The subject of that observation - Is it normally / better the child or mother?

mother is the one pregnant

how do I say which prenancy?

there's more than one?

Observation would need to say "for this child's pregnancy, the duration was 40 weeks"

oh, sorry, i was thinking the pregnancy was ongoing

this is in a report for a single child, but if information will be fetched from the mother's record, i think I need to consider that

what's the LOINC code?

we don't have one yet, i am waiting for a code, will most likely get a snomed one

from the notes I took, this would need to be validated with clinical people, I don't know what is common. I would be happy to say it is an observation of the child, but i may just be lazy

My note was "we will require the link between child and mother, or even link between child - pregnancy - mother"

in the rest of the document, the subject is the child and the mother may appear as a relatedPerson. For these I am doubting - PregnancyCMVInfection, PregnancyDuration, PregnancyBacterialMeningitis

well, for me it depends on how the code is expressed, but LOINC 18185-9 Gestational age is: The age of the conceptus, beginning from the time of fertilization. In clinical obstetrics, the gestational age is often estimated as the time from the last day of the last menstruation which is about 2 weeks before ovulation and fertilization.Source: National Library of Medicine, MeSH 2006 so that'd make the child / individual the focus

Do you have more context? In general, after the baby is born, clinicians seeing the child would consider duration of pregnancy to be connected to the child. Or at least, that is how neonatologists and paediatricians think and talk. Clinically, I would generally consider the duration of any prior pregnancies, related to the mother, as I am seeing them as a patient. This is true for obstetric contexts (e.g. medical decision making and planning for new pregnancy would be informed by duration of prior pregnancies) and gynaecologic contexts (e.g. post menopausal patient and risk stratification for possible endometrial pathology). I think most people involved in obstetric care / women's health would think this way. But when you are talking about the duration of pregnancy for a current pregnancy, it is really unclear who the subject is... it is surprisingly fuzzy and I don't know if there is a clear answer. I think the maternal/fetal dyad deserves its own data paradigm and mental model. There is an HL7 working group calle d CHOICE (child health & obstetrics international collaboration and exploration) who have done some good data modelling on this. I am not part of it, but @Lilian Minne , @Rob Hausam , and @Stephen Chu are names from CHOICE who I have seen on this forum, so maybe they can weigh in.

context: this is for child follow-up - the recommended hearing tests, eye tests...

we have the following elements:

durationOfPregnancy pregnancyCMVInfection bacterialMeningitis

i think they are all "conditions" of the mother, but what we care about is "did child have antepartum exposure to maternal CMV infection / meningitis."

Hi @Jose Costa Teixeira we had a lot of discussion on this topic in our working group. There is some overlap in data that is relevant to both the health of the child as well as the health of the mother. For example, we believe the child is the subject of the Apgar score, but it should also be part of the medical record of the mother since it is also relevant for her health and her next pregnancies. So we think this Observation should be linked to both the child and the mother record. In the CHOICE project we focused mainly on fetal data, where we have a third subject: the unborn child (or fetus). There are cases where you want to be very specific on the subject, for example a medication administration that is meant for the fetus and not the mother. Maybe @Michael Padula could add to this from a clinical perspective.

thanks @Lilian Minne so, in FHIR Observations, how would this be associated with both child and mother?

I would guess it's safer to duplicate the data and not try to connect mother and child (or any other two patients) on a clinical data level. In case mother closes her data, the same data for the child should remain open. In case the child is placed for an adoption, the observations stay relevant for both, but the connection between people must not be visible to anyone.

I am ok with duplicating the data somehow, i do need to know who is the subject of such an observation, if it is the same code, etc.

Subject is the person who's record it is in, so I think it has to be the infant is the subject, mother (relatedPerson) is the focus.

That makes sense, thank you

Revisiting this - I don't feel comfortable with the approach for .focus here

reason: if mother has an infection, then I would expect to have one same observation (or actually Condition which doesn't have focus), and I could use it in both records, right?

Is the expectation that I duplicate the information for each child's record? it is exactly the same infection

or perhaps best to have an Observation as a "token" that points to the mother's Condition? Meaning something like "we note that this patient was exposed to a maternal CMV infection -but we don't detail that here"

From recollection during CHOICE project discussions, we landed on the following: During pregnancy there is one set of record - the record of the pregnant woman, which also contain data about the fetus (or fetuses). There are circumstances in which record(s) would be created for the fetus (or fetuses) during pregnancy, e.g. open surgery or fetoscopic surgery. For the purpose of this discussion, let us consider the use case of a single record - i.e. a record of the pregnant woman which include data about the fetus. After birth of the baby, there will be 2 separate records - one for the mother and one for the newborn | baby | child (following the development pathway) Let us also consider this use case: Woman diagnosed with CMV infection during pregnancy. Documenting diagnostic test findings: Pregnant woman: serology tests (IgG, IgM ...) Observation.subject = pregnant woman Fetus: Amniotic fluid to detect CMV DNA Cordocentesis - fetal blood for CMV IgM ... Observation.subject = pregnant woman Observation.focus Reference(RelatedPerson) Documenting CMV infection as a condition (confirmed by diagnostic tests) Condition resource does not have .focus Condition.subject 1..1 Reference ( Patient | Group ) Group.member 0..* Group.member.entity 1..1 Reference ( CareTeam | Device | Group | HealthcareService | Location | Organization | Patient | Practitioner | PractitionerRole | RelatedPerson | Specimen | Medication | MedicinalProductDefinition | Substance | SubstanceDefinition | BiologicallyDerivedProduct | NutritionProduct ) Group.member.entity - Patient -> describes the mother (CMV infection) Group.member.entity - RelatedPerson -> describes the fetus (CMV affecting the fetus)