You would have to talk to your healthcare provider for specific instructions (one who has had herbal training). In general though most expecting moms drink a few cups a day during the 2nd and/or 3rd trimesters.

If you want to! The white pithy part can sometimes taste bitter though.

Since these are nutritive herbs there’s a much wider safety range for dosing. Chamomile is already included in the recipe, but you could add a Tablespoon or two of each additional herb. Fennel has a strong licorice taste that would likely clash with the mint and the fruity tasting rosehips though.

You could just omit it.