How To Calculate Your Dog's Due Date

If you purposely bred your dog or know when she may have been bred, you can calculate the dog due date based on the average gestation period of dogs, which is 63 days. If you don't know when she was bred, you will have to rely on testing done by your veterinarian and her signs and symptoms to determine when the puppies are due.

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While 63 days, or approximately nine weeks, is the average gestation period, dog due date accuracy is not 100 percent. Some dogs may give birth as soon as 58 days after breeding or as long as 70 days after breeding. If you know the date your dog was bred, you can count out 63 days to determine the due date or use an online dog gestation period calculator.

If you aren't sure when your dog was mated, you can watch for signs that may indicate where she is in her pregnancy. Your dog will not show any outward signs of pregnancy until week three, when the fetuses implant on the placenta. Morning sickness may begin at this point and continue through week four. The fourth week is also when your dog will start to noticeably put on weight and develop enlarged nipples.

After the fourth week of pregnancy, around day 28 to 30, your veterinarian will be able to examine the puppies and detect heartbeats with an ultrasound. Your veterinarian can help estimate your dog's due date based on what he sees on the ultrasound.

There are several ways to confirm that your dog is pregnant. A dog pregnancy test is effective once your dog is at least 30 days pregnant. It looks for the hormone relaxin to confirm the pregnancy. Palpating your dog's abdomen is effective when your dog is 21 to 35 days pregnant. During this phase, you can feel each fetus in her belly. Once she progresses beyond this point, she may just feel fat, and you may not be able to feel the fetuses in her abdomen.

X-rays can also be used, but they are not effective until the fetuses develop their skeletal structure. The spines of the puppies are not visible until around day 42 through 45. Ultrasound is typically the best way to confirm pregnancy and evaluate the health of the puppies. Ultrasound is best done when your dog is 25 to 35 days pregnant.

A dog's pregnancy lasts for nine weeks. During the first trimester, which is three weeks, cells in fertilized eggs begin to duplicate and implantation begins. During the second trimester, you will see visible changes in your dog as her belly grows. The fetuses continue to grow, and internal organs develop.

During the final trimester, the puppies continue to grow and develop. Your dog's belly will continue to increase in size, and you will likely notice she is not as active. The hair on her abdomen will shed out, exposing her nipples.

As your dog approaches her due date, watch for signs that she is ready to go into labor. She may lose her appetite, and her waist may appear to narrow as the puppies begin shifting. She will likely become restless and start pacing and digging.

The most accurate way to determine when she will go into labor is to monitor her body temperature. Your dog's normal temperature is between 100.5 and 102.5 degrees Fahrenheit, but about 24 hours before she goes into labor, her body temperature will drop to 99 degrees or less.