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Product of conception—gestational age, completed weeks N[N]

Identifying and definitional attributes

Metadata item type:Help on this termData Element
Short name:Help on this termGestational age
METeOR identifier:Help on this term298105
Registration status:Help on this termHealth, Superseded 02/08/2017
Tasmanian Health, Endorsed 20/12/2016
Definition:Help on this term

The age of a product of conception in completed weeks.

Data Element Concept:Product of conception—gestational age

Value domain attributes

Representational attributes

Representation class:Help on this termTotal
Data type:Help on this termNumber
Format:Help on this termN[N]
Maximum character length:Help on this term2
Supplementary values:Help on this term
ValueMeaning
99Not stated/unknown
Unit of measure:Help on this termCompleted weeks

Data element attributes

Collection and usage attributes

Guide for use:Help on this term

Gestational age is the best clinical estimate of the duration of pregnancy at a specific point in time, based on the first day of the last menstrual period, ultrasound or physical examination of the baby.

Gestational age is conventionally expressed in completed weeks. When gestational age is calculated using the first day of the last normal menstrual period, the first day is counted as day zero and not day one. Therefore, a 25 week, 5 day fetus is considered a 25 week fetus (25+0, 25+1, 25+2, 25+3, 25+4, 25+5, 25+6).

When ultrasound is used to date a pregnancy, the earliest ultrasound examination should be used and should preferably be between 6 and 10 weeks gestation. Scans performed beyond 24 weeks gestation are unlikely to be reliable in estimating gestational age and should not be used for this purpose.

The duration of gestation can be determined from the first day of the last normal menstrual period, from ultrasound or clinical assessment. For the purpose of the national collection, gestational age is expressed in completed weeks.

The World Health Organization identifies the following categories:

  • pre-term: less than 37 completed weeks (less than 259 days) of gestation;
  • term: from 37 completed weeks to less than 42 completed weeks (259 to 293 days) of gestation; and
  • post-term: 42 completed weeks or more (294 days or more) of gestation.
Comments:Help on this term

Gestational age is a key marker in pregnancy and an important risk factor for neonatal outcomes.

Source and reference attributes

Submitting organisation:Help on this term

National Perinatal Data Development Committee

Origin:Help on this term

International Classification of Diseases and Related Health Problems, 10 Revision, WHO, 1992

Reference documents:Help on this term

American Academy of Pediatrics 2004. Policy statement Age terminology during the perinatal period. Paediatrics 114:5 November.

Relational attributes

Related metadata references:Help on this term

Supersedes Female (pregnant)—estimated gestational age, total weeks NN Health, Superseded 02/12/2009

See also Pregnancy—estimated duration (at the first visit for antenatal care), completed weeks N[N] Health, Superseded 02/08/2017, Tasmanian Health, Endorsed 20/12/2016, Indigenous, Archived 22/10/2018

See also Pregnancy—estimated duration, total weeks N[N] WA Health, Endorsed 04/03/2014

Has been superseded by Product of conception—gestational age, completed weeks N[N] Health, Superseded 12/12/2018, ACT Health, Final 14/08/2018

Implementation in Data Set Specifications:Help on this term
All attributes +

Perinatal NMDS 2010-2011 Health, Superseded 21/12/2010

DSS specific attributes +

Perinatal NMDS 2011-12 Health, Superseded 07/03/2012

DSS specific attributes +

Perinatal NMDS 2012-13 Health, Superseded 07/02/2013

DSS specific attributes +

Perinatal NMDS 2013-14 Health, Superseded 07/03/2014

DSS specific attributes +

Perinatal NMDS 2014-18 Health, Superseded 02/08/2017

DSS specific attributes +

Tasmanian Perinatal Data Set - 2016 Tasmanian Health, Endorsed 30/01/2017

DSS specific attributes +
Implementation in Indicators:Help on this termUsed as numerator
Australian Atlas of Healthcare Variation: Caesarean section for selected women giving birth for the first time, 2012-2014 Australian Commission on Safety and Quality in Health Care, Standard 07/06/2017
National Core Maternity Indicators: PI 04-Apgar score of less than 7 at 5 minutes for births at or after term (2013) Health, Superseded 02/02/2016
National Core Maternity Indicators: PI 04–Apgar score of less than 7 at 5 minutes for births at or after term, 2018 Health, Superseded 19/06/2019
National Core Maternity Indicators: PI 04–Apgar score of less than 7 at 5 minutes for births at or after term, 2019 Health, Standard 19/06/2019
National Core Maternity Indicators: PI 04—Apgar score of less than 7 at 5 minutes for births at or after term (2016) Health, Superseded 06/09/2018
National Core Maternity Indicators: PI 05-Induction of labour for selected women giving birth for the first time (2013) Health, Superseded 02/02/2016
National Core Maternity Indicators: PI 05–Induction of labour for selected females giving birth for the first time, 2018 Health, Superseded 19/06/2019
National Core Maternity Indicators: PI 05–Induction of labour for selected females giving birth for the first time, 2019 Health, Standard 19/06/2019
National Core Maternity Indicators: PI 05—Induction of labour for selected women giving birth for the first time (2016) Health, Superseded 06/09/2018
National Core Maternity Indicators: PI 06-Caesarean section for selected women giving birth for the first time (2013) Health, Superseded 02/02/2016
National Core Maternity Indicators: PI 06–Caesarean section for selected females giving birth for the first time, 2018 Health, Superseded 19/06/2019
National Core Maternity Indicators: PI 06–Caesarean section for selected females giving birth for the first time, 2019 Health, Standard 19/06/2019
National Core Maternity Indicators: PI 06—Caesarean section for selected women giving birth for the first time (2016) Health, Superseded 06/09/2018
National Core Maternity Indicators: PI 07-Normal (non-instrumental) vaginal birth for selected women giving birth for the first time (2013) Health, Superseded 02/02/2016
National Core Maternity Indicators: PI 07–Non-instrumental vaginal birth for selected females giving birth for the first time, 2018 Health, Superseded 19/06/2019
National Core Maternity Indicators: PI 07–Non-instrumental vaginal birth for selected females giving birth for the first time, 2019 Health, Standard 19/06/2019
National Core Maternity Indicators: PI 07—Normal (non-instrumental) vaginal birth for selected women giving birth for the first time (2016) Health, Superseded 06/09/2018
National Core Maternity Indicators: PI 08-Instrumental vaginal birth for selected women giving birth for the first time (2013) Health, Superseded 02/02/2016
National Core Maternity Indicators: PI 08–Instrumental vaginal birth for selected females giving birth for the first time, 2018 Health, Superseded 19/06/2019
National Core Maternity Indicators: PI 08–Instrumental vaginal birth for selected females giving birth for the first time, 2019 Health, Standard 19/06/2019
National Core Maternity Indicators: PI 08—Instrumental vaginal birth for selected women giving birth for the first time (2016) Health, Superseded 06/09/2018
National Core Maternity Indicators: PI 10-Small babies among births at or after 40 weeks gestation (2013) Health, Superseded 02/02/2016
National Core Maternity Indicators: PI 10–Small babies among births at or after 40 weeks gestation, 2018 Health, Superseded 19/06/2019
National Core Maternity Indicators: PI 10–Small babies among births at or after 40 weeks gestation, 2019 Health, Standard 19/06/2019
National Core Maternity Indicators: PI 10—Small babies among births at or after 40 weeks gestation (2016) Health, Superseded 06/09/2018
National Healthcare Agreement: PI 01–Proportion of babies born of low birth weight, 2017 Health, Superseded 30/01/2018
National Healthcare Agreement: PI 01–Proportion of babies born of low birth weight, 2018 Health, Superseded 19/06/2019
National Healthcare Agreement: PI 01–Proportion of babies born of low birth weight, 2019 Health, Standard 19/06/2019
National Indigenous Reform Agreement: PI 09-Antenatal care, 2018 Indigenous, Archived 31/07/2018
National Indigenous Reform Agreement: PI 09-Antenatal care, 2019 Indigenous, Archived 23/08/2019
National Indigenous Reform Agreement: PI 09-Antenatal care, 2020 Indigenous, Endorsed 23/08/2019
National Indigenous Reform Agreement: PI 09—Antenatal care, 2016 Indigenous, Archived 01/07/2016
National Indigenous Reform Agreement: PI 09—Antenatal care, 2017 Indigenous, Archived 06/06/2017
Used as denominator
Australian Atlas of Healthcare Variation 2018: Caesarean section at less than (i) 39 completed weeks, (ii) 37 completed weeks without medical/obstetric indication, 2015 Australian Commission on Safety and Quality in Health Care, Standard 13/12/2018
National Core Maternity Indicators: PI 04-Apgar score of less than 7 at 5 minutes for births at or after term (2013) Health, Superseded 02/02/2016
National Core Maternity Indicators: PI 04–Apgar score of less than 7 at 5 minutes for births at or after term, 2018 Health, Superseded 19/06/2019
National Core Maternity Indicators: PI 04–Apgar score of less than 7 at 5 minutes for births at or after term, 2019 Health, Standard 19/06/2019
National Core Maternity Indicators: PI 04—Apgar score of less than 7 at 5 minutes for births at or after term (2016) Health, Superseded 06/09/2018
National Core Maternity Indicators: PI 05-Induction of labour for selected women giving birth for the first time (2013) Health, Superseded 02/02/2016
National Core Maternity Indicators: PI 05–Induction of labour for selected females giving birth for the first time, 2018 Health, Superseded 19/06/2019
National Core Maternity Indicators: PI 05–Induction of labour for selected females giving birth for the first time, 2019 Health, Standard 19/06/2019
National Core Maternity Indicators: PI 05—Induction of labour for selected women giving birth for the first time (2016) Health, Superseded 06/09/2018
National Core Maternity Indicators: PI 06–Caesarean section for selected females giving birth for the first time, 2018 Health, Superseded 19/06/2019
National Core Maternity Indicators: PI 06–Caesarean section for selected females giving birth for the first time, 2019 Health, Standard 19/06/2019
National Core Maternity Indicators: PI 06—Caesarean section for selected women giving birth for the first time (2016) Health, Superseded 06/09/2018
National Core Maternity Indicators: PI 07–Non-instrumental vaginal birth for selected females giving birth for the first time, 2018 Health, Superseded 19/06/2019
National Core Maternity Indicators: PI 07–Non-instrumental vaginal birth for selected females giving birth for the first time, 2019 Health, Standard 19/06/2019
National Core Maternity Indicators: PI 07—Normal (non-instrumental) vaginal birth for selected women giving birth for the first time (2016) Health, Superseded 06/09/2018
National Core Maternity Indicators: PI 08–Instrumental vaginal birth for selected females giving birth for the first time, 2018 Health, Superseded 19/06/2019
National Core Maternity Indicators: PI 08–Instrumental vaginal birth for selected females giving birth for the first time, 2019 Health, Standard 19/06/2019
National Core Maternity Indicators: PI 08—Instrumental vaginal birth for selected women giving birth for the first time (2016) Health, Superseded 06/09/2018
National Core Maternity Indicators: PI 10-Small babies among births at or after 40 weeks gestation (2013) Health, Superseded 02/02/2016
National Core Maternity Indicators: PI 10–Small babies among births at or after 40 weeks gestation, 2018 Health, Superseded 19/06/2019
National Core Maternity Indicators: PI 10–Small babies among births at or after 40 weeks gestation, 2019 Health, Standard 19/06/2019
National Core Maternity Indicators: PI 10—Small babies among births at or after 40 weeks gestation (2016) Health, Superseded 06/09/2018
National Healthcare Agreement: PI 01–Proportion of babies born of low birth weight, 2017 Health, Superseded 30/01/2018
National Healthcare Agreement: PI 01–Proportion of babies born of low birth weight, 2018 Health, Superseded 19/06/2019
National Healthcare Agreement: PI 01–Proportion of babies born of low birth weight, 2019 Health, Standard 19/06/2019
National Indigenous Reform Agreement: PI 07-Proportion of babies born of low birthweight, 2018 Indigenous, Archived 31/07/2018
National Indigenous Reform Agreement: PI 07-Proportion of babies born of low birthweight, 2019 Indigenous, Archived 23/08/2019
National Indigenous Reform Agreement: PI 07-Proportion of babies born of low birthweight, 2020 Indigenous, Endorsed 23/08/2019
National Indigenous Reform Agreement: PI 07—Proportion of babies born of low birthweight, 2017 Indigenous, Archived 06/06/2017
National Indigenous Reform Agreement: PI 09-Antenatal care, 2018 Indigenous, Archived 31/07/2018
National Indigenous Reform Agreement: PI 09-Antenatal care, 2019 Indigenous, Archived 23/08/2019
National Indigenous Reform Agreement: PI 09-Antenatal care, 2020 Indigenous, Endorsed 23/08/2019
National Indigenous Reform Agreement: PI 09—Antenatal care, 2016 Indigenous, Archived 01/07/2016
National Indigenous Reform Agreement: PI 09—Antenatal care, 2017 Indigenous, Archived 06/06/2017
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