HG till 7 months with DD. Took me 4 years and an assurance from Ob consultant that it was unlikely to happen again to continue with my pg with DS1. HG so severe I spent 19 weeks out of 40 on a drip in hospital!
Swore I would never have any more.
18 months later, I fell pg again (despite birth control). Almost had a termination, but couldn't go through with it. Had HG all the way through, though not as bad as with DS1, only spent 6 weeks in hospital.
Yet again, swore I'd not have any more. Though still couldn't be sterilised due to my age.
After a 7 year gap, I fell pg with DS4. Yet again, HG. Again, right up until I gave birth.
Have been on meds for HG for all 4 pregnancies. Metaclopramide was the most successful for me, though with DS1 I ended up on stemetil suppositories as I couldn't keep water down to swallow pills.
Now? I'm getting sterilised in October (finally old enough, had DD at 16 though, so have had a long wait to my 30's!)
Could NOT go through it again. Sorry if that's not what you wanted to hear!