description: This profile represents the date of the last menstrual period of the patient. The first day of last menstrual period should be captured. The effectiveDateTime captures the observation date. package_name: hl7.fhir.us.bfdr.r4b derivation: constraint name: ObservationLastMenstrualPeriod type: Observation elements: code: short: Last menstrual period start date pattern: type: CodeableConcept value: coding: - {code: 8665-2, system: 'http://loinc.org'} index: 0 subject: type: Reference refers: ['http://hl7.org/fhir/us/vr-common-library/StructureDefinition/Patient-mother-vr'] index: 1 effective: short: Observation date (date on which the observation was reported to the provider). choices: [effectiveDateTime] index: 3 effectiveDateTime: {type: dateTime, short: Observation date (date on which the observation was reported to the provider)., choiceOf: effective, index: 4} value: short: Start of last menstrual period choices: [valueDateTime] index: 6 valueDateTime: {type: dateTime, short: Start of last menstrual period, choiceOf: value, index: 7} package_version: 2.0.0 class: profile kind: resource url: http://hl7.org/fhir/us/bfdr/StructureDefinition/Observation-last-menstrual-period base: http://hl7.org/fhir/StructureDefinition/Observation version: 2.0.0 required: [valueDateTime, value, subject]