MFM Flashcards
Ace inhibitors
Renal dysplasia
Amniocentesis
Greater than 15 weeks gestation
Fetal loss <1/500
Tests amniotic fluid skin cells
Amniotic band syndrome
Constriction or amputation of digits/limbs
31% associated with club foot deformity (20% bilateral)
Antenatal steroids decrease risk of ___
RDS
NEC
IVH
Neonatal death
Biophysical profile (BPP)
In a 30 minute window
- breathing for >30 seconds
- > 3 movements of torso/limbs
- > 1 flex and extend
- > 2 cm fluid pocket
Blood volume in pregnancy increases by?
45%
Max volume at 32 weeks
Placental carbon dioxide transport
Very lipid soluble, rapidly transported
Category I FHR
Baseline 110 to 160
Moderate variability
No late or variable decels
Category II FHR
Everything not category I or III
Category III FHR
Absent variability and either:
Recurrent late or variable decels
Bradycardia
Causes of hydrops fetalis
Anemia (parvovirus, FMH, TTTS)
Cardiac failure (elevated RA pressure)
Decreased osmotic pressure (syphilis, CMV)
Impaired lymphatic drainage (cystic hygroma, chromosomal anomalies)
Cell free DNA
After 10 weeks
Detects fetal DNA in maternal serum
Very accurate for T21, T18, T13
Chorionic villus sampling
11 to 13 weeks gestation
Fetal loss 1/200-300
Circumvallate placenta
Membranes are on opposite side of placenta
Painless bleeding in 1/2 cases
Risk of death or neurologic injury with twin demise
20% (MC) vs 1% (DC)
More likely if triplets vs twins
Immediate delivery will not help, the cause is hypotension

DES
Vaginal adenocarcinoma and adenosis
Diffusion calculation
Rate of diffusion = Permeability x Surface area x Concentration difference (Cm-Cf)
Estimated fetal weight
Within 15% of actual weight 95% of the time
Less accurate at higher gestational ages
HCG
TSH like effects (alpha subunit the same)
Causes nausea and vomiting in pregnancy
Human chorionic somatomammotropin (HCS)
Previously known as human placental lactogen (HPL)
Anti-insulin affects (GDM)
Stimulates fetal somatic growth
Hemochorial placenta
Humans
Maternal blood in direct contact with trophoblastic tissue
More permeable to lipid soluble molecules
Hemodynamic changes in pregnancy
Cardiac output increases by 43% (HR and SV)
SVR decreases by 21%
Colloid pressure decreases by 14%
Causes of high maternal AFP
Open NTD Twins Fetal maternal hemorrhage Abdominal wall defects Lowe Syndrome Congenital nephrotic syndrome Fetal death If unexplained, increased risk of growth restriction or death of fetus
IGG transfer
Via endocytosis
Uses a vesicle to protect from proteolysis
IGM transfer
No passage across placenta
Intervillous space
Confined space
Increased blood goes across villi to fetus
Late decelerations
Occur after every contraction
Caused by utero placental insufficiency
Latency antibiotics
Broad-spectrum abx x 7-10 days
Reduces risk of RDS, NEC, neonatal/maternal infxn
Lipid insoluble molecules
Unless a transporter present - cross through paratrophoblastic routes
Size dependent, small pathways, low permeability
Lipid soluble molecules
Diffuse across entire trophoblast surface
Permeability is large
Dependent on concentration gradient
Lithium
Ebstein’s anomaly
What causes maternal serum estrogen to be low?
Placental sulfatase deficiency
Anencephaly
CAH
Molar pregnancy
Maternal oxygen administration
Increases O2 carrying capacity in the mother
Leads to a larger increase in fetal oxygen content
Maternal thyroid in pregnancy
TBG increased
Total T4 increased
Early pregnancy HCG mimics TSH, so TSH levels are low and free T4 levels are high
MCA Doppler
Best non-invasive test to assess for fetal anemia
Methotrexate
FGR
Developmental delay
Non-stress test (NST)
Reactive = 2 or more accelerations in a 20 minute window
HR increase by 15 BPM for at least 15 seconds
MCC of non-reactive NST is fetal sleep
NSAIDs in pregnancy
Oligohydramnios
Narrowing or closure of PA in utero (PPHN after delivery)
Oligohydramnios
Single verticle pocket (SVP) <2 cm
AFI <5 cm
SVP is better predictor
Placental oxygen transport
Determined by oxyhemoglobin disassociation curve
Fetal temp higher, more acidotic, fetal Hgb
Phenytoin
FGR
Microcephaly
Midface hypoplasia
Hypertelorism
Placenta Accreta
Leads to massive maternal hemorrhage
- Accreta invades the endometrium
- Increta invades the myometrium
- Percreta goes through the myometrium, can involve the bladder
Amino acid transport
Active transport, requires energy
Fetal concentration greater than maternal
Carbohydrate transport
Facilitated diffusion, no energy required
Requires GLUT receptors
Follows a concentration gradient
Placenta consumes glucose to maintain gradient
Placenta previa
Placenta covering the cervical os
Leads to maternal hemorrhage and preterm labor
Three types: marginal, complete, low lying
Placental abruption
Placenta breaks away from endometrium
Most of blood loss is maternal blood (intervillous space)
Clinical diagnosis - painful bleeding
Calcium transport in pregnancy
Facilitated diffusion from mother to placenta
Protein binding in placenta to maintain concentration gradient
Active transport from placenta to fetus
Potassium transport in pregnancy
Tightly regulated through K pumps
Fetal levels greater than maternal levels
Lipid transport in pregnancy
Dependent on trans placental concentration gradient
Sodium transport in pregnancy
Simple diffusion across a concentration gradient
Similar levels in mother and fetus
Vitamin transport In pregnancy
Fat soluble: simple diffusion, deficiencies rare, toxicity possible
Water soluble: active transport
Iron: active transport using transferrin
Polyhydramnios
SVP >8 cm
AFI > 25 cm
AFI better predictor
RBCs in pregnancy
20-30% increase Dilutional anemia (blood volume increases by 45%)
Respiratory changes in pregnancy
Tidal volume increases by 35%
Minute ventilation increases by 40%
FRC decreases by 20% (uterus pushes up diaphragm)
SSRIs during pregnancy
Neonatal adaptation syndrome
Pulmonary hypertension
Succenturate lobe
Accessory lobe of the placenta
Blood vessels exposed and may rupture during labor
Set up for vasa previa
Timing of twin separation
Di-di: days 1-3
Mono-di: days 4-7
Mono-mono: days 8-12
Conjoined: days 13-15
Transtrophoblastic channels
Very small (20 nm) Carry water soluble molecules Channels can dilate and close (mechanism for water balance)
EBM treatments for preterm birth
Antenatal corticosteroids
Transfer to tertiary center before delivery
Administration of antibiotics for GBS
Magnesium for neuroprotection
Twin twin transfusion syndrome (TTTS)
Both twins can develop hydrops
Recipient twin: increased blood volume, potential for heart failure, polycythemia, polyhydramnios
Donor twin: poor growth, oligohydramnios, anemia
Umbilical artery Doppler
Helps manage fetal growth restriction
Absent or reversed diastolic flow means high risk of morbidity and mortality
Valproic acid
NTD
Developmental delay
Variable decelerations
Variable relationship to contractions
Caused by umbilical cord compression
Vasa previa
Fetal vessels exposed in front of cervix
At risk for tearing during the labor process, leading to fetal exsanguination
Velamentous insertion
Vessels are freely on the placental surface
Increased risk for:
- growth restriction
- preterm birth
- fetal bleeding during labor (fetal mortality rate is 75%)
Warfarin
Midface hypoplasia
FGR
Microcephaly
What kind of blood flow does human placenta have?
Concurrent flow between maternal and fetal blood
Do not cross the placenta
TSH Biliverdin Heparin Insulin Glucagon Growth hormone IgM Complement
Quad screen T21
Low AFP
Low E3
High HCG
High inhibin
What is a category 1 FHR predict?
Normal fetal acid base balance
Carbamazepine during pregnancy
Growth restriction
Finger nail hypoplasia
Craniofacial defects
Neural tube defects
What crosses the placenta via simple diffusion?
Respiratory gases
Lipids
Fat-soluble vitamins
Sodium
What crosses the placenta via facilitated diffusion?
Glucose
Some glucocorticoids
What crosses the placenta via channels?
Water
Some ions
What crosses the placenta via active transport?
Amino acids
Proteins
Potassium
What crosses the placenta via receptor mediated endocytosis?
Immunoglobulin G
LDLs
Iron
What creatinine level is a relative contraindication to pregnancy?
> 2.5
What is associated with amnion nodosum?
Anything associated with oligohydramnios
