Melanie Cole 

I'm not sure this is possible.  Can you share the format of the PO file?  I imagine it's something like this:

msgid "An epidural anaesthetic involves injecting local anaesthetics and other painkillers into the epidural space (an area near your spinal cord). This numbs your nerves to give pain relief in certain areas of your body."
msgstr "Mae hyn yn rhwystro eich nerfau rhag teimlo dim er mwyn lleddfu’r boen mewn rhannau penodol o’ch corff."

msgid "Shared decision-making and informed consent"
msgstr "Gwneud penderfyniadau ar y cyd a chydsyniad ar sail gwybodaeth"

msgid "Your healthcare team have suggested an epidural anaesthetic. However, it is your decision to go ahead with the procedure or not. This document will give you information about the benefits and risks to help you make an informed decision."
msgstr "Mae eich tîm gofal iechyd wedi awgrymu anesthetig epidwral. Fodd bynnag, eich penderfyniad chi yw mynd ymlaen â’r driniaeth neu beidio. Mae’r ddogfen hon yn rhoi gwybodaeth i chi am y manteision a’r risgiau er mwyn eich helpu i wneud penderfyniad gwybodus."

So the paragraph is actually in the PO file itself, as opposed to this:

msgid "An epidural anaesthetic involves injecting local anaesthetics and other painkillers into the epidural space (an area near your spinal cord)."
msgstr ""

msgid "This numbs your nerves to give pain relief in certain areas of your body."
msgstr "Mae hyn yn rhwystro eich nerfau rhag teimlo dim er mwyn lleddfu’r boen mewn rhannau penodol o’ch corff."

msgid "Shared decision-making and informed consent"
msgstr "Gwneud penderfyniadau ar y cyd a chydsyniad ar sail gwybodaeth"

msgid "Your healthcare team have suggested an epidural anaesthetic. However, it is your decision to go ahead with the procedure or not. This document will give you information about the benefits and risks to help you make an informed decision."
msgstr "Mae eich tîm gofal iechyd wedi awgrymu anesthetig epidwral. Fodd bynnag, eich penderfyniad chi yw mynd ymlaen â’r driniaeth neu beidio. Mae’r ddogfen hon yn rhoi gwybodaeth i chi am y manteision a’r risgiau er mwyn eich helpu i wneud penderfyniad gwybodus."

Which would achieve what you need.

So unless you can show me the PO written in a way that would support such a segmentation I think you're stuck.  It would appear the same way in a PO editor for example:

There is a feature in the settings for the Trados Studio filetype that will do what you want if there is no target text at all yet, but once it's got a translation in there we don't support the segmentation.  Frankly I think we should and just put the target into the first segment if we can't segment that as well.  At least that way the translator could take responsibility for it... but we don't.  Perhaps a good idea for the ideas site.

So this:

msgid "An epidural anaesthetic involves injecting local anaesthetics and other painkillers into the epidural space (an area near your spinal cord). This numbs your nerves to give pain relief in certain areas of your body."
msgstr ""

msgid "Shared decision-making and informed consent"
msgstr "Gwneud penderfyniadau ar y cyd a chydsyniad ar sail gwybodaeth"

msgid "Your healthcare team have suggested an epidural anaesthetic. However, it is your decision to go ahead with the procedure or not. This document will give you information about the benefits and risks to help you make an informed decision."
msgstr "Mae eich tîm gofal iechyd wedi awgrymu anesthetig epidwral. Fodd bynnag, eich penderfyniad chi yw mynd ymlaen â’r driniaeth neu beidio. Mae’r ddogfen hon yn rhoi gwybodaeth i chi am y manteision a’r risgiau er mwyn eich helpu i wneud penderfyniad gwybodus."

Would get me this:

But then you'd have to remove all the target texts before you added to Studio and this isn't really practical.

Melanie Cole 

Incidentally... the AT is not Machine Translation.  It's the default for any translation coming from a PO file.  It just means "Automated Translation" in that the computer added it based on it already being in the file.

Thanks Paul, for both your answers. 

The PO files are formatted as per your first screenshot. Both sentences appear in the same string, which I guess is why it appears segmented this way. 

I have similar PO files which have not been pretranslated, and they appear segmented by sentence, so what you are saying makes sense.

It's a shame it doesn't apply to pretranslated files, is that for PO files only or other files too? I will pop it in the Ideas site. 

Melanie Cole 

Melanie Cole said:

It's a shame it doesn't apply to pretranslated files, is that for PO files only or other files too?

I'm pretty sure this logic applies to all bilingual source files.  So XLIFF, PO, Bilingual Excel etc.  The only exception I am aware of is the Multilingual Excel filetype that we developed in the appstore as we specifically ensured that this would be possible and just made it the responsibility of the translator to segment any target content that was there.

Melanie Cole 

There are a few attempts to handle bilingual file formats and overcome segmentation issues, but nothing is fire-and-forget or out of the box.

 RE: Custom bilingual XML with HTML embedded content 

 RE: xlf file segmentation in Trados Studio 2019 

Maybe you find something there that helps you.