Obstetrics

Question 1

Normal umbilical artery gas values

Answer 1

pH 7.28 (+- 0.05)
pCO2 49 +- 8.4
pO2 18.0 +- 6.2
HCO3 22.3 +- 2.5
Base deficit 4 +- 3

Question 2

Neonatal metabolic acidosis labs

Answer 2

pH <7.0, base deficit 12 or greater

Question 3

Effects of radiation exposure by gestational age

Answer 3

0-4w all or nothing
4-11w multi-organ systems
12-15w CNS

Question 4

Antiphospholipid syndrome diagnostic criteria

Answer 4

Meets one clinical and one lab criteria
Clinical:
- vascular thrombosis
- pregnancy morbidity (unexplained fetal death after 10w, preterm birth before 34w b/c of preE/eclampsia/placental insufficiency, 3+ consecutive SAB before 10w without other cause)
Lab: +Ab on 2 occasions 12+ weeks apart
- lupus AC, anticardiolipin med-high titer, anti-beta2 glycoprotein >99%ile)

Question 5

CMV in pregnancy

Answer 5

• most severe fetal effects in first trimester, but most commonly transmitted in third trimester (40-72% vs. 30%)
• up to 25% of babies with sequelae
• HSM, jaundice, petechiae, thrombocytopenia, hearing loss

Question 6

Congenital varicella US findings

Answer 6

Hydrops
Hyperechogenic foci in liver/bowel
Cardiac malformations
Limb deformities
Microcephaly
FGR
- most likely transmitted in 2nd tri, least likely in 3rd, overall unlikely (0.4-2%)

Question 7

TTTS Quintero staging

Answer 7

I: oli-poly (>8 and <2 cm in donor)
II: bladder absent in donor
III: abnormal dopplers (AEDF or reversal)
IV: hydrops
V: demise

Question 8

Diseases with highest risk of stillbirth

Answer 8

out of 1000 pregnancies
SLE (40-150)
Renal disease (15-200)
Cholestasis (12-30)
Prior stillbirth (9-20)
Late term pregnancy (14-40)
Multiple gestation (12-34)
FGR (10-47)
Diabetes (6-35), worse when on meds
Overall stillbirth rate 6.4/1000

Question 9

Di-di twin timing, diagnosis

Answer 9

Cleavage in days 1-3 (morula stage)
Can be mono or dizygotic
Twin peak/lambda sign

Question 10

Monochorionic timing, diagnosis

Answer 10

Cleavage in days 4-8 (dichorionic, blastocyst) or 8-13 (implanted blastocyst, monochorionic)
Thin dividing membrane (max 2mm)
Right angle between membrane and placenta
Fetal echo needed (risk of CHD)
Growth/fluid every 4 weeks
Antenatal testing at 32w
TTTS screening q2w starting at 16w

Question 11

Recommended weight gain in pregnancy

Answer 11

BMI <18.5 28-40
18.5-24.9 25-35
25-29.9 15-25
>30 11-20

Question 12

Obesity risks in pregnancy

Answer 12

Maternal: C-section, VTE, wound complications, endometritis, PPD, preE, GDM, OSA
Fetal: SAB, stillbirth, congenital anomalies (NTD, cardiac, orofacial/limb), indicated PTD, macrosomia, childhood morbidities (metabolic syndrome/obesity)

Question 13

Congenital rubella findings (US and postnatal)

Answer 13

US: cataracts, pulmonary a. stenosis, microcephaly, radiolucent bone disease
After birth: PDA, intellectual disabilities, sensorineural deafness

Question 14

Tetracycline fetal effects

Answer 14

Teeth staining

Question 15

Cerebral palsy imaging findings

Answer 15

Periventricular leukomalacia

Question 16

Erb palsy

Answer 16

C5-6
Waiters tip

Question 17

Klumpke palsy

Answer 17

C8-T11
Claw hand

Question 18

Congenital varicella findings

Answer 18

Skin scarring
Limb hypoplasia
Chorioretinitis
Microcephaly

High neonatal death rate when transmitted within 5d before to 48h after delivery

Question 19

Congenital CMV findings

Answer 19

Jaundice
Petechiae
Thrombocytopenia
HSM
FGR
Myocarditis
Nonimmune hydrops
Congenital hearing loss

30% of severely infected infants die, 65-80% of survivors have neurologic morbidity

Question 20

Parvovirus B19

Answer 20

aka Fifth disease
Fetus most vulnerable in second trimester
SAB, hydrops (aplastic anemia), stillbirth, FGR

Question 21

Toxoplasmosis

Answer 21

Transmission more likely in later gestation (10% first tri to 60% third tri)
Chorioretinitis, visual impairment, hearing loss, neurodevelopmental delay, HSM, ascites, periventricular calcifications, ventriculomegaly, seizures

Question 22

FRAX score

Answer 22

Used for patients with osteopenia or other high risk of fracture (T score -1.5 to -2.49)
10y risk major osteoporotic fracture 20% or greater, or hip fracture risk 3% or greater&raquo_space; treat

Question 23

Patients who do not require stress dose steroids

Answer 23

• Glucocorticoids <3 weeks (any dose)
• AM doses of prednisone <5mg/d (any length of time)
• <10mg of prednisone or its equivalent every other day

Regimen: hydrocortisone 25mg IV q6h, at delivery hydrocortisone 100mg IV
- taper to baseline regimen/3d

Question 24

Effects of isotretinoin

Answer 24

External ear malformations
Cleft palate
Micrognathia
Conotruncal heart defects/VSDs
Aortic arch malformations
Brain malformations

Question 25

Risk of neurologic injury and death with loss of one twin

Answer 25

Monochorionic: 18/15% Dichorionic: 1/3%

Question 26

Anthropoid pelvis associations

Answer 26

OP fetal position

Question 27

Platypelloid pelvis associations

Answer 27

Transverse arrest

Question 28

Risk of accreta with # prior C-sections, with/without previa

Answer 28

With previa: 1: 3% 2: 11% 3: 40% 4: 61% 5: 67% without previa (uptodate) 0.03> 0.2> 0.1> 0.8> 4.7%

Question 29

IUFD eval

Answer 29

CBC, syphilis, glucose/A1C, UDS, KB - offer karyotype/autopsy, amniocentesis/microarray

Question 30

Varicella US findings

Answer 30

FGR Limb hypoplasia Microcephaly Microphthalmia

Question 31

Toxoplasmosis US findings

Answer 31

Microcephaly Hydrocephalus Intracranial calcifications

Question 32

HSV US findings

Answer 32

FGR Microphthalmia Microcephaly Hydranencephaly HSM

Question 33

Rubella US findings

Answer 33

FGR Cardiac malformations (PDA, septal) Microphthalmia HSM

Question 34

CMV US findings

Answer 34

FGR Cerebral ventriculomegaly Microcephaly Hydrops Chorioretinitis Intracranial calcifications

Question 35

History indicated cerclage

Answer 35

- hx 1+ 2nd trimester loss due to painless cervical dilation (not labor or abruption) - prior cerclage due to painless dilation in 2nd trimester

Question 36

Exam-indicated cerclage

Answer 36

Painless cervical dilation in 2nd trimester

Question 37

Ultrasound-indicated cerclage

Answer 37

- Singleton - Prior spontaneous PTD <34 weeks - AND short cervix <25mm before 24w

Question 38

Most common benign neoplasm in pregnancy

Answer 38

Mature teratoma

Question 39

Most common malignant neoplasm in pregnancy

Answer 39

Dysgerminoma

Question 40

Vaginal progesterone indication

Answer 40

Incidentally found short cervix <20 mm No history of PTD <34w

Question 41

Criteria for failed induction

Answer 41

1. attempting induction for 24+ hours 2. Ruptured membranes 3. 12-18h of pitocin after ROM

Question 42

Down syndrome quad screen

Answer 42

elevated hCG, inhibin A Low AFP, estriol 16-18 weeks

Question 43

Contraction stress test

Answer 43

Satisfactory if: - at least 3 ctx in 10 mins - Each ctx 40s or more Negative: no late or variables Positive: lates after 50% or more of ctx (even if fewer than 3 in 10 mins) Equivocal if decels with contractions that are too frequent or last >90s

Question 44

ACE-I fetal exposure

Answer 44

Oligohydramnios Calvarium maldevelopment

Question 45

Danazol fetal effects

Answer 45

Androgenic/virilization of female fetus

Question 46

Isotretinoin fetal effects

Answer 46

Early pregnancy loss Cardiac abnormalities CNS anomalies

Question 47

Lithium fetal effects

Answer 47

Ebstein anomaly (apical displacement of tricuspid valve)

Question 48

Thalidomide fetal effects

Answer 48

Phocomelia (proximal aspect of extremity is absent)

Question 49

Rhogam coverage

Answer 49

300 mcg covers 30 mL of fetal whole blood or 15 mL fetal RBC - KB quantifies percent of fetal cells in maternal circulation, can be used to calculate # vials, assume 5L maternal blood - Give enough vials to cover, plus one additional vial for safety