I always measure the pregnant girls to monitor the growth of their girth.  Dion measure 36 inches (92 cms) with 18 days to go.  37 inches usually means 8-10 pups.  I found an old post I'm going to share - some information on the female's gestation period which is 60-63 days.

Zero to One *Breeding takes place. *Within a few days, the sperm reaches the eggs and fertilization occurs.
Two *The fertilized eggs make their way to the uterus for implantation. *You may notice behavioral changes in your dog. She may become moody or more affectionate.
Three *Implantation has taken place and the embryos begin to develop. *Your dog may begin to display mood swings, appetite changes and breast tissue development.
Four *Fetuses can be felt in the uterine horns around day 28, and can also be seen by ultrasound. *The spinal cords are developing, and the fetuses are beginning to grow facial features. *Your bitch's uterus will shortly fill with fluids to protect the fetuses. After this, it will be weeks until the puppies can be felt again. *Your dog's appetite will likely increase, so offer her more of her food.
Five *The fetuses develop their sex organs and begin to look like actual puppies. The leg buds lengthen and develop toes. *Your dog's belly will begin to look noticeably swollen as the pups take up more space. *With less room for full meals, it's time to begin serving smaller meals more frequently.
Six *Pups continue to grow and pigmentation develops. The eyes now have lids and remain sealed until approximately ten days after birth. *Your dog is noticeably more uncomfortable at this point. She may vomit occasionally due to the extra pressure against her stomach. *You may also notice clear fluid discharge from her vulva. This is normal.
Seven *Puppies are well-developed, and now begin attaining size in preparation for birth. *You may be able to see/feel the puppies' movements in your bitch's abdomen. *Her breasts are well developed and probably contain a bit of colostrum or "first milk". *Your dog is noticeably tired and may begin searching for a place to whelp. Time to set up a whelping box.
Eight *The pups have fur and are now crowded in the uterus. You may notice a lot of activity as they get into position for the coming birth. *Your bitch may begin digging the bedding in the whelping box. This is natural "nesting" behavior. *Allow your bitch to feed freely as she is able.
Eight to Nine *The pups are ready for birth, and may be quite still as they rest in preparation for the marathon to come. *Your dog may appear uncomfortable and restless or anxious. *Time to begin taking rectal temperature readings 12 hours apart. Normal temperature is 100 to 101 F; a drop down near 97 F held for two consecutive readings indicates labor will begin within 24 hours.