Redditors Claim They Can Smell When Someone Is Pregnant. Is That Really A Thing?

Over on Reddit, people are discussing whether it is possible to "smell" that somebody else is pregnant, with several users claiming anecdotal evidence that you can smell when somebody has a fetus forming inside them. 

"This might sound really weird, but I’m being completely serious and would really like some insight… For some reason, I seem to be extremely sensitive to two very specific scents that I pick up from people - even from a few meters away," Reddit user scoundrelbird wrote last week, claiming that they can smell the scent of death on people close to the end, as well as the smell of pregnant women and very young babies.

"The first one fills me with dread and anxiety (obv), it’s AWFUL. The second one, oddly enough, makes me nauseous to the point of gagging or having to walk away," they added. "For example, I’ve unintentionally ruined surprise pregnancy announcements from friends because I started feeling sick around them long before they shared the news."

Others in the comment section supplied their own anecdotes, claiming that they can smell pregnancy as well, or have had their pregnancy sniffed out by others.

"I was 6 weeks pregnant, hadn’t told anyone at work and obviously wasn’t showing. My student comes up to me and whispers, 'I just know you are pregnant, I can smell you. You smell like my aunties and I can see it in your eyes'. Say what now! Lol. She was so excited for me all year and never shared her thoughts until I told my class," user 0caloriecheesecake wrote.

"I taught Kindergarten Self Contained Autism and three of my students kept rubbing my stomach before I knew I was pregnant," bootyprincess666 added. "It started randomly and I just figured 'aww they like me', but no they knew before I knew LOL."

So, is this actually a thing? Well, as you may have imagined, given we have highly accurate pregnancy tests (gone are the days when we would inject pee into a frog), not a lot of research has been put into this phenomenon. But there is a little, and though it is a small study, it does indicate that there might be a little truth to the idea.

"Female chemical signals underlie the advertising of sexual receptivity and fertility," a paper on the topic explains. "Whether the body odor of a pregnant woman also has a signaling function with respect to male behavior is yet to be conclusively established. This study examines how the body odors of ovulating and pregnant women differentially affect the behavior of heterosexual men."

For the double-blind study, the team collected body odor samples from five pregnant women, and five matched controls whose samples were collected during ovulation, as well as a control with no odor present. Eighteen heterosexual men were then exposed to these odor samples while viewing portraits of female faces, and asked to rate their attractiveness, as well as whether they believed the person to be pregnant. The team also looked at the brain activity of the male participants, looking at which regions were activated during the experiment.

This might sound like an unusual idea, but previous research had indicated that "the body odor of (near-)ovulating women is rated as more pleasant and sexually arousing by heterosexual men compared to that of the same women in their luteal phase of the menstrual cycle," warranting further investigation. 

Sure enough, the team found that the male participants rated the faces as more attractive when presented with the odor collected during ovulation. As well as this, they found that they were less likely to rate the face as belonging to a pregnant person when exposed to the same odor. The team also found that different areas of the brain were activated when exposed to the different odors. 

"While neither OV [ovulating condition] nor PRG [pregnant condition] altered the perceived attractiveness of a presented face, the men tended to identify the women as pregnant while exposed to a PRG body odor," the team explains. "On the neural level, OV activated a network of the frontotemporal and limbic regions, while PRG activated the superior medial frontal gyrus."

While only a small study, the authors believe that it could indicate that smell could have an effect on male behavior around women.

"The results suggest that the detection of sexual availability activates the male brain regions associated with face processing and reward/motivation, whereas sensing pregnancy activates a region responsible for empathy and prosocial behavior," they write. "Thus, the female body odor during pregnancy likely helps foster circumstances conducive to the future care of offspring while the body odor advertising sexual availability promotes mating behavior. The brains of heterosexual men may be capable of unconsciously discriminating between these two types of olfactory stimuli."

In short, though it might be a bit of a stretch to believe that some people are particularly able to sniff out a pregnancy, there might be some truth to the idea that people can unconsciously pick up on subtler signs of pregnancy, if you are close enough to smell it. But pregnancy tests remain far more reliable than sniffing.

All “explainer” articles are confirmed by fact checkers to be correct at time of publishing. Text, images, and links may be edited, removed, or added to at a later date to keep information current.