Observations

"The estimated gestational age (in weeks, or weeks and fraction of week) of the pregnancy at the time of the health care encounter (in contrast to the gestational age at birth), beginning from the time of fertilization. Needs to be correlated with the date the gestational age was documented.
Gestational age (written with both weeks and days) is calculated using the best obstetrical estimated delivery date (EDD) based on the following formula: Gestational Age = (280 - (EDD - Reference Date))/ 7"

Submitted By: Nedra Garrett / Centers for Disease Control and Prevention
Data Element Information
Use Case Description(s)
Use Case Description	The data elements above are based on commonly used terms across the industry. Many of these data elements are captured in maternity EHRs, are defined and endorsed by the American College of Obstetricians and Gynecologists (ACOG)2, and are represented in LOINC with Class=”OB.US/clinical”.
Estimated number of stakeholders capturing, accessing using or exchanging	There are a large number of stakeholders, e.g., federal researchers and scientists, federal, state and local public health professionals, university-based researchers, clincians, health system administrators, private and public providers of health insurance, public and private-sector developers of new therapies and technologies.
Link to use case project page	https://www.hl7.org/special/Committees/projman/searchableProjectIndex.cfm?action=edit&ProjectNumber=1398
Healthcare Aims	Improving patient experience of care (quality and/or satisfaction) Improving the health of populations Improving provider experience of care
Maturity of Use and Technical Specifications for Data Element
Applicable Standard(s)	https://www.hl7.org/implement/standards/product_brief.cfm?product_id=494 https://www.hl7.org/implement/standards/product_brief.cfm?product_id=494
Additional Specifications	https://www.hl7.org/implement/standards/product_brief.cfm?product_id=494
Current Use	Extensively used in production environments
Supporting Artifacts	https://www.hl7.org/special/Committees/projman/searchableProjectIndex.cfm?action=edit&ProjectNumber=1399 CDAR2_IG_PREGNANCY_R1_DSTU_2019JAN.pdf
Number of organizations/individuals with which this data element has been electronically exchanged	N/A
Potential Challenges
Restrictions on Standardization (e.g. proprietary code)	We are not aware of restrictions.
Restrictions on Use (e.g. licensing, user fees)	We are not aware of restrictions.
Privacy and Security Concerns	Pregnancy-related data, particularly pregnancy outcome, is sensitive and private information. It will be important to safeguard identifying information of individuals using current HIPAA standards.
Estimate of Overall Burden	N/A
Other Implementation Challenges	N/A