Coding Guidance for Monochorionic Diamniotic Twin Pregnancies
The Society for Maternal-Fetal Medicine (SMFM) Coding Committee; Mathew Esposito MD; Steve Rad, MD; Trisha Malisch, CCS-P, CPC; Fadi Bsat, MD; Vanita Jain, MD.
The purpose of this coding tip is to provide guidance in coding service for patients with monochorionic diamniotic twins. SMFM has published guidelines on the appropriate evaluation and management of monochorionic/diamniotic twin gestations (see SMFM Special Statement: Updated Checklists for Management of Monochorionic Twin pregnancy https://www.smfm.org/publications/336-smfm-special-statement-updated-checklists-for-management-of-monochorionic-twin-pregnancy; ACOG PB #231: Multifetal Gestations). Such patients typically have serial ultrasounds performed beginning in the second trimester to investigate for evidence of Twin-to-Twin transfusion syndrome (TTTS) and other complications of monochorionic twinning. This tip is not intended to provide clinical guidance, though rather to identify the billing and CPT codes for the care that is provided. We share several scenarios to help guide coding in your practice.
Q1. For monochorionic/diamniotic twin gestations, our practice usually initiates a detailed fetal anatomic assessment between 18-20 weeks gestation. After first trimester ultrasounds (for fetal number/chorionicity, and/or nuchal translucency assessment), we initiate the assessment for TTTS at 16 weeks gestation. We do not attempt to complete an anatomic study at this time beyond assessing those features relevant for TTTS assessment. At the 18 week study, we perform a complete anatomic study for each twin. Assessment for TTTS follows thereafter with subsequent ultrasound studies performed every 2 weeks. How should this be billed?
A1. 76815 x1 (if initial visit/new patient) or 76816 x2 (if follow up visit/established patient who has had prior ultrasounds at the practice) for the early second trimester study (16 weeks). 76811/76812 for the second study (18 weeks). 76816 x2 for the subsequent studies (20 weeks and beyond) assuming assessment of fetal biometry and relevant anatomy appropriate for TTTS screening.
Q2. For monochorionic/diamniotic twin gestations, our practice usually initiates the fetal anatomic assessment in the early second trimester. At 16 weeks gestation, we perform a complete anatomic study. Assessment for TTTS follows with subsequent ultrasound studies performed every 2 weeks thereafter. In those cases in which not all anatomic features are seen at 16 weeks gestation, we attempt re-visualization with scheduled TTTS screening. How should this be billed?
A2. 76811/76812 for the first study (16 weeks). 76816 x2 for the subsequent studies (18 weeks and beyond). This is irrespective as to whether these follow up studies are re-assessing limited fetal anatomic views or performing a TTTS screening (with required assessment of fetal biometry and relevant anatomy).
Q3. For monochorionic/diamniotic twin gestations our practice usually initiates the fetal anatomic assessment in the first trimester with a detailed first trimester fetal survey at 12-13 weeks. Our next ultrasound is typically scheduled at 16 weeks with follow-ups schedule every 2 weeks thereafter. At the 16 week study we do not re-attempt to complete an anatomic study beyond assessing those features required to assess for TTTS. At the 18 week study, we perform a detailed second trimester anatomic study. Assessment for TTTS follows thereafter with subsequent ultrasound studies performed every 2 weeks. How should this be billed?
A3. 76801/2+76813/4 for the first trimester detailed fetal assessment. 76816 x2 at 16 weeks gestation for the TTTS assessment. 76811/76812 for the detailed second trimester fetal anatomy study (18 weeks). 76816 x2 for the subsequent studies (20 weeks and beyond) assuming assessment of fetal biometry and relevant anatomy appropriate for TTTS screening.
Rationale: The correct code to bill is always based on the study performed. At 16 weeks gestation, the appropriate code should be billed based on the actual service rendered. If the patient is new to the practice (and/or has not undergone a detailed fetal anatomic assessment) and only a limited ultrasound is performed (ie, fetal anatomical structures are not comprehensively imaged), it is only appropriate to bill 76815 (to be billed once, regardless of fetus number). A physician cannot use 76816 instead because that CPT code is only for follow-up ultrasounds after a comprehensive anatomic study. 76811/76812 should be reserved and billed at the time the detailed second trimester fetal anatomic survey is actually performed in your practice (16-22 weeks).
At 16 weeks gestation, if a detailed second trimester anatomic study is performed, 76811/76812 should be billed. Subsequent ultrasounds screening for TTTS would be therefore billed as follow up ultrasound studies (76816 x2) appending a 59-modifier to the second 76816 CPT.
If the patient is not new to the practice and has undergone Detailed Diagnostic First Trimester Obstetric Ultrasound (ie, first trimester anatomy study), an ultrasound evaluation for TTTS at 16 weeks may be considered a follow up study. In this case, it would be appropriate to bill 76816 x2 with the appropriate 59-modifier for that study. At the time a detailed second trimester fetal anatomic survey is provided (16-22 weeks) it would be appropriate to bill 76811/76812. Subsequent ultrasounds would be billed 76816 x2 thereafter, appending a 59-modifier to the second 76816 CPT.
Documentation in all scenarios must support the CPT billed.