COBGC ICD-10 Coding for OB/GYN 2 — Questions and Answers
Question 1: A patient is 20 weeks pregnant and diagnosed with gestational hypertension without significant proteinuria. Which ICD-10-CM code is correct?
- O10.012 – Pre-existing essential hypertension, second trimester
- O13.2 – Gestational hypertension without significant proteinuria, second trimester (Correct answer)
- O14.02 – Mild to moderate pre-eclampsia, second trimester
- O11.2 – Pre-existing hypertension with superimposed pre-eclampsia, second trimester
Correct answer: O13.2 – Gestational hypertension without significant proteinuria, second trimester
O13.2 is used for gestational (pregnancy-induced) hypertension without significant proteinuria occurring in the second trimester (14–27 weeks).
Question 2: What is the correct ICD-10-CM code for pre-existing essential hypertension complicating pregnancy in the third trimester?
- O10.013 – Pre-existing essential hypertension complicating pregnancy, third trimester (Correct answer)
- O10.413 – Pre-existing secondary hypertension, third trimester
- O11.3 – Pre-existing hypertension with superimposed pre-eclampsia, third trimester
- O13.3 – Gestational hypertension without proteinuria, third trimester
Correct answer: O10.013 – Pre-existing essential hypertension complicating pregnancy, third trimester
O10.013 represents pre-existing essential hypertension (subcategory O10.0) complicating pregnancy specifically in the third trimester.
Question 3: In ICD-10-CM, when coding a complication affecting a specific fetus in a multiple gestation pregnancy, which character position identifies the fetus number?
- 5th character
- 6th character
- 7th character (Correct answer)
- 4th character
Correct answer: 7th character
The 7th character in ICD-10-CM obstetric codes identifies the affected fetus in multiple gestation (0 = not applicable, 1–5 = individual fetuses, 9 = other fetus).
Question 4: A patient has gestational diabetes mellitus during pregnancy that requires insulin for control. Which ICD-10-CM code applies?
- O24.410 – Gestational diabetes mellitus in pregnancy, diet controlled
- O24.414 – Gestational diabetes mellitus in pregnancy, insulin controlled (Correct answer)
- O24.112 – Pre-existing type 2 diabetes mellitus in pregnancy, second trimester
- E11.649 – Type 2 diabetes mellitus with hypoglycemia without coma
Correct answer: O24.414 – Gestational diabetes mellitus in pregnancy, insulin controlled
O24.414 is the correct code for gestational diabetes mellitus in pregnancy that is controlled by insulin.
Question 5: A patient at 28 weeks gestation develops severe preeclampsia. Which ICD-10-CM code is correct?
- O14.03 – Mild to moderate pre-eclampsia, third trimester
- O14.13 – Severe pre-eclampsia, third trimester (Correct answer)
- O15.03 – Eclampsia in the third trimester
- O11.3 – Pre-existing hypertension with superimposed pre-eclampsia, third trimester
Correct answer: O14.13 – Severe pre-eclampsia, third trimester
28 weeks falls in the third trimester; severe preeclampsia uses subcategory O14.1, and the third-trimester designation yields O14.13.
Question 6: Eclampsia occurring during the postpartum (puerperal) period is coded as:
- O15.9 – Eclampsia, unspecified as to time period
- O15.2 – Eclampsia in the puerperium (Correct answer)
- O15.03 – Eclampsia in the third trimester
- O90.4 – Postpartum acute kidney failure
Correct answer: O15.2 – Eclampsia in the puerperium
O15.2 specifically identifies eclampsia occurring in the puerperium (postpartum period), distinct from eclampsia in pregnancy or labor.
Question 7: According to ICD-10-CM guidelines, a code from category Z3A (Weeks of gestation) should be assigned:
- As a principal diagnosis when gestational age is the primary reason for the encounter
- As an additional code whenever applicable to provide the specific gestational age (Correct answer)
- Only when the patient is in the third trimester and at risk for preterm delivery
- Only for high-risk pregnancies requiring special monitoring
Correct answer: As an additional code whenever applicable to provide the specific gestational age
Z3A codes are always secondary/additional codes used to specify the number of completed weeks of gestation; they are never sequenced as principal diagnosis.
COBGC ICD-10 Coding for OB/GYN 2
A patient is 20 weeks pregnant and diagnosed with gestational hypertension without significant proteinuria.
Which ICD-10-CM code is correct?