How much formula?

[plibble]

My DD is 21 weeks and will be starting nursery soon. I plan to give her breastmilk once or twice a day (before and/or after nursery) but she will be on formula at nursery as I can't express enough for her to have breastmilk. I guess she will need 3 bottles during the day. How do I work out how much formula she needs?

Also, to start with she will be attending nursery on Mondays only. Is it possible that I could maintain my milk supply and b/f her on the other days, while giving 3 formula feeds when she's at nursery?

Thanks for your help- I have got so used to the convenience of breastfeeding that anything else seems utterly confusing!

I weaned ds onto mixed feedign at 6 months ish . he had b'feeds in the morning and evening and 8oz mid morning and mid afternoon with a "lunch" between. Can't you just leave 3 8oz bottles and see what she takes ?

Thanks. I must be very dim tonight - it never occurred to me to just leave lots!