Twin preg, unable to dtrm num plcnta & amnio sacs, 2nd tri

This code describes a twin gestation in the second trimester where the chorionicity (number of placentas) and amnionicity (number of amniotic sacs) have not been definitively determined. This often occurs when imaging is inconclusive or not yet performed to fully characterize the twin pregnancy.

Use this code when documentation indicates a twin pregnancy in the second trimester, but the specific details regarding whether the twins share a placenta (monochorionic) or have separate placentas (dichorionic), and whether they share an amniotic sac (monoamniotic) or have separate sacs (diamniotic), are unknown. This code is appropriate when the provider has not yet specified the chorionicity and amnionicity, or has explicitly stated "unable to determine."

• Do not use this code if the chorionicity and amnionicity are known; instead, select a more specific O30.0- subcategory.
• Ensure the documentation clearly specifies "second trimester" for accurate code assignment.
• This code is typically an interim diagnosis; coders should query for more specific information if available from subsequent imaging or provider notes.