnancy?
- Wide splitting of S1 is often present
- Splitting of S2
- Systolic ejection murmur
- Presence of 3rd heart sound
What changes that can be seen on echocardiogram occur during pregnancy?
- All four chambers and valvular annular diameters are increased.
- Mild pulmonic and tricuspid regurgitation present in 90%
- Mitral regurgitation in 30%
What EKG changes may occur during pregnancy?
- Ventricular extrasystoles are common
- Transient ST segment and T wave changes
- Presence of Q wave and inverted T waves in lead III
- Attenuated Q wave in lead AVF
- Inverted T waves in leads V1,V2,V3
Blood pressure changes during pregnancy?
- Decreased blood pressure mean 105/60
- Systolic decreased by 10 mm Hg
- Diastolic decreased by 15 mm Hg
- Returns to prepregnant levels at term
SVR changes during pregnancy?
SVR decreases during pregnancy
- High flow, low resistance of uteroplacental vascular bed and
- Systemic vasodilation
- Pregnant women refractory to angiotension II
Changes in antecubital and femoral venous blood pressure throughout normal pregnancy and early puerperium?
- Venous pressure in lower extremities is increased
- Along with decreased osmolality causes edema
Blood volume changes during pregnancy?
- Blood volume increases by 45%
- Protects against hemodynamic effects of blood loss
- Rise in plasma volume exceeds the increase in RBC mass
- Causes dilutional anemia hemoglobin 12g/dl
- Fetal requirement 6-7mg/day in 2nd half of pregnancy
Coagulation changes during pregnancy?
- Prothrombin and partial thromboplastin times decreased by 20%
- Resistance to activated protein C increases
- Protein S decreases
- Fibrinogen increases
- Hypercoagulable state
Immunological changes during pregnancy?
WBC increased –mostly neutrophils
Changes in lung volumes & respiratory rate during pregnancy?
Tidal volume increases 30-40%
- Mostly due to decrease in functional residual volume of 20%- residual volume decreases due to elevation of diaphragm
- Respiratory rate unchanged
Changes in ventilation & oxygen consumption during pregnancy?
- Minute ventilation rises by 50%
- Oxygen consumption increases by 20%
Changes in acid-base balance during pregnancy?
- Slight respiratory alkalosis with metabolic compensation
- Slight rise in Pa o2
Changes in urinary system during pregnancy?
- Renal hypertrophy increase in size by 1 cm
- Dilation of renal pelvis/calyces
(more on RIGHT than LEFT during 3rd trimester due to dextrorotation of the uterus) - Dilation of ureters to 2 cm
- Mechanical compression at the pelvic brim
- Progesterone-induced smooth muscle relaxation
Changes in renal blood flow & GFR during pregnancy?
Renal blood flow increases 50%
GFR increases 50%
Changes in serum BUN & Creatinine during pregnancy?
Glucosuria?
Proteinuria?
- Serum Creatinine and BUN levels decrease
- Glycosuria occurs due to exceeding of maximum tubular reabsorptive capacity
- No increase in proteinuria
Changes in Na & plasma osmolarity during pregnancy?
Na retention increases 900 mEq but serum Na decreases
- thus, ↓ plasma osmolality
Changes in glycemic control during pregnancy?
Large fluctuations occur
- Fasting glucose levels are lower—accelerated starvation
- Greater insulin secretion but higher glucose level in response to a meal
What causes the transient insulin resistance during pregnancy?
Insulin resistance due to placental hormones-human chorionic somatomammotropin, progesterone
- Also cortisol, prolactin and glucagon
Gestational Diabetes - etiology? Risk of T2 diabetes later on?
Gestational diabetes occurs when a woman’s pancreatic function not sufficient to overcome insulin resistance of pregnancy.
Half of women with GDM will develop Type 2 DM later in life.
Liver changes seen during pregnancy?
- Size and histology are unchanged
- Spider angiomas and palmar erythema due to high levels of estrogen
- Serum albumin and total protein decrease–dilutional
- Serum alkaline phosphatase is higher due to placental production
- Other LFT’s are unchanged
Gall Bladder changes seen during pregnancy?
- Decreased rate of emptying due to progesterone
- Cholesterol saturation is increased while chenodeoxycholic acid is decreased in bile favoring stone formation
GI changes seen during pregnancy?
Small bowel
- Motility is reduced due to progesterone allowing for more efficient absorption
Large bowel
- Decreased transit times allows for both water and sodium absorption
- Increased portal hypertension leading to dilation wherever there are portosystemic venous anastomoses
Skeletal changes seen during pregnancy?
- Lordosis of pregnancy~ progressive increase in anterior convexity of the lumbar spine Preserves center of gravity
- Ligaments of the symphysis and sacroiliac joints loosen during pregnancy due to relaxin
During pregnancy, increased _____ stimulates intestinal absorption
calcitriol
Skin changes seen during pregnancy?
- Hyperpigmentation
- 90% of pregnancies
- Localized to areas of increased melanocytes
- Infraumbilical skin darkens forming “linea nigra”
- Melasma or chloasma - mask of pregnancy
