During birth, your queen will "cry" and sound distressed, which is completely normal. You can expect to see a kitten every 10 to 60 minutes, and it's likely your cat will eat the placentas and chew through the kittens' umbilical cords. If two hours have passed after you've spotted the discharge and there's no sign of the newborns, get in touch with a vet who may need to assist the birth.
Cats are very good at looking after themselves during labor, so try to avoid fussing over her; checking on her every 15 minutes is perfectly fine. If she feels stressed in any way, she will interrupt her own labor and prevent delivery for hours, or even days!
The signs of a healthy newborn kitten
Once the kittens are delivered, they should immediately crawl toward their mother and start to suckle on her; keep kitten milk handy for any that don't. If your cat doesn't lick them after they've fed, you'll need to massage them with a damp compress to aid digestion and excretion. Keep the room quiet and warm, with the door closed—15-20% of cats who are new mothers come on heat within days of delivery and will wander off to find a mate, which can leave the kittens vulnerable.
A home birth for your pregnant cat can help her feel relaxed and stress-free, giving her litter the best start possible. If you're unsure about whether you've prepared your home in the right way, make sure to speak to your vet who will be able to advise you.