Where Risk and Choice and Hope Converge, a Guiding Voice

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Where Risk and Choice and Hope Converge, a
Guiding Voice

• By JAN HOFFMAN, NY Times
• September 18, 2007

http//www.nytimes.com/2007/09/18/health/18tren.ht
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Pregnancy Screening

• The young couple, shy and flush with excitement
  about her first pregnancy, sit down with Daniela
  Iacoboni, a prenatal genetic counselor at North
  Central Bronx Hospital. They are from Mexico and
  speak no English.
• Do you know why youre here today? Ms. Iacoboni
  asks in Spanish.
• They do not.
• The results from your blood test showed positive
  for Down syndrome, Ms. Iacoboni says.
• No response.
• Mongolismo, she says.
• The couple smile nervously.
• Ms. Iacoboni asks them whether they know about
  chromosomes.
• They do not.

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Difficult Decisions

• Even though medical advances have improved
  first-trimester screenings, many of these
  patients do not realize early on that they are
  pregnant, are in denial or have pressing life
  problems that prevent them from keeping
  appointments.
• Some do not have partners. Earlier this morning,
  a 37-year-old patient who spoke only Mandingo sat
  with her head bowed, as her husband declared that
  because his other children were born healthy,
  there was no need to test this one. One patient
  is homeless another became pregnant and
  HIV-positive after she was raped
• She shows the Mexican couple a chromosome chart.
  The blood test is a maybe, she says, and
  because the woman is 27, chances are good that
  her baby will be fine.
• The only way to know for certain before the baby
  is born, she continues, is to do an
  amniocentesis. Es opcional, she adds. Es tu
  decisión.
• The doctor will use a needle to take a sample of
  the fluid surrounding the baby.
• The couple grow pale and shift in their seats. No.

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Screening has its risks

• Ms. Iacoboni lays out the consequences of
  learning more that amniocentesis has a small
  risk 1 in 500 of miscarriage.
• They begin shaking their heads.
• Faced with a quandary, patients often ask Ms.
  Iacoboni what she would do.
• I say, Its not my place to tell you, Ms.
  Iacoboni says later. And if I were you, I
  wouldnt want me telling you to have a needle
  stuck in you that has any kind of a risk and
  its also not my place to say you shouldnt. Your
  religious beliefs, home support, financial
  situation are individual. The two worst things
  that could happen are, you could lose a healthy
  baby or you could learn you have a Down syndrome
  baby. You have to decide which risk is worse for
  you.
• Ms. Iacoboni gently tells the couple that many
  problems diagnosed by an amniocentesis have no
  cures.
• No, they say.
• That when some women learn the results, they keep
  their pregnancies. Others do not.

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Procedures and Risks

• Blood screening is the first test.
• If it comes up positive, others are needed for
  verification.
• For further details, see genetic testing.

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The Economics
True Condition
No
Yes

• Perfect screening tests
• Verify the positive (sensitivity)
• Verify the negative (specificity)

Specificity
No
Test Result
Sensitivity
Yes
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Issues
True Condition

• Type I vs. Type II Error
• I False Positive
• II False Negative
• Tests levels are not perfect. Increasing
  sensitivity ? increasing False !!

No
Yes
False
Specificity
No
Test Result
False
Sensitivity

• What do you do, if you have a true positive.
  Economists can tell costs and benefits. Patients
  must make decisions.

Yes