The International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) is currently being used in most countries. The United States is among a very few industrialized nations still using the ICD-9 code set for diagnosis code reporting. After an initial delay, the Department of Health and Human Services (HHS) announced in the August 2012 final rule that the ICD-10 implementation date would be October 1, 2014 rather than the previously scheduled date of October 1, 2013.

Due to legislative intervention this year, ICD-10 implementation has been delayed again and will be implemented no sooner than October 1, 2015.

ICD-10-CM contains 21 chapters listing three to seven digit alphanumeric codes. Currently there are more than 79,000 ICD-10-CM diagnosis codes, which is about 65,000 more codes than currently exist in ICD-9-CM.

ICD-10-CM allows coding for increased specificity in the reporting of diseases and recently recognized conditions. Further, ICD–10–CM provides noteworthy improvements over ICD–9–CM in coding primary care encounters, external causes of injury, mental disorders, neoplasms, and preventive health. The ICD–10–CM code set reflects advances in medicine and medical technology, permits the capture of more socioeconomics details, ambulatory care condition information, problems related to lifestyle, and the results of screening tests.

The pending ICD-10 implementation means that physicians need to ensure that by October 1, 2015, their chart documentation will support the increased clinical specificity of the new code set. This will enable proper code selection and will result in fewer claim denials

ICD-10 provides additional clarity that benefits obstetrics and gynecology coding. Some of the obstetrical coding enhancements include:

1. Elimination of episodes of care for obstetric codes
2. Changes in time frames:

  1. Abortion vs. Fetal death (20 weeks)
  2. Early vs. Late pregnancy (20 weeks)
  3. Code extensions to denote the specific fetus in multiple gestation pregnancies

One other notable enhancement is that ICD-10-CM allows the trimester of pregnancy to be designated. Here is an example of the difference:

649.53 Spotting complicating pregnancy, antepartum O26.851 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

Note that the ICD-10-CM diagnostic codes for obstetrical conditions begin with the letter "O".

ICD-10-CM also provides the ability to report the specific gestational week of pregnancy with codes from category Z3A. Gestational week codes would be reported in addition to codes for complications of pregnancy.  Here is an example of the gestational week code structure:

Z3A.0 Weeks of gestation of pregnancy, unspecified or less than 10 weeks
Z3A.00 Weeks of gestation of pregnancy not specified
Z3A.01 Less than 8 weeks gestation of pregnancy
Z3A.08 8 weeks gestation of pregnancy
Z3A.09 9 weeks gestation of pregnancy

Since annual updates to ICD-9 CM and ICD-10 make transition planning difficult, vendors, system maintainers, payers, and educators requested a code freeze. As a result, the last regular, annual updates to both ICD-9-CM and ICD-10-CM were made on Oct 1, 2011. Limited code updates in years 2012 - 2015 will be permitted in order to capture new technology and new diseases:

October 1, 2011 – last regular updates to ICD-9-CM and ICD-10-CM/PCS occurred
October 1, 2012 and 2014 – partial code freeze, only codes for new technologies and new diseases will be considered for ICD-9-CM and ICD-10-CM/PCS
October 1, 2015 – implementation date for ICD-10-CM/PCS. Only codes for new technologies and new diseases will be considered for ICD-10-CM/PCS. No new ICD-9-CM codes.
October 1, 2016 – regular updates to ICD-10-CM/PCS will begin.

Providers need to prepare for the change to ICD-10 and educate themselves and their staff on the updated code set.

The implementation delay provides additional time to evaluate and make any needed changes to your documentation process to ensure timely and accurate claims in 2015. As indicated in the examples above, ICD-10 code selection will require a much greater level of detail to be documented due to the granularity of ICD-10.


ACOG is offering multiple ICD-10-CM training opportunities. All remaining Coding Workshops for 2015 are sold out. Due to the sold out status, no onsite registrations will be permitted. The 2016 Coding Workshops are scheduled to be posted and available for registration starting on October 1, 2015.

In the meantime, ACOG’s coding resources provide tools and guidance needed to code claims faster and more accurately.


Donna Tyler
Manager, Coding Education

Keisha Sutton
Coding Specialist

American Congress of Obstetricians and Gynecologists
409 12th Street SW, Washington, DC  20024-2188 | Mailing Address: PO Box 70620, Washington, DC 20024-9998