I found this info on whay modifier to use when billing for
Global OB claims (CPT-4 codes 59400, 59510, 59610 and 59618) must be billed in the “from-through” billing format (called “from-to” on
the CMS-1500) with modifier AG (primary surgeon). The “from” date
of service is the first date the recipient was seen for this pregnancy, and the “through” or “to” date of service is the date of the delivery. Enter a quantity of “1” in the Days or Units field (Box 24G).
Hospital Services
99221-99223 Initial hospital care codes
These are the "initial hospital care" codes used by family physicians for coding their admission history and physical services for hospitalized patients. The global codes (59400, 59510) do not include initial or subsequent hospital services by the physician if the patient does not deliver. Physicians should code admissions (in-patient or out-patient) for false labor, out-patient PG gel, stress tests or medical/surgical complications separately.
The criteria used for utilizing these codes with a maternity care patient are absolutely no different than any other patient; however, a physician cannot use these codes in conjunction with the global codes 59400 or 59510, as the global codes already include initial hospital care for the patient who delivers.
Also check out thi8s website as it gives some goon info:
http://www.dss.mo.gov/dms/providers/education/pro/pro09.pdf
Good Luck!
