SCREENING AND MANAGEMENT ISSUES IN OBSTETRICS
| HOW TO MANAGE PSEUDO- AND QUASI-ABNORMALITIES ON ULTRASONOGRAPHY— Mary E. Norton, MD,
Professor of Clinical Obstetrics and Gynecology and Director, Division of Perinatal Medicine and Genetics, University of
California, San Francisco, School of Medicine
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| Prenatal ultrasonography (US): 3% to 4% of women deliver infants with major birth defect or congenital anomaly;
of those, ≈50% realistically diagnosable by US; of those diagnosable, 15% to 30% detected; “soft” markers (ie, pseudoabnormalities)
present in 10% to 15% of all US (more common than true abnormalities); issue of whether doing more
harm than good by using US to look for birth defects in fetus
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| Risks of US: no teratogenic risk; risk of creating anxiety related to false-positive diagnosis, prompting unnecessary interventions;
conversely, high-risk women falsely reassured by inaccurate US; can dissuade high-risk women from having
diagnostic procedures if relying on screening US (not nearly as sensitive)
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| Findings with no pathologic significance but possible markers for abnormalities
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 | Choroid plexus cysts (CPCs): found in brain of fetus; fairly common; resolve in essentially all cases, regardless of whether
chromosome abnormality present; marginal association with trisomy 18; vary in size and number; unilateral or bilateral;
slightly higher risk if large and bilateral; meta-analysis of 8 trials over 10-yr period in women <35 yr of age (low risk;
>100,000 patients); 1% of fetuses had isolated CPC (no other abnormalities detected by US, and triple screen value normal);
none had trisomy 18 in absence of other risk factors; important to ascertain whether no other structural abnormalities;
speaker confident level I US at her facility provides complete evaluation of fetal anatomy; if patient referred and
physician unsure of comprehensiveness of original US, perform level II US and correlate results with patient’s triple
screen; if normal, reassure patient that finding normal variant; follow-up with US of no benefit; amniocentesis not recommended
in absence of other risk factors if CPC isolated
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| Echogenic intracardiac focus (EIF): can be marker for trisomy 21, but in and of itself, not birth defect or indication of problem
in fetus; represents calcifications of papillary muscle; more common in nonwhite fetuses; not associated with congenital
heart disease; small association with chromosome abnormalities (trisomies 18 and 21); Caughey et al—
decision analysis of utility of amniocentesis for EIF as screening tool for Down syndrome (DS); performing amniocentesis
for isolated EIF would result in additional 120,000 amniocenteses to detect 244 fetuses with DS; amniocenteses
would result in 582 miscarriages (2.5 miscarriages for every DS case detected); instead, finding should be correlated
with other risk factors (eg, triple screen, maternal age) for chromosome abnormalities; not associated with heart defects,
so echocardiography not necessary; amniocentesis not recommended in absence of other risk factors
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| Findings of minimal significance to fetus: renal pelviectasis—dilation of anteroposterior (AP) diameter of renal
pelvis without frank hydronephrosis; almost always physiologic response of fetus to maternal hormones of pregnancy
and resolves after birth; in small percentage of cases, represents true pathology (eg, obstruction, reflux); analyzing
findings—AP diameter measured at <20 wk (upper limit of normal [ULN] 4 to 6 mm; <4-6 mm considered physiologic);
diameter up to 10 mm at 30 wk until term considered in mild range and associated with normal outcome after
birth; study looked at these particular cutoffs and found them predictive of normal outcome, with good sensitivity and
specificity; meta-analysis found that with mild pelviectasis, 98% of cases stable or improve over course of pregnancy;
follow-up—not necessary to follow serially with US; typically recommend repeat US in third trimester to rule out progression
and determine whether infant needs postnatal follow-up; risk for DS marginally increased (least helpful of all
“soft” markers in detecting DS); amniocentesis not recommended in absence of other risk factors; if pelviectasis persists
in third trimester, postnatal follow-up for at least 10 days after delivery recommended (maternal progesterone and other
hormones no longer in infant’s system); antibiotic prophylaxis recommended
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| Findings with potential for significant abnormality (but often seen in normal fetuses): probably most
problematic to counsel patients and manage
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| Echogenic bowel: varied appearance; can be diffuse or have multifocal calcifications; significant only if as bright as surrounding
bone; intra-abdominal calcifications can indicate meconium peritonitis, bowel obstruction, or primary problem
with gastrointestinal (GI) tract; can be associated with trisomies, cystic fibrosis (CF), viral infections (eg,
cytomegalovirus [CMV]), intrauterine growth retardation (IUGR), and fetal demise; study of 175 fetuses with
echogenic bowel found 5 cases of CF, 5 cases of aneuploidy (primarily DS), 1 case of CMV, and no toxoplasmosis; CF
screening of parents or fetus recommended; maternal testing for CMV with serology or amniocentesis; also test for
toxoplasmosis; unclear whether amniocentesis warranted in otherwise low-risk patient
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| Ventriculomegaly: difficult to counsel patients due to association with severe neurologic abnormalities in 10% to 20%
of cases; normal outcome in 80% to 90% of cases; can be marker for early hydrocephalus or underlying central nervous
system (CNS) pathology; bigger ventricles more common in male fetuses; when isolated, outcome usually normal;
when associated with other CNS or non-CNS findings, outcome much worse; 10 mm ULN; additional
testing—perform level II US to determine whether other structural abnormalities present; fetal magnetic resonance
imaging (MRI) also used (differentiation between gray and white matter; whether migrational abnormalities
present; development of gyri and sulci); amniocentesis recommended (4%-5% of cases due to DS or other chromosomal
abnormalities); also caused by viral infection (can do polymerase chain reaction [PCR] for CMV and toxoplasmosis)
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| Utility of US “soft” signs in screening for DS: second trimester US proposed as screening tool; useful for high-risk
women to avoid amniocentesis, and useful for low-risk women to find markers of DS and to decide whether risk for DS
higher than suspected (and whether amniocentesis necessary); data on utility of US inconsistent; in low-risk women—
large number of women must be screened to detect single DS case; for each detected DS case, several hundred false-positive
diagnoses; if amniocentesis performed to make diagnosis, fetal losses occur; in high-risk women—study by
Caughey; if amniocentesis performed on all women with positive triple screen, 5094 DS cases detected and 1931 cases
missed; if US screen added before amniocentesis, 2000 cases missed; if US screen used in low-risk population (normal triple
screen), 835 additional DS cases detected; compared to other screening strategies, US clearly not effective screening
tool; study by Smith-Bindman et al—meta-analysis; published in JAMA; analyzed use of second-trimester US for detecting
DS; looked at several markers and stratified results by other structural abnormalities; found that with isolated markers,
sensitivity very low and few cases of DS would have only isolated marker; false-positive rates high and because DS
rare, false positives more common than true positives; one exception nuchal fold (more specific for DS and not likely seen
as false positive); concluded that detection of pseudoabnormalities by US does not warrant amniocentesis in otherwise
low-risk patients; however, in high-risk patients, lack of such findings does not warrant forgoing amniocentesis; in borderline
cases, US to look for such findings may be useful to assist patient in decision making; take-home lessons—pseudoabnormalities
affect significant portion of prenatal US screenings; help women understand risks, benefits, and limitations of
these tests; carefully consider how to report “abnormal” results; important to provide accurate counseling, coordinated care,
and thoughtful follow-up after abnormal results
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| OPIOID ADDICTION IN PREGNANCY —Mavis N. Schorn, RN, CNM, Assistant Professor and Program Director,
Vanderbilt University School of Nursing, Nashville, TN
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| Who tends to misuse opioids: most often women in childbearing years (15 to 44 yr of age), well educated (several
years of college), more commonly white, usually employed, and often very functional; difficult to pick out misusers of
opiates
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| Risks in pregnancy: fetal growth restriction number one risk; second most common risk neonatal abstinence syndrome
(NAS; withdrawal from opioid); depending on specific opioid and method of treatment, ≤95% of infants have signs of
withdrawal after delivery
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| Related issues: tendency for more infections in women using opioids (screen for sexually transmitted diseases [STDs]
and hepatitis C virus [HCV]; also screen for tuberculosis [at high risk depending on where patient lives]); late or no prenatal
care common (heavy opioid use affects menstrual cycle, and patient unaware of pregnancy; fear of health care system);
poor nutrition; unfavorable living conditions (eg, domestic violence); exposure to high-risk behavior;
polysubstance abuse; significant use of nicotine (confounder in determining how much opioid use affects pregnancy);
low interest in treatment (pregnancy ideal time to help women change behavior and get out of cycle of addiction); dual
psychiatric diagnoses common; legal issues
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| Screening: Institute of Medicine (IOM) states all pregnant women should be screened for substance abuse; includes asking
questions when taking history and biologic testing; considerations—if selecting patients for screening based on appearance,
≥50% may be missed; protect confidentiality; informed consent necessary; parental permission required if
patient minor
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| Tips for obtaining history and physical examination: be nonjudgmental when asking questions; begin with less
stigmatized drugs; probe motivation for treatment; opioid addiction does not cause fetal anomalies (but growth restriction
issue); obtain thorough medical history; observe for signs of domestic violence; 66% of pregnancies unplanned and unwanted;
helpful questions targeted, open-ended, direct, and specific
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| Attributes of effective addiction-treatment provider: listed in Clinical Guidelines for the Use of Buprenorphine
in the Treatment of Opioid Addiction (government publication); establish trust; be direct, up-front, and friendly;
respectful; empathic; patient-centered approach
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| Treatment in pregnancy: encourage patient to enroll in regular treatment program—more likely to carry pregnancy
to full term; baby more likely to have average birth weight; decreases neonatal mortality; patient more likely to
get regular prenatal care; pharmacologic treatment includes methadone (standard pharmacologic treatment for pregnancy);
psychiatric care; baseline laboratory work (add HCV and liver function tests); consider purified protein derivative
(PPD) test
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| Methadone: advantages—reduces or eliminates drug cravings; blocks euphoric effects of narcotic drugs; improves
medical management and prenatal care; reduces illegal activity; reduces overdoses; reduces exposure to toxins in impure
street drugs; reduces exposure to infection from needles; improved employment and social activities;
disadvantages—high incidence of NAS (≈95%); low birth weight (may be due to eg, use of other opioids, smoking,
poor nutrition)
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| Buprenorphine: advantages—lower incidence of NAS; absence of major difference in perinatal outcome; patient feels
“normal”; opiate agonist antagonist; creates less dependence than opioid agonists; few side effects; easier to discontinue;
dosing and side effects—wide variation in dosage of methadone and buprenorphine; dose determined by whatever adequate
to reduce symptoms of drug craving; major side effect constipation
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| Common treatment myths: treatment produces 24-hr “high” (methadone has long half-life); prescribing medication
condones drug addiction (substitutes one for another); clients will continue to use illegal drugs; quick detoxification important
(using lowest dose possible runs risk of cravings); more difficult to quit treatment drugs than heroin; prescribing
opiates not appropriate for pregnant women (should stop drugs or go to jail); treatment causes extended drug withdrawal
in neonate; infants with NAS will have drug problems as adults; research clearly identifies best dose for preventing relapse
or reducing NAS
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| Opioid withdrawal in pregnancy: could have adverse effects on fetus; can lead to relapse; methadone has long half-
life, so do not withdraw quickly; buprenorphine has slow dissociation rate; narcotic antagonists (eg, naloxone [Narcan])
can trigger withdrawal in mother and baby; advancing pregnancy can require increase in dosage
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| Symptoms of opioid withdrawal: can occur as early as 8 to 24 hr after last use; early symptoms include lacrimation
and/or rhinorrhea, diaphoresis, yawning, insomnia, and restlessness; later symptoms include pupillary dilation, piloerection,
nausea or vomiting, muscle aches, and abdominal pain
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| Opioid intoxication: symptoms include drowsiness, slurred speech, intermittent dozing, pupillary constriction, bradycardia,
hypotension, and coma
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| Intrapartum considerations: effect on fetal heart rate (FHR) pattern (decreased variability, lower baseline, and fewer
portions of acceleration); no difference in outcome based on FHR; personal labor support minimal; fear of health care
personnel; poor venous access; pain tolerance may be low; methadone should be continued through labor but does not
provide adequate pain relief; can still use opioids in labor, but regional anesthesia preferred; avoid narcotics with mixed
agonist/antagonist properties (eg, butorphanol [Stadol], nalbuphine [Nubain]) because they can cause premature withdrawal
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| Postpartum considerations: fear of hospital personnel; concern about newborn withdrawal; breast-feeding and bonding
encouraged; child care and parenting education; social services
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| Newborn considerations: infant may require pharmacologic treatment for NAS; degree of NAS not necessarily related
to amount of drug used; NAS can be prolonged due to long half-life of methadone; majority of symptoms appear within
48 to 72 hr but can occur up to 3 wk after birth; standardized assessment tool available to evaluate symptoms; naloxone
not recommended; other medical problems may be present
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| Neonatal abstinence syndrome: 2 main issues include CNS irritability (high-pitched cry, inconsolability, tremors,
decreased sleeping, and seizures) and GI problems (uncoordinated suck, vomiting, and watery stools); treatment—
supportive; decrease stimuli (eg, lights) as much as possible; swaddle; massage; observe baby for sleeping, temperature,
feeding, weight loss or gain, or change in clinical status; pharmacologic treatment variable; resting infants on stomach related
to less severe withdrawal (but contrary to prevention of sudden infant death syndrome [SIDS]); teach parents about
handling and feeding baby
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| Questions and answers: how long do opioids show up in urine drug screen?—opioids clear fast (3-4 days); also
true for amphetamines, barbiturates, and cocaine; benzodiazepines and marijuana take ≈2 wk; what to do if suspect patient
self-medicating?—deal directly with patient and ask questions; if patient behaving in way not good for her and
baby, involve social services; perform drug screen
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Suggested Readings
Al-Kouatly HB et al: Factors associated with fetal demise in fetal echogenic bowel. Am J Obstet Gynecol 185:1039,
2001; Al-Kouatly HB et al: The clinical significance of fetal echogenic bowel. Am J Obstet Gynecol 185:1035, 2001;
Berghella V et al: Maternal methadone dose and neonatal withdrawal. Am J Obstet Gynecol 189:312, 2003; Caughey
AB et al: Nuchal translucency and first trimester biochemical markers for down syndrome screening: a cost-effectiveness
analysis. Am J Obstet Gynecol 187:1239, 2002; Caughey AB et al: The impact of the use of the isolated echogenic intracardiac
focus as a screen for Down syndrome in women under the age of 35 years. Am J Obstet Gynecol 185:1021,
2001; Coyle MG et al: Neurobehavioral effects of treatment for opiate withdrawal. Arch Dis Child Fetal Neonatal Ed
90:F73, 2005; Dashe JS et al: Improving the management of opioid-dependent pregnancies. Am J Obstet Gynecol
190:1806; author reply 1806, 2004; Dashe JS et al: Relationship between maternal methadone dosage and neonatal
withdrawal. Obstet Gynecol 100:1244, 2002; Demasio K et al: Isolated choroid plexus cyst in low-risk women less
than 35 years old. Am J Obstet Gynecol 187:1246, 2002; Johnson K et al: Treatment of neonatal abstinence syndrome.
Arch Dis Child Fetal Neonatal Ed 88:F2, 2003; Kuschel CA et al: Can methadone concentrations predict the severity
of withdrawal in infants at risk of neonatal abstinence syndrome? Arch Dis Child Fetal Neonatal Ed 89:F390, 2004; McCarthy
JJ et al: High-dose methadone maintenance in pregnancy: maternal and neonatal outcomes. Am J Obstet Gynecol
193:606, 2005; Nandakumar N et al: What is the best evidence based management of neonatal abstinence
syndrome? Arch Dis Child Fetal Neonatal Ed 91:F463, 2006; O'Brien C et al: Measurement of movement is an objective
method to assist in assessment of opiate withdrawal in newborns. Arch Dis Child Fetal Neonatal Ed 89:F305, 2004;
Rayburn WF et al: Pharmacotherapy for pregnant women with addictions. Am J Obstet Gynecol 191:1885, 2004;
Sharpe C et al: Outcomes of infants born to mothers receiving methadone for pain management in pregnancy. Arch Dis
Child Fetal Neonatal Ed 89:F33, 2004; Sidhu G et al: Outcome of isolated antenatal hydronephrosis: a systematic review
and meta-analysis. Pediatr Nephrol 21:218, 2006; Smith-Bindman R et al: Second-trimester ultrasound to detect
fetuses with Down syndrome: a meta-analysis. JAMA 285:1044, 2001
Educational Objectives
| The goals of this program are to improve interpretation of pseudo- and quasi-abnormalities found on ultrasonography
(US) during pregnancy and to improve management of opioid addiction in the pregnant patient. After hearing and assimilating
this program, the clinician will be better able to:
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| 1. Distinguish US findings in pregnancy that may be markers for abnormalities.
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| 2. Determine when amniocentesis is warranted based on US findings.
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| 3. Discuss the utility of US signs in screening for Down syndrome.
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| 4. Effectively treat opioid addiction in pregnancy.
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| 5. Manage neonatal abstinence syndrome.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty members to disclose relevant
financial relationships within the past 12 months that might create any personal conflicts of interest. Any identified conflicts
were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business or commercial
interest. For this program, the faculty reported nothing to disclose.
Acknowledgements
Dr. Norton was recorded at Antepartum and Intrapartum Management, held June 8-10, 2006, in San Francisco, CA, and
sponsored by the Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco.
Ms. Schorn was recorded at the 32nd Annual High-Risk Obstetrics Seminar, held December 8-9, 2006, in Nashville,
TN, and sponsored by the Vanderbilt University School of Medicine. The Audio-Digest Foundation thanks the
speakers and the sponsors for their cooperation in the production of this program.
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