Can I also add that the only pregnant females that we will put forward for council accommodation sharpish (providing they're not intentionally homeless and meet all other criteria) are girls who are care leavers aged 18-21.
Many will probably disagree with this, but of all the extremely vulnerable people I come across, care leavers are right at the top. Some of the pregnant care leavers I've seen, despite their young age, have experienced more horrors in life than you can imagine.
Ultimately, you have to think about whether it is kinder for all involved to place them into secure accommodation and at least give them an opportunity to raise their child despite the difficulties and lack of stability they have experienced in their own childhoods, or whether you react as many posters on here would and essentially tell them to clear off.
It is frustrating when people act 'fecklessly', but there are children involved in these situations who have not asked or done anything to deserve being treated with such contempt.
What do you do if you don't 'give them' a house? Let them rot on the street? Take their child into care?
The only way to overcome these difficulties is to ensure that young girls, as much as possible, are educated to understand that they do have other options and that having a child is not an automatic way to make life more fulfilling and secure.