Revenue Cycle Insider

Ob-Gyn Coding:

Use ‘0’ as the 7th Character With Single Gestation Maternal Complication Codes

Question: I’m new to ob-gyn coding and I’m having a lot of trouble understanding the errors of my coding. I’ve submitted several claims recently for patients who are pregnant with a single fetus, but all of the claims have received denials. Here is a sample of the diagnosis codes I’ve assigned:

  • O36.5931
  • O32.9XX1
  • O41.03X1
  • O35.9XX1

Can you help me?

AAPC Forum Subscriber

Answer: The error is with the 7th character. According to the ICD-10-CM Official Guidelines, Section I.C.15.a.6, you’ll use “0” as the 7th character when there is a single gestation.

Male experienced doctor examining young pregnant woman

In your case, if it is indeed documented that the patient is pregnant with a single fetus, then you’ll append “0” as the 7th character to show there is a single gestation. The additional 7th characters (“1,” “2,” “3,” etc.) are reserved for when the patient is pregnant with multiple gestations. In that case the physician may document fetus A and fetus B, which you could relate to 7th characters “1” and “2.”

Your corrected codes should appear as follows:

  • O36.5930 (Maternal care for other known or suspected poor fetal growth, third trimester, not applicable or unspecified)
  • O32.9XX0 (Maternal care for malpresentation of fetus, unspecified, not applicable or unspecified)
  • O41.03X0 (Oligohydramnios, third trimester, not applicable or unspecified)
  • O35.9XX0 (Maternal care for (suspected) fetal abnormality and damage, unspecified, not applicable or unspecified).

Mike Shaughnessy, BA, CPC, Production Editor, AAPC

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