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Monochorionic Twins Recommendations

Thumbnail of Monochorionic Twin BrochureThe following recommendations are meant for both patients and their providers as guidance during a pregnancy with monochorionic twins. For questions and referrals please call us at 1-800-RX-FETUS.

You can also download and print this information with our Monochorionic Twins Recommendations PDF brochure.

Monochorionic Twins Recommendations

Complications Unique to Monochorionic Twins

  • Amniotic fluid discordance
  • Growth discordance ( > 20%)
  • Unequal placental sharing
  • Selective intrauterine growth restriction (S-IUGR) in one fetus
  • TTTS - clinically defined as a deepest vertical pocket of > 8 cm in one twin and < 2 cm in in the other twin, simultaneously. Note: growth discordance may also be seen but not necessary for the diagnosis.
  • Anomalies in on fetus
  • TRAP Sequence

Components of UCSF Evaluation

  • Level II anatomic survey for fetal anomalies
  • Special attention paid to cord insertions and vascular mapping
  • Fetal echocardiagraphy both for the structural integrity and functional (systolic and diastolic) pathology
  • Fetal brain MRI > 22 weeks when indicated and appropriate

Potential Surgical Procedures

  • Selective fetoscopic laser ablation
  • Radiofrequency ablation (RFA) cord occlusion

Timeframe for Referrals to UCSF

Consider Referral

  • Significant amniotic fluid discordance
    While TTTS is defined as having a DVP > 8 cm and < 2 cm simultaneously, we encourage referral for evaluation if the fluid pockets become significantly discordant even before TTTS criteria are met
  • Significant growth discordance defined as > 20% difference
  • Polyhydramnios in one twin with normal fluid in the other
  • Suspicion of discordant anomaly

We encourage you to call our center to discuss your findings if you have concerns at 1-800-RX-FETUS

Call for Timely Referral (need to see patient within 1 week)

  • DVP > 8 cm and < 2 cm with bladder visualized in donor and normal umbilical artery dopplers

Call for Urgent Referral (need to see patient within a couple days)

  • DVP > 8 cm and < 2 cm with no visible bladder in donor and/or abnormal umbilical doppler
  • Suspected Hydrops

What is Needed For Referral

Patients referred to UCSF for an evaluation should have the following faxed to 415-502-0660:

  • Demographic information
  • A copy of the front/back of their health insurance card
  • All OB/Perinatal medical records
  • If insurance authorization is required, please download the Monochorionic Evaluation Codes PDF for the proper codes.
Last Updated: 3/4/2010
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