<?xml version="1.0" encoding="UTF-8"?>

<StructureDefinition xmlns="http://hl7.org/fhir">
  <id value="vn-ext-gestational-age"/>
  <language value="vi"/>
  <text>
    <status value="extensions"/><div xmlns="http://www.w3.org/1999/xhtml"><p class="res-header-id"><b>Generated Narrative: StructureDefinition vn-ext-gestational-age</b></p><a name="vn-ext-gestational-age"> </a><a name="hcvn-ext-gestational-age"> </a><table border="0" cellpadding="0" cellspacing="0" style="border: 0px #F0F0F0 solid; font-size: 11px; font-family: verdana; vertical-align: top;"><tr style="border: 1px #F0F0F0 solid; font-size: 11px; font-family: verdana; vertical-align: top"><th style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px" class="hierarchy"><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="The logical name of the element">Name</a></th><th style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px" class="hierarchy"><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Information about the use of the element">Flags</a></th><th style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px" class="hierarchy"><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Minimum and Maximum # of times the element can appear in the instance">Card.</a></th><th style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px; width: 100px" class="hierarchy"><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Reference to the type of the element">Type</a></th><th style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px" class="hierarchy"><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Additional information about the element">Description &amp; Constraints</a><span style="float: right"><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Legend for this format"><img src="data:image/png;base64,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" alt="doco" style="background-color: inherit"/></a></span></th></tr><tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white"><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck1.png)" class="hierarchy"><img src="tbl_spacer.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="icon_element.gif" alt="." style="background-color: white; background-color: inherit" title="Element" class="hierarchy"/> <a href="StructureDefinition-vn-ext-gestational-age-definitions.html#Extension" title="Tuần tuổi thai thực tế tại thời điểm thực hiện thủ thuật/ghi nhận trên giấy tờ KCB, tính bằng số nguyên tuần (1–42 tuần).
Mapping QĐ 3176/QĐ-BYT: TUOI_THAI (Bảng 7 STT 10 — Giấy ra viện; Bảng 11 STT 12 — Giấy chứng nhận nghỉ việc hưởng BHXH).
Trường TUOI_THAI bắt buộc theo điều kiện khi MA_DINH_CHI_THAI='1' (đình chỉ thai nghén). Quan hệ điều kiện này được ràng buộc ở tầng logical model qua invariant `bhyt-xml7-abortion-fields-required` (Bảng 7) và `bhyt-xml11-abortion-fields-required` (Bảng 11); extension chỉ mang giá trị số tuần, không tự enforce điều kiện bắt buộc.
Actual gestational age in whole weeks (1–42) at the time of the procedure or when recorded on the KCB document; FHIR R4 base has no gestational-age element on Procedure/DocumentReference.
Căn cứ: QĐ 3176/QĐ-BYT (29/10/2024).">Extension</a><a name="Extension"> </a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"/><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="opacity: 0.5">0</span><span style="opacity: 0.5">..</span><span style="opacity: 0.5">*</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><a href="http://hl7.org/fhir/R4/extensibility.html#Extension">Extension</a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy">Tuổi thai — Gestational Age Extension</td></tr>
<tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: #F7F7F7"><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck10.png)" class="hierarchy"><img src="tbl_spacer.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="tbl_vjoin.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="icon_extension_simple.png" alt="." style="background-color: #F7F7F7; background-color: inherit" title="Simple Extension" class="hierarchy"/> <a style="text-decoration:line-through; text-decoration:line-through" href="StructureDefinition-vn-ext-gestational-age-definitions.html#Extension.extension">extension</a><a name="Extension.extension"> </a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"/><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="text-decoration:line-through"/><span style="text-decoration:line-through">0</span><span style="text-decoration:line-through">..</span><span style="text-decoration:line-through">0</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"/><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="font-style: italic">Extension</span></td></tr>
<tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white"><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck10.png)" class="hierarchy"><img src="tbl_spacer.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="tbl_vjoin.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="icon_element.gif" alt="." style="background-color: white; background-color: inherit" title="Element" class="hierarchy"/> <a href="StructureDefinition-vn-ext-gestational-age-definitions.html#Extension.url">url</a><a name="Extension.url"> </a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"/><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="opacity: 0.5">1</span><span style="opacity: 0.5">..</span><span style="opacity: 0.5">1</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><a style="opacity: 0.5; opacity: 0.5" href="http://hl7.org/fhir/R4/datatypes.html#uri">uri</a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="color: darkgreen">&quot;http://fhir.hl7.org.vn/core/StructureDefinition/vn-ext-gestational-age&quot;</span></td></tr>
<tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: #F7F7F7"><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck00.png)" class="hierarchy"><img src="tbl_spacer.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="tbl_vjoin_end.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="icon_primitive.png" alt="." style="background-color: #F7F7F7; background-color: inherit" title="Primitive Data Type" class="hierarchy"/> <a href="StructureDefinition-vn-ext-gestational-age-definitions.html#Extension.value[x]" title="Số tuần tuổi thai thực tế (1–42 tuần) theo trường TUOI_THAI của QĐ 3176/QĐ-BYT (Bảng 7 STT 10, Bảng 11 STT 12). Bắt buộc theo điều kiện khi MA_DINH_CHI_THAI='1' — điều kiện được enforce bằng invariant `bhyt-xml7-abortion-fields-required` / `bhyt-xml11-abortion-fields-required` ở logical model, không phải bởi extension này.">value[x]</a><a name="Extension.value_x_"> </a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><a style="padding-left: 3px; padding-right: 3px; border: 1px maroon solid; font-weight: bold; color: #301212; background-color: #fdf4f4;; padding-left: 3px; padding-right: 3px; border: 1px maroon solid; font-weight: bold; color: #301212; background-color: #fdf4f4;" href="http://hl7.org/fhir/R4/conformance-rules.html#constraints" title="This element has or is affected by constraints ( vn-gestational-age-range )">C</a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy">1..<span style="opacity: 0.5">1</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><a href="http://hl7.org/fhir/R4/datatypes.html#integer">integer</a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy">Tuổi thai (tuần), 1–42 — TUOI_THAI<br class="constraint"/><span title="null" class="constraint">Constraints: </span><span style="font-weight:bold" title="Tuổi thai phải nằm trong khoảng 1–42 tuần theo QĐ 3176/QĐ-BYT (trường TUOI_THAI). Gestational age must be within 1–42 weeks." class="constraint">vn-gestational-age-range</span></td></tr>
<tr><td colspan="5" class="hierarchy"><br/><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Legend for this format"><img src="data:image/png;base64,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" alt="doco" style="background-color: inherit"/> Documentation for this format</a></td></tr></table></div>
  </text>
  <extension url="http://fhir.hl7.org.vn/core/StructureDefinition/vn-ext-legal-basis">
    <valueCoding>
      <system value="http://fhir.hl7.org.vn/core/CodeSystem/vn-legal-document-ref-cs"/>
      <code value="QD-3176-2024"/>
    </valueCoding>
  </extension>
  <url value="http://fhir.hl7.org.vn/core/StructureDefinition/vn-ext-gestational-age"/>
  <identifier>
    <system value="urn:ietf:rfc:3986"/>
    <value value="urn:oid:2.25.161089673617632664299011809196868855799.42.109"/>
  </identifier>
  <version value="0.8.0"/>
  <name value="VNCoreExtGestationalAge"/>
  <title value="Tuổi thai — Gestational Age Extension"/>
  <status value="draft"/>
  <date value="2026-07-10"/>
  <publisher value="Omi HealthTech / VN Core FHIR Community Initiative"/>
  <contact>
    <name value="Omi HealthTech / VN Core FHIR Community Initiative"/>
    <telecom>
      <system value="url"/>
      <value value="https://hl7.org.vn"/>
    </telecom>
    <telecom>
      <system value="email"/>
      <value value="info@hl7.org.vn"/>
    </telecom>
  </contact>
  <contact>
    <name value="Omi HealthTech (OmiGroup)"/>
    <telecom>
      <system value="url"/>
      <value value="https://omihealthtech.vn"/>
    </telecom>
    <telecom>
      <system value="url"/>
      <value value="https://omigroup.vn"/>
    </telecom>
    <telecom>
      <system value="email"/>
      <value value="info@hl7.org.vn"/>
    </telecom>
  </contact>
  <description value="Tuần tuổi thai thực tế tại thời điểm thực hiện thủ thuật/ghi nhận trên giấy tờ KCB, tính bằng số nguyên tuần (1–42 tuần).&#xA;Mapping QĐ 3176/QĐ-BYT: TUOI_THAI (Bảng 7 STT 10 — Giấy ra viện; Bảng 11 STT 12 — Giấy chứng nhận nghỉ việc hưởng BHXH).&#xA;Trường TUOI_THAI bắt buộc theo điều kiện khi MA_DINH_CHI_THAI='1' (đình chỉ thai nghén). Quan hệ điều kiện này được ràng buộc ở tầng logical model qua invariant `bhyt-xml7-abortion-fields-required` (Bảng 7) và `bhyt-xml11-abortion-fields-required` (Bảng 11); extension chỉ mang giá trị số tuần, không tự enforce điều kiện bắt buộc.&#xA;Actual gestational age in whole weeks (1–42) at the time of the procedure or when recorded on the KCB document; FHIR R4 base has no gestational-age element on Procedure/DocumentReference.&#xA;Căn cứ: QĐ 3176/QĐ-BYT (29/10/2024)."/>
  <jurisdiction>
    <coding>
      <system value="urn:iso:std:iso:3166"/>
      <code value="VN"/>
      <display value="Viet Nam"/>
    </coding>
  </jurisdiction>
  <fhirVersion value="4.0.1"/>
  <mapping>
    <identity value="rim"/>
    <uri value="http://hl7.org/v3"/>
    <name value="RIM Mapping"/>
  </mapping>
  <kind value="complex-type"/>
  <abstract value="false"/>
  <context>
    <type value="element"/>
    <expression value="Procedure"/>
  </context>
  <context>
    <type value="element"/>
    <expression value="DocumentReference"/>
  </context>
  <type value="Extension"/>
  <baseDefinition value="http://hl7.org/fhir/StructureDefinition/Extension"/>
  <derivation value="constraint"/>
  <snapshot>
    <extension url="http://hl7.org/fhir/tools/StructureDefinition/snapshot-base-version">
      <valueString value="4.0.1"/>
    </extension>
    <element id="Extension">
      <path value="Extension"/>
      <short value="Tuổi thai — Gestational Age Extension"/>
      <definition value="Tuần tuổi thai thực tế tại thời điểm thực hiện thủ thuật/ghi nhận trên giấy tờ KCB, tính bằng số nguyên tuần (1–42 tuần).&#xA;Mapping QĐ 3176/QĐ-BYT: TUOI_THAI (Bảng 7 STT 10 — Giấy ra viện; Bảng 11 STT 12 — Giấy chứng nhận nghỉ việc hưởng BHXH).&#xA;Trường TUOI_THAI bắt buộc theo điều kiện khi MA_DINH_CHI_THAI='1' (đình chỉ thai nghén). Quan hệ điều kiện này được ràng buộc ở tầng logical model qua invariant `bhyt-xml7-abortion-fields-required` (Bảng 7) và `bhyt-xml11-abortion-fields-required` (Bảng 11); extension chỉ mang giá trị số tuần, không tự enforce điều kiện bắt buộc.&#xA;Actual gestational age in whole weeks (1–42) at the time of the procedure or when recorded on the KCB document; FHIR R4 base has no gestational-age element on Procedure/DocumentReference.&#xA;Căn cứ: QĐ 3176/QĐ-BYT (29/10/2024)."/>
      <min value="0"/>
      <max value="*"/>
      <base>
        <path value="Extension"/>
        <min value="0"/>
        <max value="*"/>
      </base>
      <condition value="ele-1"/>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <constraint>
        <key value="ext-1"/>
        <severity value="error"/>
        <human value="Must have either extensions or value[x], not both"/>
        <expression value="extension.exists() != value.exists()"/>
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/>
      </constraint>
      <isModifier value="false"/>
    </element>
    <element id="Extension.id">
      <path value="Extension.id"/>
      <representation value="xmlAttr"/>
      <short value="Unique id for inter-element referencing"/>
      <definition value="Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="Element.id"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="string"/>
        </extension>
        <code value="http://hl7.org/fhirpath/System.String"/>
      </type>
      <isModifier value="false"/>
      <isSummary value="false"/>
      <mapping>
        <identity value="rim"/>
        <map value="n/a"/>
      </mapping>
    </element>
    <element id="Extension.extension">
      <path value="Extension.extension"/>
      <slicing>
        <discriminator>
          <type value="value"/>
          <path value="url"/>
        </discriminator>
        <description value="Extensions are always sliced by (at least) url"/>
        <rules value="open"/>
      </slicing>
      <short value="Extension"/>
      <definition value="An Extension"/>
      <min value="0"/>
      <max value="0"/>
      <base>
        <path value="Element.extension"/>
        <min value="0"/>
        <max value="*"/>
      </base>
      <type>
        <code value="Extension"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <constraint>
        <key value="ext-1"/>
        <severity value="error"/>
        <human value="Must have either extensions or value[x], not both"/>
        <expression value="extension.exists() != value.exists()"/>
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="false"/>
    </element>
    <element id="Extension.url">
      <path value="Extension.url"/>
      <representation value="xmlAttr"/>
      <short value="identifies the meaning of the extension"/>
      <definition value="Source of the definition for the extension code - a logical name or a URL."/>
      <comment value="The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension."/>
      <min value="1"/>
      <max value="1"/>
      <base>
        <path value="Extension.url"/>
        <min value="1"/>
        <max value="1"/>
      </base>
      <type>
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="uri"/>
        </extension>
        <code value="http://hl7.org/fhirpath/System.String"/>
      </type>
      <fixedUri value="http://fhir.hl7.org.vn/core/StructureDefinition/vn-ext-gestational-age"/>
      <isModifier value="false"/>
      <isSummary value="false"/>
      <mapping>
        <identity value="rim"/>
        <map value="N/A"/>
      </mapping>
    </element>
    <element id="Extension.value[x]">
      <path value="Extension.value[x]"/>
      <short value="Tuổi thai (tuần), 1–42 — TUOI_THAI"/>
      <definition value="Số tuần tuổi thai thực tế (1–42 tuần) theo trường TUOI_THAI của QĐ 3176/QĐ-BYT (Bảng 7 STT 10, Bảng 11 STT 12). Bắt buộc theo điều kiện khi MA_DINH_CHI_THAI='1' — điều kiện được enforce bằng invariant `bhyt-xml7-abortion-fields-required` / `bhyt-xml11-abortion-fields-required` ở logical model, không phải bởi extension này."/>
      <min value="1"/>
      <max value="1"/>
      <base>
        <path value="Extension.value[x]"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="integer"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <constraint>
        <key value="vn-gestational-age-range"/>
        <severity value="error"/>
        <human value="Tuổi thai phải nằm trong khoảng 1–42 tuần theo QĐ 3176/QĐ-BYT (trường TUOI_THAI). Gestational age must be within 1–42 weeks."/>
        <expression value="$this &gt;= 1 and $this &lt;= 42"/>
        <source value="http://fhir.hl7.org.vn/core/StructureDefinition/vn-ext-gestational-age"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="false"/>
      <mapping>
        <identity value="rim"/>
        <map value="N/A"/>
      </mapping>
    </element>
  </snapshot>
  <differential>
    <element id="Extension">
      <path value="Extension"/>
      <short value="Tuổi thai — Gestational Age Extension"/>
      <definition value="Tuần tuổi thai thực tế tại thời điểm thực hiện thủ thuật/ghi nhận trên giấy tờ KCB, tính bằng số nguyên tuần (1–42 tuần).&#xA;Mapping QĐ 3176/QĐ-BYT: TUOI_THAI (Bảng 7 STT 10 — Giấy ra viện; Bảng 11 STT 12 — Giấy chứng nhận nghỉ việc hưởng BHXH).&#xA;Trường TUOI_THAI bắt buộc theo điều kiện khi MA_DINH_CHI_THAI='1' (đình chỉ thai nghén). Quan hệ điều kiện này được ràng buộc ở tầng logical model qua invariant `bhyt-xml7-abortion-fields-required` (Bảng 7) và `bhyt-xml11-abortion-fields-required` (Bảng 11); extension chỉ mang giá trị số tuần, không tự enforce điều kiện bắt buộc.&#xA;Actual gestational age in whole weeks (1–42) at the time of the procedure or when recorded on the KCB document; FHIR R4 base has no gestational-age element on Procedure/DocumentReference.&#xA;Căn cứ: QĐ 3176/QĐ-BYT (29/10/2024)."/>
    </element>
    <element id="Extension.extension">
      <path value="Extension.extension"/>
      <max value="0"/>
    </element>
    <element id="Extension.url">
      <path value="Extension.url"/>
      <fixedUri value="http://fhir.hl7.org.vn/core/StructureDefinition/vn-ext-gestational-age"/>
    </element>
    <element id="Extension.value[x]">
      <path value="Extension.value[x]"/>
      <short value="Tuổi thai (tuần), 1–42 — TUOI_THAI"/>
      <definition value="Số tuần tuổi thai thực tế (1–42 tuần) theo trường TUOI_THAI của QĐ 3176/QĐ-BYT (Bảng 7 STT 10, Bảng 11 STT 12). Bắt buộc theo điều kiện khi MA_DINH_CHI_THAI='1' — điều kiện được enforce bằng invariant `bhyt-xml7-abortion-fields-required` / `bhyt-xml11-abortion-fields-required` ở logical model, không phải bởi extension này."/>
      <min value="1"/>
      <type>
        <code value="integer"/>
      </type>
      <constraint>
        <key value="vn-gestational-age-range"/>
        <severity value="error"/>
        <human value="Tuổi thai phải nằm trong khoảng 1–42 tuần theo QĐ 3176/QĐ-BYT (trường TUOI_THAI). Gestational age must be within 1–42 weeks."/>
        <expression value="$this &gt;= 1 and $this &lt;= 42"/>
        <source value="http://fhir.hl7.org.vn/core/StructureDefinition/vn-ext-gestational-age"/>
      </constraint>
    </element>
  </differential>
</StructureDefinition>