CREOG REVIEW--OBSTETRICS
T. Lenzi 01/2005
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Definitions/Epidemiology
Perinatal period
Abortus
Includes all births weighing 500g – 28 days of life
Fetus less than 20 wks, weighing < 500g
Birth Rate
Stillbirth rate (fetal death rate)
Neonatal mortality rate
Number of live births/1,000 population
Number of stillbirths/1,000 infants born (LB+SB)
Number of neonatal deaths/1,000 live births
Low Birth Weight (LBW)
< 2,500g
Very Low Birth Weight (VLBW) <1,500g
Extremely Low Birth Weight
<1,000g
Maternal Mortality Ratio
Number of maternal deaths/100,000 Live Births
Direct maternal death
death as a result of obstetric complication
(ex: uterine rupture, DIC)
Indirect maternal death
Death NOT directly due to obstetrical cause
but resulting from pre-existing disease or disease
that developed during pregnancy which was
aggravated by the maternal physiologic adaptation
to pregnancy.
(ex complications of severe MS)
Nonmaternal death
Death resulting from accidental or incidental
causes (ex: CA, auto accident)
Type I (alpha error):
Type II (beta error):
false positive
false negative
Fetal Development
Zygote  Morula (solid)  Blastocyst
Implantation: Most common site: upper, POSTERIOR wall of uterus. Timing: 1 wk
Nagle’s rule for estimation of EDD: Add 7d to first day of LMP and subtract 3 mos
Fetal heart begins to beat at 3 weeks
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Genetics
MOST DISEASES ARE MULTIFACTORIAL (multiple genes controlling, recurrence
risk: 1-5%)
Examples of Autosomal Dominant Diseases (50% risk of transmission)
Achondroplasia, Huntington’s, MYOTONIC DYSTROPHY, Marfan’s,
Neurofibromatosis, vonWillebrand’s
Examples of Autosomal Recessive Diseases (25% recurrence risk)
CF, Sickle Cell, Tay Sachs, alpha thal, CAH (almost ANY enzyme defect)
Examples of X-Linked Recessive (usually found in males)
G6PD, color-blindness, DUCHENNE/BECKER MUSCULAR DYSTROPHY
Chromosomal disorders present in >50% of first trimester sAbs. MOST COMMON
GROUP: TRISOMIES (T16), MOST COMMON ANEUPLOIDY: monosomy X
(Turner).
Recurrence risk in pt with prior aneuploidy: 1%.
Chromosomal disorder NOT associated with increasing maternal age: Monosomy X
(Turner Syndrome)
Lyon hypothesis: X chromosome inactivation (in pt with 47XXX, 2 chromosomes
inactivated)
Advanced paternal age (45yo): increased AUTOSOMAL DOMINANT mutations
Cri-Du Chat: deletion of 5p
Most common cause of mental retardation in males: Fragile X (Testing: look for triplet
repeats in X chrom)
Dx of B Thal on Hb Electrophoresis: Increased HbA2 and HbF
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Quadruple Screen analytes:
AFP site of production: Fetal Liver, Most common reason for abnl AFP: wrong GA
HCG
Estriol
Inhibin
DS: Decreased AFP, (sometimes increased HCG, decreased E3)
NTD: Increased AFP
T18: All analytes LOW
Prenatal Diagnosis/Ultrasound
First Trimester Screening—Same sensitivity with lower false + rate than QS
Fetus measuring 45-84 mm (appx11-13+6 wks)
Midsaggital section with nasal bone
Measurement of Nuchal translucency + serum PAPP-A and Free B HCG
Normal NT measurement appx 1-2 mm (nl 2nd tri nuchal thickness: 5mm)
>= 3mm is ABNORMAL and associated with CARDIAC DEFECTS
Fruits in Ultrasound:
Banana sign
Lemon sign
Strawberry Head
abnl curvature of cerebellum in NTDs
calviarium depression in NTDs
abnl head shape in T18
Other Ultrasound Facts
Most common congenital defect: cardiac, next most common: NTD.
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TV u/s can detect gestational sac at a BHCG of 1500
Most common cause of SGA infant: constitutional
MOST ACCURATE single measure of gestational age: BPD.
Safest method of pregnancy termination between 14-20 weeks: D+E
Double bubble= duodenal atresia, associated with DS. May not be picked up until
24+ weeks (with increased fetal swallowing).
Cystic hygroma most commonly associated with Turner Syndrome (Monosomy X)
Most common diagnosis in male fetus with hydronephrosis, dilated bladder: posterior
urethral valves
Most common cause of ambiguous genitalia in a newborn: Congenital Adrenal
Hyperplasia (CAH)
Causes of NTDs: folic acid deficiency, heat, irradiation, alcohol, valproic acid,
carbamezipine, aminopterin. Recurrence risk: 2-3% (higher for anencephaly)
Holoprosencephaly found most commonly in: T13. Common associated defects: cleft lip
and palate, other facial abnormalities.
Most likely complication of sacrococcygeal teratoma: HYDROPS (the tumor may act as
a shunt). Usually these tumors are NOT malignant in the fetal period (but become
malignant after birth).
Most common cause of echogenic kidneys: ARPCKD (autosomal recessive polycystic
kidney disease). Associated with oligo and pulmonary hypoplasia. May also see hepatic
fibrosis.
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T21
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T18: IUGR, cardiac defects, overlapping 4th/5th digits
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Gastroschisis
Usually on right of umbilicus
Dx: nl cord insertion
Usually isolated
Small bowel only
Usually HIGH AFP
Bowel may appear thick (chem. Peritonitis)
Amnio not indicated
Omphalocele
Midline
Dx: cord insertion is part of lesion
Often assoc with other anomalies
May contain liver, other abd organs
AFP may be normal
No peritonitis (covered by SAC)
Offer amnio
Echogenic bowel:
Associated with T21, CF (meconium ileus), CMV, swallowed
blood, meconium peritonitis
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Arnold Chiari Malformation:
Ventriculomegaly, + lemon or banana sign, +
obliteration of the cisterna magna. Seen in NTDs.
Dandy-Walker Malformation
Large cisterna magna, defect in cerebellar
Vermis +/- ventriculomegaly
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Drugs and Teratogens
Pre-Implantation Period
Embryonic Period
Fetal Period
Fertilization – 2 wks, ALL OR NONE
wks 2-8, ORGANOGENESIS
wks 9-term (brain still susceptible)
Alcohol
Hypoplastic philtrum/lip, flat nasal bridge, epicanthal folds
ACE inhibitors
Renal tubular dysgenesis oligo  pulmonary hypoplasia
+ contractures, hypoplasia of calvarium
Aminoglycosides
fetal cranial nerve VIII damage
Anticonvulsants:
Hydantoin, Carbamezepine (Tegretol), Phenobarb  metabolized by epoxide hydrolase,
may cause fetal hydantoin syndrome: IUGR, MR, facial abnormalities, nail hypoplasia.
Associated with hemolytic dz of newborn tx newborn with parenteral vit K.
Valproic acid (Depakote)
NTDs
Chloramphenicol
Gray baby syndrome
Cocaine
Placental abruption, brain defects, limb reduction defects
(mostly as a result of hemorrhages)
DES
Last used: 1971, cx/uterine anomalies, clear cell CA vagina
Li
Ebstein’s anomaly (tricuspid atresia)
Methimazole
aplasia cutis (scalp abnormality), controversial
Nitrofurantoin
Hemolytic anemia in women with G6PD deficiency
Quinolones
fetal arthropathy
Sodium Nitroprusside
feto-toxic concentrations of metabolites
Sulfas
Hyperbili in infant if used near delivery
Tetracycline
Tooth discoloration
Thiazides
Neonatal thrombocytopenia
Warfarin
nasal hypoplasia, ephiphyseal stippling, IUGR, NTDs
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Fevers/Heat
Neural tube defects
Radiation:
Acceptable limit: 5 rads, mental retardation associated with
doses of >= 20 rads. CXR= 0.05 milli rad, First trimester exposure: all or none (abort or
no effects). Procedures with highest acceptable exposures: BE/small bowel series.
CONTRAINDICATED: RADIOACTIVE IODINE (fetal thyroid begins concentrating
Iodine at 10 wks)
Retinoids
ear abnormalities (microtia), stenosis of ext ear
Hint: facial lesions most likely to result from ETOH, Dilantin or Warfarin
Placental Physiology
Amnion and chorion fuse at appx 14 wks.
Primary source of Progesterone: MATERNAL LDL
Primary source of Estrogen: FETAL ADRENAL (16-OH-DHEAS—Remember, the
quadruple screen measures estrogen, which comes from the fetus)
Placental type: HEMOCHORIOENDOTHELIAL (only other mammal with this type of
placentation is the guinea pig).
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HCG structurally related to TSH, FSH, LH- they share ALPHA subunits. The beta
subunits are distinct (measure B HCG). Some forms of HCG can stimulate TSH receptor
(thyroid symptoms with molar pregnancies).
HCG “rescues” the corpus luteum. Corpus luteum produces Progesterone for first 6-7
weeks.
Diabetogenic hormone of pregnancy : Human Placental Lactogen (HPL)
Placenta Previa: Risk factors: AMA, increasing parity, prior uterine surgery, smoking.
Nitabuch layer of fibrinoid degeneration absent in placenta ACCRETA
Placental abnormality associated with IUGR: CIRCUMVALLATE placenta
Diseases associated with placentomegaly: syphilis, isoimmunization/hydrops, DM
Placental Sulfatase Deficiency: X-linked. Decreased Estrogen, associated with
prolonged gestation and icthyosis in affected males.
Placental Aromatase Deficiency: (aromatase converts androstenedione to estrogen).
May lead to VIRILIZATION of mother and female fetus.
Vascular placental mass= chorangioma. May function as AV shunt and cause
HYDROPS- follow serial fetal ultrasounds.
Maternal Physiology
Pulmonary Function in Pregnancy
Tidal Volume
Vital Capacity
Minute Ventilation
pH
Increased
Increased
Increased
Increased (mild alkalosis)
Resp rate
Unchanged
PCO2
Expiratory Reserve volume
Residual Volume
Functional Residual Capacity
Decreased (blow off CO2)
Decreased
Decreased
Decreased
Cardiovascular Changes:
Increased intravascular volume
Increased HR/CO
Decreased SVR (BP)
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
Diastolic heart murmurs are ALWAYS abnl in pregnancy
Amniotic Fluid Dynamics
AF volume maximum at: 36-38 wks (appx 1 L)
Maternal Nutrition
Folic acid doses: 0.4 mg (or 400 mcg) in general population
4.0 mg in patients with h/o NTD or those on antiepileptic drugs
Increased caloric need for pregnancy: 300 Kcal (500 Kcal for breastfeeding)
Total Iron requirements for pregnancy: 800-1,000mg (50% to mom, 30% to fetus, 20%
normal female requirement)
Iron interferes with thyroid replacement (synthroid)- separate doses by 4-6h
Fetal Physiology
There are 3 shunts in the fetus that allow oxygenated blood to travel preferentially
to the brain.
Path of fetal RBC: Oxygenated blood from placenta travels in umbilical VEIN
thru DUCTUS VENOSUS to IVC to Right Atrium, through FORAMEN OVALE to Left
Atrium then Left Ventricle to Aorta, then through DUCTUS ARTERIOSUS, where
oxygenated blood flows preferentially to coronary arteries to perfuse heart and to the
brain. The lungs do not receive the bulk of the oxygenated blood from mom.
Deoxygenated blood travels in the SVC and IVC and is preferentially shunted to
the right atrium then RV then to the pulmonary circulation.
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Fetal Lung Development
Blood may interfere with L/S ratio but not PG (phosphatidlyglycerol) testing (ie can
collect vaginal pool for PG, but not L/S).
Surfactant is produced by Type II pneumocytes
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Multiple Gestation
Most common type of conjoined twins: thoracophagus
Zygosity:
70%
DIZYGOTIC (DZ) (Dizygotic twins are ALWAYS Di/Di, but
may have fused placentas)
30%
MONOZYGOTIC (MZ)
(2/3 Di/Mo, 1/3 Di/Di)
Of Di/Di twins, Most (90%) are Dizygotic, 10% are monozygotic
Most common presentation of twins: vtx/vtx
Interlocking Twins: Breech/Vertex (think: interlocking chins)
Vanishing twin: 20% of twin pregnancies (may see fetus papyraceus at delivery)
Calculation of discordance: Difference in weights/ EFW of larger twin
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TTTS:
-25% of Di/Mo pregnancies (severe in 15%)
-due to ARTERIO-VENOUS anastomosis (donor pumps arterial blood to cotyledon
drained by recipient VEIN).
Dx
-Monochorionic placentation
-Poly-Oligo sequence
-Discordance >20%
-Non-visualization of donor bladder, large, recipient bladder
TRAP sequence:
Twin Reversed Arterial Perfusion Sequence, associated with
ACARDIAC TWIN. Due to paired artery to artery and vein to vein anastomoses.
Hemolytic Disorder of the Newborn
D antigen present as early as 5 weeks in fetus
Two most common causes of isoimmunization: Anti D, anti Kell
Common antibodies: Kell Kills, Kidd Kills, Duffy Dies, Lewis Lives (it is IgM)
Liley Curve: Measures optical density of AF in cases of isoimmunization due to
hemolytic anemia (bilirubin in AF). Deliver or do IUT if UPPER ZONE II or ZONE III.
In which two causes of anemia is it not possible to follow amnios for Delta )D 450:
Parvo, Kell (these cause ERTYHROBLASTIC NOT HEMOLYTIC ANEMIA, therefore
amniotic fluid bilirubin is NOT elevated)
Rhogam (300 mcg dose) protects against 30 ml of fetal blood or 15 ml of fetal RBCs.
Most common cause of RhD isoimmunization: prior term delivery
Term delivery without rhogam tx
20% risk isoimmunization
Rhogam at delivery only
2% risk isoimmunization
Rhogam at 28 weeks and PP
0.2% risk isoimmunization
Apt test: differentiates fetal blood from maternal blood in the evaluation of bloody
stools. To perform: add base to sample. Fetal cells remain pink, adult cells lyse (turn
brown- less resistant).
Shilling test= vitamin B12 absorption test
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Platelet Disorders:
Gestational Thrombocytopenia:
PLT > 70,000, no symptoms, no tx
ITP: PLT < 100, nl bone marrow megakaryocytes, absence of splenomegaly. Most
have h/o bruising. Maternal anti-PLT IgG can cross placenta and cause bleeding in
neonate. Tx :steroids.
Neonatal Alloimmune Thrombocytopenia (NAIT): Decreased FETAL PLATELETS.
Presents with neonatal hemorrhage. Platelet equivalent of Rh disease, although unlike Rh
disease, NAIT may present with the first child. Tx: IvIg.
Preterm Labor
Most significant risk factor for PTD= PRIOR PTD
AVOID TOCOLYTICS in pts with PYELO—RISK OF PULMONARY EDEMA
Proven efficacy of tocolytics: delay delivery by a few days (allowing administration of
steroids)
Mechanism of Tocolytics:
Terbutaline: increases intracellular cAMP  inhibits myosin light-chain kinase
Mg
decreases Ach release at motor end plate, increases cAMP, decreases Ca
Indocin
inhibit cyclooxygenase and decrease synthesis of prostaglandins
CCBs
inhibits influx of calcium through cell membrane
Medical contraindication to Mg: myasthenia gravis
Treatment of Mg toxicity: calcium gluconate
Contraindications to tocolysis
Severe bleeding
Severe preeclampsia
Chorio
Fetal death or fetal anomaly inconsistent with life
Severe IUGR
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Trick question: Is asthma a contraindication to B mimetics?
NO- B mimetics are a tx for asthma. Asthma is however a contraindication to
prostaglandins.
Maternal and Fetal Infectious Disorders
Tx of community-acquired PNA: erythromycin
Most sensitive indicator of Amniotic infection: IL-6
Rash/pruritis around nipples line and belt line: Scabies, tx in pregnancy: topical
antiparasitic (lindane).
Varicella- maternal varicella PNA has high mortality rates. Newborn transmission:
Treat neonate with VZIG if maternal infection manifests 5 days before or 2 days after
delivery (because mom has not yet produced IgG to give passive immunization to baby).
Fetal risk of malformations: 2% if infected prior to 20 wks, rarely after 20 wks.
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Most common organism in SEPTIC SHOCK: E COLI
What bug does Amp and Gent miss: enterococcus.
Vaccines in Pregnancy:
Acceptable: Hep B, Influenza, Tetanus/Diptheria
Contraindicated: LIVE VACCINES: MVP: MEASLES, mumps, rubella,
Varicella, Polio, BCG
HIV in Pregnancy
AIDS: Diagnosis
•
•
•
•
•
•
•
Opportunistic infection:
Neoplasia (including advanced cervical CA)
TB
Recurrent pneumonia
Dementia/Encephalopathy
Wasting syndrome
CD4 <200 (nl: 800-1200)
Correlates of Increased Perinatal Transmission of HIV
Advanced disease (AIDS-defining conditions, low CD4 counts, p24 antigenemia
Increased viral loads)
Placental inflammation
STDs
Duration of rupture of membranes
Delivery Plan in HIV+ Pts
C/S at 38 weeks when viral load > 1,000
Start iv AZT 3h prior to scheduled c/s
If NSVD planned, avoid AROM, instrumentation, episiotomy
Breastfeeding NOT recommended
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Hepatitis C
Indications for testing: IVDU (even ONCE!)
Recipeints of blood or organs prior to 1992
Hemodialysis pts
Elevated LFTs
Testing for HCV
EIA (enzyme immunoassays), many false +, confirm with RIBA
*In pt with ACUTE illness: HCV PCR (antibody response delayed)
Risk of perinatal transmission with HCV: 5%
Syphillis: Pts with +RPR  confirm with specific test (ex FTA). Tx= PCN (if allergic,
desensitize). In tx of secondary syphilis, monitor pregnant pts for Jarisch-Herxheimer
rx (fever, chills, hypotension, worsening of lesions, PTL, abnl FHTs)
Parvo: (“slapped cheek” disease, 5ths disease, erythema infectiousum). If + IgM, serial
ultrasounds for 2-3 months after maternal infx- 30% of fetuses become infected, but only
3% severely affected with aplastic anemia.
PPD+
15 mm in pts with no risk factors, 10mm in pts with risk factors, 5mm if
HIV or otherwise immunocompromised.
If PPD +  CXR
CXR Negative: INH/ B6 x 6 mos if <= age 35
CXR Positive  Check sputum for AFB
AFB+  3 drug therapy
Diabetics with signs of sepsis, DECREASED SENSATION OF SKIN: THINK
NECROTIZING FASCIITIS.
Hypertension in Pregnancy
MAP = systolic BP + 2 DBP
3
MAP non-pregnant: 87, pregnant: 90
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Diabetes in Pregnancy
Most common neonatal metabolic abnormality: hypocalcemia
Most appropriate test during postpartum period to evaluate a GDM: 75g 2h OGTT
Most common fetal abnormality: cardiac defects, most specific abnormality found in
DM: caudal regression.
Tx of DKA: IVF and INSULIN
Medical Disease in Pregnancy
Autoimmune disorders associated with neonatal disease: Graves, Myesthenia Gravis,
ITP, SLE
Fetal heart block associated with SSA, SSB (found in SLE and Sjogrens).
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Tx fetal SVT: digoxin.
Myesthenia gravis: dx: edrophonium test. MG IS CONTRAINDICATED.
Must have 1 clinical and 1 laboratory criterion.
Remember ONY ACL IgG counts for diagnosis.
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Depression in Pregnancy and Postpartum
Most common risk factor: prior history of depression
Tx: SSRIs
Obstetric Emergencies:
Definition of PPH: >500cc blood
Fastest way to rule out DIC in presence of life-threatening bleeding (observation of blood
clotting).
Best sign of adequate fluid replacement: urine output.
Tx of depressed infant when mother received morphine: naloxone
Dx AFLP: increased LFTs, HYPOGLYCEMIA, increased ammonia, fatty infiltration on
bx (Genetic testing: test baby for L-CHAD deficiency).
Tx of uterine inversion: Terb or halothane (practically speaking: nitrous). Most common
placental implantation with inversion: FUNDAL.
Sudden onset of bleeding, respiratory and/or cardiac collapse immediately after delivery:
think Amniotic Fluid Embolus (AFE)
Post partum pt with fatigue and EDEMA: think peripartum cardiomyopathy.
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Most common cause of seizure during repair of 4th degree laceration: seizure from
lidocaine toxicity.
Courvelaire uterus: infiltration of blood through myometrium and serosa (usually as a
result of massive abruption).
Woman with diffuculty producing milk and h/o PPH (or hypothyroidism, loss of
pubic/axillary hair): think SHEEHAN SYNDROME (anterior pituitary-NOT
hypothalamic necrosis after PPH)
Pt with thrombocytopenia, fever, renal dysfunction: TTP (Pentad: thrombocytopenia,
fever, coombs negative hemolytic anemia, renal dysfunction, fluctuating neurologic
dysfunction). Tx: PLASMA EXCHANGE.
Tx of Thyroid Storm: PTU, LITHIUM, DEXAMETHASONE, PROPANOLOL.
Monitoring pt with IUFD: Fibrinogen
Parturition
The pelvic plane which cannot be DIRECTLY measured: OBSTETRIC CONJUGATE
Frequencies of presentations at term: 95% vtx, 3% breech
Face presentations: can deliver vaginally if MENTUM ANTERIOR (in mentum
posterior presentations, brow is compressed against symphysis, and fetal head cannot
flex)
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Engagement= BPD (greatest diameter of fetal head) passes through pelvic inlet (0 station)
Pelvis Types:
Associated with OP presentations: Anthropoid
Associated with deep transverse arrest: Platypelloid
Associated with difficult vaginal deliveries: android
Most Caucasian women are gynecoid, many African-American women are anthropoid.
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Indication for low vertical (Kronig) incision: planned C-hyst (to avoid extension of
incision into broad ligament), extreme preterm infant (poorly developed LUS).
Indications for classical incision: Transverse lie BACK DOWN, lower segment myoma,
higher order multiple gestation, fetal anomalies (sacrococcygeal teratoma, severe
hydrocephalus).
Other name for low transverse incision: Kerr
Adverse effects of oxytocin: hypotension (water intoxication with high doses)
Contraindications to Epidural: Aortic Stenosis
Contraindication to prostaglandins: Asthma
Contraction pain: T11-L1
Perineal pain: S2-S4
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Simpsons:
NON-overlapping shanks. Good for molded heads. True Simpsons are
fenestrated, which is better for increased traction (for mid-forceps deliveries)
Eliots have OVERLAPPING shanks, less maternal tearing.
Tucker-McLanes are modified Eliots
Kielland forceps have a cephalic curve but NOT a pelvic curve- good for rotations. The
sliding lock is used for correction of asynclitism.
Pipers are used for the aftercoming head in a breech delivery.
Cancer in Pregnancy
Malignancy MOST likely to metastasize to fetus/placenta: melanoma
Puerperium
Most common cause of PPH: uterine atony
Luteoma = SOLID ovarian mass, will regress after pregnancy
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Lactation
Contraindications to breastfeeding: HIV (NOT contraindicated: Hep B, Hep C more
controversial, but OK esp if low viral loads)
Exclusively breastfed infants at risk for: Iron-deficiency anemia
Most common organism in mastitis: coag + staphylococcus aureus
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Misc
Foot drop after NSVD caused by peroneal nerve injury
+
b
a
c
d
Sensitivity:
a
a +c
PPV:
a
a+b
NPV:
d
c+d
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Prevalence
Age group
Perinatal
Transmission
Hepatitis B
1.25 million Americans infected
20-49
Chronic infx, prior to tx:
Hep BsAg
10-20%
Hep BsAg +Hep BeAb
90%
HBIG + vaccine 85-95% effective
Acute infx:
1st trimester
10%
3rd trimester
80-90%
Amniocentesis
Breastfeeding
Test neonate for HepBsAg, HepBsAb
and Hep C Ab at 12 mos
OK
Fine in immunized children
If HepBsAg+: 10-20%
Risk of
contracting
after needlestick
Risk of contacts Household contacts: not uncommon
getting infected
Sexual contacts: 25% infected
Acute: Both HbcIgM and HepBsAg
Testing
Core IgM increases 2-8 wks prior to
sx’s
Acute Infx
30% asymptomatic
Course
89-90% Resolve
10-15% Chronically infected
Tx
*MOST newborns will NOT clear the
infx
4 approved drugs including IFN
Hepatitis C
3.9 million (1.8%) Americans infected
30-49
Hepatitis C alone: 5-6%
Hep C + HIV
14%
Test neonate at 12 mos (maternal Ab to
HCV can persist.
?
Per ACOG: 2-3% risk transmission, per
CDC: No increased risk
HCV+: 1.8%
Household contacts: ? probably not
common
Sexual Contacts: 1.5% amongst spouses
HCV Ab (EIA + confirmatory),
however, for ACUTE: HCV Ab may be
negative (takes 5-6 wks to appear): do
HCV QUALITATIVE PCR within 1-2
wks of infx
Many asymptomatic and remain
undiagnosed
15-25% Resolve
75-85% Chronically infected
Of chronically infected, 10-20%
develop cirrhosis, 1-5% develop HCC
IFN alone OR IFN+Ribavarin
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