Introduction

This concept describes the method used at MCHP to identify the outcome of delivery, focusing on the maternal / mother's birth of her child in a hospital. The methodology is based on the type of abstract record and specific ICD (International Classification of Diseases) and CCI (Canadian Classification of Health Interventions) codes contained in the Hospital Abstracts data. The concept also explains why specific ICD-10 outcome of delivery diagnosis codes cannot be used in this methodology.

The majority of information for this concept is taken from other concepts related to this topic, and from discussion amongst the MCHP analysts.

MCHP's Algorithm for Identifying the Outcome of Delivery

The MCHP algorithm for identifying the outcome of delivery from maternal hospital abstracts includes the following conditions using data contained in the Hospital Abstract records:


• Abstract Type - the variable ABSTYPE or ABSTRACTTYPE, depending on the year of the abstract record, with a value = "3", is used to identify an obstetrical / maternal abstract. Please see point 3 of the Cautions / Notes section below for more information on the use of "abstract type".
  
  
• Diagnosis Code(s) - at least one diagnosis code with a 3-digit value starting with "V27" (for abstract records prior to April 1, 2004 using ICD-9-CM coding) OR starting with "Z37" (for abstract records after March 31, 2004 using ICD-10-CA coding). These values represent the outcome of delivery recorded on the mother's / maternal hospital abstract record. The full length of these codes specify either a live birth or stillbirth for single or multiple births.
  
  NOTE Pregnancies ending in outcomes other than a live birth or stillbirth, such as an abortion or ectopic pregnancy, are coded differently and will not contain the "V27" or "Z37" code values in the abstract record.
  
  
• Procedure / Intervention Codes - procedure / intervention codes and other hospital abstract variables are used to identify delivery by caesarean section or assisted delivery using forceps or vacuum extraction, depending on the level of detail required for a research project.
  
  
  • Deliveries by C-section are identified using ICD-9-CM procedure codes or specific hospital abstract variables (prior to April 1, 2004) or CCI intervention codes (after March 31, 2004). For more detailed information, see the Caesarean / Cesarean Section (C-Section) concept.
    
    
  • Assisted vaginal deliveries using forceps or vacuum extraction can be identified using ICD-9-CM procedure codes (prior to April 1, 2004) or CCI intervention codes (after March 31, 2004). For more detailed information, see the Assisted Vaginal Birth glossary term and the Complications of Labour and Delivery concept.

ICD-10 Versus ICD-10-CA Coding

The Hospital Abstracts data held in the MCHP Data Repository uses the International Classification of Diseases, 10th Revision, with Canadian Enhancements (ICD-10-CA) coding system starting on April 1, 2004 and follows national standards for abstracting developed by the Canadian Institute of Health Information (CIHI).

The International Classification of Diseases, 10th Revision (ICD-10) from the World Health Organization (WHO) and the ICD-10-CA coding systems are identical at the fourth digit level, although there are some differences in the interpretation or use of some codes.

In ICD-10, there are specific diagnoses codes in chapter XV, starting with the letter O, that relate to pregnancy, childbirth and the puerperium. A range of codes, from O80 to O84 are specific to the outcome of delivery.

NOTE: The O80 to O84 codes are not used in the ICD-10-CA coding system from CIHI, and none of these codes are recorded in the MCHP Hospital Abstracts data (verified for April 1, 2004 to March 31, 2015 data on August 2, 2016).

MCHP captures the outcome of delivery by using ICD-10-CA codes beginning with "Z37" and additional CCI intervention codes.

Cautions / Notes

1. This concept focuses on the mother's / maternal outcome of delivery in hospital and does not include all the possible outcomes related to a pregnancy, such as abortion or ectopic pregnancy, or the birth outcomes related to the newborn child. For more information on these topics, please see the following:
   
   
   • Teenage Pregnancy / Teen Pregnancy concept - this concept includes a list of ICD and CCI codes for maternal outcomes of delivery, abortion and ectopic pregnancies, and delivery outcomes of a newborn child.
   
   
2. Births assisted by midwifes in a home location are not included in this methodology and represent a very small proportion of total births in Manitoba. In 2008/09, 3.9% of total births having a midwife as the provider occurred in a hospital, while 0.8% took place in a home setting (Heaman et al., 2012). In order to determine the outcome of delivery in this situation, several variables / indicators contained in the Midwifery Summary Report data, such as birth type, interventions and stillbirth, could be investigated to determine the outcome of delivery. Please see related variables in Appendix Table A.4: Table of Codes from Heaman et al. (2012) for more information on how this can be accomplished using the Midwifery Summary Report data.
   
   
3. There is some ongoing discussion over whether the "abstract type" = 3 is a required condition in the algorithm. Recent analysis into this situation revealed that when a V27 or Z37 diagnosis code was coded in the abstract, 99.9% of these abstracts were coded with an "abstract type" = 3, so a small percentage of outcomes may be missed over 30 years of data if "abstract type" = 3 is a required condition in the algorithm. The most important part of the algorithm is the diagnosis code(s) that identify the outcome of delivery.