Why can I squeeze fluid from my dog’s nipples?

Fluid from a dog's nipples is common late in pregnancy — after about day 50, hormones make the mammary glands secrete a little milk, and a small amount of whitish fluid can be expressed before labor; this is normal. If the abdomen looks large, prepare for whelping. If the dog isn't pregnant, it may be a false pregnancy; get a vet ultrasound to confirm, and consider spaying a female with frequent false pregnancies.