http://hl7.org/fhir/StructureDefinition/patient-multipleBirthTotal|5.2.0

Where a patient is a part of a multiple birth, this is the total number of births that occurred in this pregnancy. This includes all live births and all fetal losses.\r\rWhen the patients have not been born yet, this is the total number of fetuses that are known to be present.\r\rThis value is the 4 in '3 of *4*', and the 3 would be the Patient.multipleBirth value.
{
  "description": "Where a patient is a part of a multiple birth, this is the total number of births that occurred in this pregnancy. This includes all live births and all fetal losses.\\r\\rWhen the patients have not been born yet, this is the total number of fetuses that are known to be present.\\r\\rThis value is the 4 in '3 of *4*', and the 3 would be the Patient.multipleBirth value.",
  "package": "hl7.fhir.uv.extensions@5.2.0",
  "date": "2020-12-28T05:55:11Z",
  "derivation": "constraint",
  "publisher": "HL7 International / Patient Administration",
  "fhirVersion": "5.0.0",
  "jurisdiction": [ {
    "coding": [ {
      "code": "001",
      "system": "http://unstats.un.org/unsd/methods/m49/m49.htm"
    } ]
  } ],
  "name": "PatMultipleBirthTotal",
  "mapping": [ {
    "uri": "http://hl7.org/v3",
    "name": "RIM Mapping",
    "identity": "rim"
  } ],
  "abstract": false,
  "type": "Extension",
  "experimental": false,
  "resourceType": "StructureDefinition",
  "fhirversion": null,
  "title": "Patient Multiple Birth Total",
  "versionAlgorithmCoding": null,
  "extension": [ {
    "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-wg",
    "valueCode": "pa"
  }, {
    "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm",
    "valueInteger": 2
  }, {
    "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status",
    "valueCode": "trial-use"
  }, {
    "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-type-characteristics",
    "valueCode": "can-bind"
  } ],
  "status": "draft",
  "id": "425dafdf-317a-5fff-b525-83244529b4aa",
  "kind": "complex-type",
  "url": "http://hl7.org/fhir/StructureDefinition/patient-multipleBirthTotal",
  "identifier": [ {
    "value": "urn:oid:2.16.840.1.113883.4.642.5.1328",
    "system": "urn:ietf:rfc:3986"
  } ],
  "context": [ {
    "type": "element",
    "expression": "Patient.multipleBirth[x]"
  } ],
  "versionAlgorithmString": null,
  "fhir_id": null,
  "version": "5.2.0",
  "contact": [ {
    "telecom": [ {
      "value": "http://www.hl7.org/Special/committees/pafm",
      "system": "url"
    } ]
  } ],
  "baseDefinition": "http://hl7.org/fhir/StructureDefinition/Extension"
}