Ob-Gyn Coding Alert

Question: A patient transferred to our practice with a premature rupture of membranes of a twin at 21 5/7 weeks. Twin A was delivered vaginally but died shortly after birth. Twin B was delivered five days later. What are the appropriate CPT and ICD-9 codes for twin A?

New York Subscriber

Answer: This case is tricky to code because of what is happening to the two babies. Twin A was born alive, therefore you can use 644.21 (early onset of delivery before 37 completed weeks of gestation). You can also add a second code for premature rupture of membranes (658.11). In Twin Bs case, the fetus is over 22 weeks gestation and a delivery can be linked to 644.21, but the second code should be 658.21 (delayed delivery after spontaneous or unspecified rupture of membranes). You should consider adding a third diagnosis, 651.3 (twin pregnancy with fetal loss and retention of one fetus), if you are billing for Twin As delivery before the entire outcome is known. The American College of Obstetricians and Gynecologists (ACOG) coding committee has stated that the correct CPT code for the delivery of a fetus greater than 20 weeks, zero days gestation is the appropriate delivery code. The second twin was delivered five days later, which makes it the same diagnosis as Twin A (644.21). It would be best to bill for the entire global at the end with delivery of Twin B, and because both were vaginal births, code 59400 for Twin B and 59409-59 for Twin A. Modifier -59 (distinct procedural service) is preferable because there are two different patients (Twin A and Twin B), rather than the same procedure repeated on the same patient.