Here's Why Dogs Love to Sniff Our Crotches When We're on Our Periods
I’m going to go ahead and put out a disclaimer — if you ever find yourself in the company of my dog, you’re very likely going to get a nose in the crotch. If you happen to be on your period, this is practically a certainty. I know, I know… it’s uncouth. I’m trying to teach my dog boundaries, but in the meantime, you should probably master your deflection skills.
Of course, the fact that this is even a conversation we have to have is curious, indeed. Why is it that dogs are more inclined to sniff our crotches when we’re on our periods? And — yes, while we’re going there — why in the hell do they raid the trash can and eat used tampons?
Dear dogs, ICYMI, this behavior is unbecoming. And, you know, disgusting.
Following some research that made me want to lose my lunch a little, I unearthed some actual scientific reasoning for this behavior, though. When it comes to dogs quite literally putting their nose where it doesn’t belong when a woman is on her period, it’s all about the pheromones.
So, we all know that dogs greet each other by sniffing butts, right? The reason behind this is that dogs’ dominant sense is smell. Reading scents is the way they glean information, and there is a certain sweat gland in particular that relays a lot of social information.
Called the apocrine glands, they produce the chemicals we know as pheromones. While most mammals (including dogs) have apocrine glands in various locations on their bodies, these glands are particularly concentrated in genital and anal regions.
Here’s a fun fact for you: Dogs have a unique scent-detection system called the vomeronasal organ that “reads” these info-loaded pheromones.
What does this have to do with a dog sniffing my crotch when I’m surfing the crimson wave, you ask? Well, humans have apocrine glands too — and ours are concentrated in the armpits and groin areas. Since most dogs can’t jump up and stick their sniffer in your armpit at any given moment, they rely on your crotch to do the talking.
Realizing that dogs seem to be sniff-happier around women who are ovulating, researchers ran an experiment with Australian shepherd dogs. The dogs were trained to sniff out cows that had just ovulated. Amazingly, the dogs were able to accurately determine which cows had just ovulated.
This suggests that women may produce more pheromones or experience a shift in pheromones during ovulation that makes their crotches more enticing to a dog.
Now, onto the more cringe-worthy offense of eating used tampons. While the same idea could still apply — that pheromones in menstrual blood are particularly appealing to pups — there could be another explanation: Dogs are just kind of gross sometimes.
Very technical, I know.
According to veterinarian Dr. Jeff Nichol, this kind of behavior is pretty par for the course with dogs… but should definitely be discouraged. “When [dogs] find a disgusting treasure in the trash, they assume it’s their birthday,” Dr. Nichol explains on his website. “The raunchier the better. Your job is to prevent access to anything with bodily discharges, including underwear.”
And, obviously, tampons too, which are dangerous because they can get stuck in the intestines and cause a life-threatening blockage that requires surgical removal.
The bottom line is dogs are omnivores and often opportunistic ones at that. If they happen upon a wastebasket with a fresh tampon full of pheromones wafting in their direction, they’re probably going to devour it.
Other possible reasons for your dog’s predilection for eating tampons (or anything they shouldn’t) include boredom and anxiety, so you may want to rule those out if the problem persists.
If you take your pooch to the vet, though, and he is given a clean bill of health, just remember your dog doesn’t know he or she is invading your personal space when they get “nosey” when you’re on your period. In fact, in a weird way, it’s kind of a compliment if they try to sneak a sniff.
While that may be one of the weirdest things I’ve ever written, I’m standing by it. Although, to be clear, I’ll still be swatting my dog away when my period rolls around. For, like, the next 12 years or so.
Originally published September 2016. Updated July 2017.