Which is correct:
The patient is 39 weeks 5 days of gestation.
The patient is 39 weeks and 5 days of gestation.
Which is correct in the possessive situation ("of" is not needed as an apostrophe is used in its place)
The patient is 39 weeks and 5 days' gestation.
The patient is 39 weeks 5 days' gestation.
The patient is 39 weeks' and 5 days' gestation.
I am a medical transcriptionist and we have been struggling with this for a long time and need clear definition.
Thanks for the reply, but you stated that an apostrophe is not necessary, but isn't it necessary in the examples where "...5 days' gestation" is used. The apostrophe actually replaces the word "of" and it is a possessive-type situation. If you are saying 39 weeks 5 days of gestation, no apostrophe is needed; but rather 39 weeks and 5 days' gestation, then an apostrophe would be necessary--I'm thinking that is correct???
It is necessary if you mean the gestation time belonging to the period, or constituted by the period. So if you are thinking along those lines, then to express your thought explicitly you need the apostrophe.
But you can take a similar yet different approach to the concepts, and use the time period's length declaratively as a sort of metaphor, a stretching of the truth in a manner of speaking, for its own end point.
Shakespeare did this -- "the two hours' traffick of our stage...."
But if you really think about it, the real stretch, or metaphor, is saying that the patient IS the gestation period, rather than saying she is AT that period of her gestation. Before I clicked on your profile, I thought you might be a French speaker, for thinking in the rigorous way you did about this; indeed the French say things like "We are Tuesday, are we not?"
Personally, I would say
The patient's at 39 weeks 5 days in her pregnancy [or 'gestation'.]
[Note to self: don't type out answers to people when you're digesting; you're splitting hairs, and are generally off your head.]