How Does a Dog Act When Pregnant?

You'll notice physical changes after the first trimester.
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A dog’s pregnancy consists of three trimesters covering an average of 63 days. You may not even know your dog is expecting until noticeable physical and behavioral changes start to take place, usually around the 21-day mark. According to Michigan State University, that’s the approximate time you’ll start to see a discernible weight gain and some other behaviors that indicate your dog is pregnant.

First Trimester

Your dog may experience morning sickness for a few days in her first trimester. If this happens, several small meals served daily can help. You may notice a slight weight gain, and if you suspect your dog is pregnant, a vet can palpate her uterus at this time to feel for fetuses. Anticipate a slight decrease in energy levels and appetite at this stage and follow your vet’s recommendations for appropriate dietary changes.

Second Trimester

By the second trimester, your dog’s nipples will begin to enlarge and darken and you’ll notice weight gain around her middle. Her abdomen will be firm to the touch. She may act tired or lazy, as the extra weight may make it difficult for her to participate in her normal activities. Appetite generally increases as caloric need increases to nourish developing puppies. According to Vet Street, moderate levels of exercise are appropriate at this stage.

Third Trimester

Your dog will begin nesting behaviors during her third trimester and seek out a safe, warm place to give birth. Provide your dog with a sheltered, quiet area of your house and line it with towels or soft blankets. Your dog’s energy levels will decrease as she nears birth and she may “wiggle” when she walks as her belly and mammary glands will be swollen. She may also be irritable and lethargic, which are normal behaviors during this stage of pregnancy.


Your dog may become restless as she nears the final days and hours of her pregnancy. She may shred bedding to make a nest for her babies and seek solitude or hide if you haven’t prepared an appropriate birthing place. You may also find her shivering, pawing at the ground or even vomiting right before labor begins. Reassure her in a calm tone, provide water and be on hand to assist with whelping to ensure your dog doesn’t become stressed during the process.