The internet is full of anecdotal accounts of someone’s pet cat or dog acting funny around its newly pregnant owner. There are stories of cats who were once aloof and solitary suddenly rubbing against your legs and purring. Or sweet, affectionate dogs who now growl when you walk into the room. Or dogs who bark when anyone comes near you—even your husband.
There doesn’t seem to be a single uniform way that animals respond to pregnant women, but most pet owners know their animals well enough to sense that something is different. It’s not surprising that an animal would act differently around a visibly pregnant woman whose whole daily routine has changed. Dogs might get impatient when their pregnant owners walk more slowly, and cats could get annoyed that only the husband now scoops the cat litter. Animals may not understand what’s going on, but they can definitely sense that something big is happening.
But what about before you’ve even taken a pregnancy test? Do pets have a sixth sense that enables them to detect pregnancy before humans do?
The answer, according to animal behavior specialists, is yes: pets probably can sense pregnancy. But it’s not due to a sixth sense—it’s their excellent sense of smell.
During pregnancy, a woman experiences profound hormonal changes, producing much more estrogen, progesterone, and chorionic gonadotropin than normal. Cats and dogs have very refined senses of smell, and may pick up on these changes—even before a pregnancy test does.
Pregnancy isn’t the only human condition where animals have been known to sense changes before humans do. Dogs have been used to detect cancer in human breath.
No one really knows for sure the impact that early pregnancy hormones has on animals, but if your pet is acting weird, go ahead and count it as a vote in favor of testing.