Realistically it's going to increase the time it takes to pay off the debts. Having a child is a speedbump in terms of finances. And as you've said you won't have as much money to spend on baby stuff. It will be tough but it's not the end of the world. Babies don't need lots of stuff, and what they "deserve" is really your love and attention, not the most high rated pram or whatever.
You can get so much second hand as well - keep an eye out for NCT nearly new sales, and join a facebook selling group (even if you "unfollow") but this is what babies really need:
Somewhere to sleep - can find second hand plus Ikea/amazon mattress for £20. Or new Ikea cot for £39. Second hand sheets or cheap on amazon. Blanket/baby sleeping bag again cheap second hand.
Car seat - Joie Juva is a cheap one from birth-1 year and will go in any car. If you'd prefer one which lasts longer the Joie Tilt will last until about 3.5 but is less convenient as stays in the car.
Way to transport - you can pick up a second hand pushchair very cheaply. Don't buy the first thing you see. Have a look at a few and pick something up later in the pregnancy.
Clothes - again VERY cheap second hand, supermarkets, etc.
Nappies and formula you'll have to buy, if you use these. You can get cloth nappies cheaper sometimes and some councils offer cashback. If breastfeeding, breast pads and a couple of nursing bras.
That's about it? You don't NEED anything else - they are all nice to have. You can bath the baby in the sink until it can sit up in the bath. Use towels and washcloths you already have. They aren't interested in toys and books until later and when they are - charity shop, sales, amazon, facebook, ebay.