Ob-Gyn Coding Alert

Tip: Over 42 weeks means you should opt for “prolonged” code.

Patients whose pregnancies last longer than 40 weeks gestation are either labeled “post term pregnancies” (40-42 weeks) or “prolonged pregnancies” (over 42 weeks). 

ICD-9-CM Codes: Currently, you should report this condition with the following diagnosis codes:

• 645.10, Post term pregnancy, unspecified episode of care 

• 645.11, ... delivered, with or without antepartum condition

• 645.13, ... antepartum condition or complication

• 645.20, Prolonged pregnancy, unspecified episode of care 

• 645.21, ... delivered, with or without antepartum condition

• 645.23, ... antepartum condition or complication

ICD-10-CM Codes: As of October 1, 2015, you will report the following diagnosis codes:

• O48.0, Post-term pregnancy

• O48.1, Prolonged pregnancy

ICD-10-CM Change: In ICD-9, you have multiple options for both post-term and prolonged pregnancies, based on whether the patient delivers or is still pregnant. ICD-10 simplifies that and gives you only two options: post-term (O48.0) or prolonged (O48.1). 

Documentation: You should report O48.0 when the physician documents the patient’s pregnancy is over 40-42 weeks completed gestation (that is, 40 weeks 1 day to 42 weeks 0 days). You should report O48.1 when the physician documents the patient’s pregnancy has advanced over 42 weeks of completed gestation (42 weeks at 1 day or longer).  But remember that you must also report a Z3A diagnosis that indicates the week gestation on the date you report her late pregnancy.  

Here is how you will find these codes in your Alphabetic Index: 

Post-dates (40-42 weeks) (pregnancy) (mother) O48.0

- more than 42 weeks gestation O48.1

Post-term (40-42 weeks) (pregnancy) (mother) O48.0

- more than 42 weeks gestation (mother) O48.1

Postmaturity, postmature (over 42 weeks)

- maternal (over 42 weeks gestation) O48.1

Pregnancy (childbirth) (labor) (puerperium) —see also Delivery and Puerperal

Note: the tabular must be reviewed for assignment of the final character for trimester, the tabular must be reviewed for assignment of the correct extension for multiple gestations for all chapter 15 codes

• complicated by (care of) (management affected by)

• postmaturity (post-term) (40 to 42 weeks) O48.0

• more than 42 completed weeks gestation (prolonged) O48.1

• post-term (40 to 42 weeks) O48.0

• postmature (40 to 42 weeks) O48.0

• more than 42 weeks gestation O48.1

• prolonged (more than 42 weeks gestation) O48.1

Prolonged, prolongation (of)

• gestation (over 42 completed weeks)

• mother O48.1

• pregnancy (more than 42 weeks gestation) O48.1

Coder Tips: Check your physician’s documentation for how many weeks gestation the pregnancy is.