O14.12 Severe pre-eclampsia, second trimester

Billable ICD-10-CM code, FY2026. Acts as a Major Complication or Comorbidity (MCC) as a secondary diagnosis.

Applies from O14 Pre-eclampsia

Excludes1 (never code together)

• pre-existing hypertension with pre-eclampsia (O11)

Applies from O14.1 Severe pre-eclampsia

Excludes1 (never code together)

• HELLP syndrome (O14.2-)

MS-DRG index

Defines the logic of DRG(s) 817-819 in MDC 14.

Approximate ICD-9-CM (GEMs)

• 642.51 Severe pre-eclampsia, delivered, with or without mention of antepartum condition (approximate)
• 642.52 Severe pre-eclampsia, delivered, with mention of postpartum complication (approximate)
• 642.53 Severe pre-eclampsia, antepartum condition or complication (approximate)
• 642.54 Severe pre-eclampsia, postpartum condition or complication (approximate)

Medicare Code Edits (MCE v43.1 (April 2026))

• Maternity diagnoses (age 9 through 64): Age conflict edit. These diagnoses are clinically expected only in patients age 9 through 64.

Code annotations containing back-references to O14.12

Back-references to O14

• Type 1 Excludes: I10 Essential (primary) hypertension ("hypertensive disease complicating pregnancy, childbirth and the puerperium (O10-O11, O13-O16)")
• Type 2 Excludes: O99.4 Diseases of the circulatory system complicating pregnancy, childbirth and the puerperium ("hypertensive disorders (O10-O16)")

Nearby codes

• O14.03 Mild to moderate pre-eclampsia, third trimester
• O14.04 Mild to moderate pre-eclampsia, complicating childbirth
• O14.05 Mild to moderate pre-eclampsia, complicating the puerperium
• O14.1 Severe pre-eclampsia
• O14.10 Severe pre-eclampsia, unspecified trimester
• O14.12 Severe pre-eclampsia, second trimester (this code)
• O14.13 Severe pre-eclampsia, third trimester
• O14.14 Severe pre-eclampsia complicating childbirth
• O14.15 Severe pre-eclampsia, complicating the puerperium
• O14.2 HELLP syndrome
• O14.20 HELLP syndrome (HELLP), unspecified trimester