Wait. Pumpkins are usually 10 - 12 feet long when they start producing pumpkins. If the plants look healthy it is just a waiting game. How big are your plants?

They are about three feet long right now.
I thought maybe I did something wrong. Last
fall I worked plenty of compost into the
soil and this Spring when I planted them I
used 12-12-12.
Jim

I remember the first year I grew pumpkins I was frustrated by this problem as well. I got tons and tons of male blooms, but it seemed like forever before I got a female bloom. I was sure something was wrong with my plants. But finally, after an eternity of anxious waiting, the first female bloom appeared. So hang in there! You should see one anyday!