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Coding Conditions that take place in Pregnancy, Childbirth, and the Puerperium

Encounters for patients who are pregnant, in delivery, or in the puerperium, use codes from Chapter 15 Pregnancy, Childbirth and the Puerperium (O00-O9A).  There are key data points and specific guidelines that must be followed.  As with all coding, remember to imagine how the story unfolded and aim to relay that story with the correct codes. A well-documented provider’s note related to the care of an antepartum or postpartum patient will include background information about the pregnancy, circumstances around the admission, labor, delivery, the gestational age of the fetus (or fetuses), complications, and outcome.

Two important things to remember when coding from Chapter 15:

First, codes from Chapter 15 have sequencing priority over all other chapters in ICD-10-CM; be sure they are the Principal Diagnosis (or first-listed code in the outpatient setting). The exception to this is if a pregnant woman is seen for an unrelated injury (e.g., a broken hand after slipping on ice, etc.). While she is in fact pregnant, her pregnancy is not the reason for the encounter, and therefore, using the code Z33.1, Pregnant state, incidental, would be appropriate; Z33.1 is not a valid PDx or first listed code, therefore, sequence it after the primary reason for the encounter.

Second, Chapter 15 codes should only appear on the mother’s record, not on the child’s.

Once these details are identified, begin coding for maternal conditions, high-risk pregnancy, and abortive outcomes.

Assigning a code for the trimester and number of weeks of gestation are a vital detail in relaying the story of the visit. Many of the Chapter 15 codes have a final character that indicate the trimester of pregnancy.

For example:

O26.85 Spotting complicating pregnancy, first trimester

O26.852 Spotting complicating pregnancy, second trimester

O26.853 Spotting complicating pregnancy, third trimester

O26.859 Spotting complicating pregnancy, unspecified trimester

Determination of trimester is calculated from first day of last menstrual period, and is documented in weeks. The first trimester is less than 14 weeks, 0 days; the second trimester is between 14 weeks, 0 days, and 27 weeks and 6 days; and the final trimester is 28 weeks through delivery. A normal pregnancy is between 38 and 42 weeks.  Determining the trimester is reliant on the provider’s documentation. The code for “unspecified trimester” should only be used if there is no documentation pertaining to trimester documented in the chart. Because this information is so important, let your provider know that this must be documented. 

Code the outcome of delivery with Z37.- and the number of weeks of gestation using Z3A.-. If the patient delivers before arriving at the hospital, assign code Z39.0, Encounter for care and examination of mother immediately after delivery. (Note: this would mean that the mother is no longer pregnant, so the O code would no longer be applicable).

These are just some of the basic guidelines to ensure accurate coding for pregnancy, childbirth, and the puerperium. Complications, abortive outcomes, and other diseases and pre-existing conditions can play a major role in changing the story of the patient’s visit. Stay tuned for more!