Syrian hamsters reach sexual maturity within weeks of their birth, after which females go into heat every four days. The gestation period for a Syrian hamster is only about 15 to 17 days. As such, only a keenly observant owner will be able to recognise the signs of pregnancy, which closely mimic those seen in the human world. Pregnant Syrian hamsters should be allowed to follow their instincts, which may mean less handling by their owner and more frequent feedings.
Pregnant Syrian hamsters experience an increase in appetite and weight gain around the abdomen, which becomes most noticeable about 10 days after mating has taken place, according to the Ask the Vet website. Unlike with humans, a pregnant hamster's abdomen grows mostly in girth, resulting in a barrel-like appearance around the midsection. In addition, a pregnant Syrian hamster's nipples will become more pronounced.
Mothers-to-be among all species typically begin a nesting process, and Syrian hamsters are no exception. As the hamster advances in her pregnancy, she will become more active in preparing the nest in which she will deliver and care for her babies. She does this by gathering additional cage bedding material in one area of the cage and also storing extra food in that same section.
Hormonal changes that take place during pregnancy may make the hamster more nervous and jumpy than usual. As a result, a normally loving Syrian hamster may become prone to biting her owner. She may shy away from the handling that she normally loves and become aggressive to any other hamsters with which she comes into contact. Just hours before giving birth, the pregnant hamster's rate of breathing will double and she will grow increasingly restless.