@pallisers
I wouldn't wish that on someone of 19. I want my children to live a little before the most demanding and important relationship of their lives takes over.
I also would not want my 19 year old to have a baby with a young man she has been dating from the age of 15. Way too young. you change a lot after the age of 15. the boy you loved then might be a lovely person but might not be the one you want to be connected to for the rest of your life (as you will if you have a baby with him).
Yes I know so many Mumsnetters have had mortgages and houses and pets and dogs and jobs and degrees and husbands and children at age 19 and are still blissfully in love and visiting foreign countries 20 years later.
But the reality is most teenage relationships where they have a baby aren't this rosy-looking. And it is highly unlikely the OP's dd would be like this given they can't even rent their own place at the moment. If I were her mother I would be worried she is wondering what next and sees having a baby as the next thing without actually thinking about her life and what might happen.
So if it were my dd, yes I would discourage.
Brilliant post. Put so much better than I could put it. Very very true too. It is far more likely they will end up as a single mother living in penury, than this far-fetched rosy wonderful life SOME make out they have, after having babies in their teens.
And the upshot is, a few people on here are basically saying if you don't have your kids before 20, and get on the property ladder, you will end up an STD riddled old hag, who will be never get on the property ladder, and even if you do, you'll be on it til you die of old age, and loneliness, and it will serve you right for not getting tied down at 19.
And other people are saying if you have kids in your teens there will be much less likelihood of 'custody battles' and you will be more likely to get on with your ex. WTAF?! Are people on here actually looking at what they've typed before they hit 'submit.??? 
And it seems if you don't agree with certain posters advocating getting tied down in your teens, you are judgemental and horrible, and they hope YOUR kids don't turn out like you, or get pregnant in their teens! Newsflash, mine are both early to mid 20's, both post graduates, both well-travelled, both in successful well-paid careers, both have boyfriends they have lived with for a year or so, and both have no INTENTION of having kids for at LEAST 5 years. Sorry to disappoint you.
I see quite a few people here getting arsey and snarky with people saying it's a bad idea to settle down and have a baby at 18-19, and thinking it's a terrible idea to get a mortgage at that age too. I wonder why they are so upset and angry at peoples views. Surely if you're happy with your life choices, you wouldn't care? 
Some of the posts on here are batshit, and I think it's a joke that so many people on here are supporting someone barely out of childhood getting tied down with kids and a mortgage at 17-19. No WAY can anyone seriously think it's a good idea, and no WAY would they be OK with their daughter or son doing it. No WAY. I'm not having it. 
If I knew someone in real life who was encouraging their teenager to have a baby, and take on a mortgage with a lad they have known 3 years (since they were 16,) I'd be disgusted with them, and frankly, I'd think they were pretty poor parents.
@ohmydayslove
I agree. People using their own personal circumstances as ammo to attack other people is disgusting.