ICD-9 Code 642.21

Other pre-existing hypertension, complicating pregnancy, childbirth, and the puerperium, delivered, with or without mention of antepartum condition

ICD-9: 642.21
Short Description:Old hyperten NEC-deliver
Long Description:Other pre-existing hypertension, complicating pregnancy, childbirth, and the puerperium, delivered, with or without mention of antepartum condition

Not Valid for Submission

ICD-9 642.21 is a legacy non-billable code used to specify a medical diagnosis of other pre-existing hypertension, complicating pregnancy, childbirth, and the puerperium, delivered, with or without mention of antepartum condition. This code was replaced on September 30, 2015 by its ICD-10 equivalent.

Convert 642.21 to ICD-10

The following crosswalk between ICD-9 to ICD-10 is based based on the General Equivalence Mappings (GEMS) information:

  • O10.111 - Pre-exist hyp heart disease comp pregnancy, first trimester
  • O10.112 - Pre-exist hyp heart disease comp pregnancy, second trimester
  • O10.113 - Pre-exist hyp heart disease comp pregnancy, third trimester
  • O10.12 - Pre-existing hypertensive heart disease comp childbirth
  • O10.211 - Pre-exist hyp chronic kidney disease comp preg, first tri
  • O10.212 - Pre-exist hyp chronic kidney disease comp preg, second tri
  • O10.213 - Pre-exist hyp chronic kidney disease comp preg, third tri
  • O10.22 - Pre-existing hyp chronic kidney disease comp childbirth
  • O10.311 - Pre-exist hyp heart and chr kidney dis comp preg, first tri
  • O10.312 - Pre-exist hyp heart and chr kidney dis comp preg, second tri
  • O10.313 - Pre-exist hyp heart and chr kidney dis comp preg, third tri
  • O10.32 - Pre-exist hyp heart and chronic kidney disease comp chldbrth
  • O11.1 - Pre-existing hypertension w pre-eclampsia, first trimester
  • O11.2 - Pre-existing hypertension w pre-eclampsia, second trimester
  • O11.3 - Pre-existing hypertension w pre-eclampsia, third trimester

Code Classification

  • Complications of pregnancy, childbirth, and the puerperium (630–679)
    • Complications mainly related to pregnancy (640-649)
      • 642 Hypertension complicating pregnancy, childbirth, and the puerperium

Information for Medical Professionals

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-9 Code Edits are applicable to this code:

Information for Patients


High Blood Pressure in Pregnancy

If you are pregnant, high blood pressure can cause problems for you and your unborn baby. You may have had high blood pressure before you got pregnant. Or you may get it once you are pregnant - a condition called gestational hypertension. Either one can cause low birth weight or premature delivery of the baby.

Controlling your blood pressure during pregnancy and getting regular prenatal care are important for the health of you and your baby. Treatments for high blood pressure in pregnancy may include close monitoring of the baby, lifestyle changes, and certain medicines.

Some pregnant women with high blood pressure develop preeclampsia. It's a sudden increase in blood pressure after the 20th week of pregnancy. It can be life-threatening for both you and the unborn baby. There is no proven way to prevent it. Most women who have signs of preeclampsia are closely monitored to lessen or avoid complications. The only way to "cure" preeclampsia is to deliver the baby.

NIH: National Heart, Lung, and Blood Institute

  • Eclampsia
  • HELLP syndrome
  • Preeclampsia
  • Preeclampsia - self-care

[Read More]

ICD-9 Footnotes

General Equivalence Map Definitions
The ICD-9 and ICD-10 GEMs are used to facilitate linking between the diagnosis codes in ICD-9-CM and the new ICD-10-CM code set. The GEMs are the raw material from which providers, health information vendors and payers can derive specific applied mappings to meet their needs.

  • Approximate Flag - The approximate flag is on, indicating that the relationship between the code in the source system and the code in the target system is an approximate equivalent.
  • No Map Flag - The no map flag indicates that a code in the source system is not linked to any code in the target system.
  • Combination Flag - The combination flag indicates that more than one code in the target system is required to satisfy the full equivalent meaning of a code in the source system.