Now that you’re pregnant, do you find that your nose has taken over? If so, you’re not alone. A heightened sense of smell, which is sometimes called hyperosmia, is a common side effect of pregnancy.
Studies suggest that over two-thirds of women experience increased odor perception during gestation.1Cameron, E. L. (2014). Pregnancy and olfaction: a review.Cameron, E. L. (2014). Pregnancy and olfaction: a review. Frontiers in psychology, 5, 67.
Many women even report experiencing decreased olfactory thresholds well into the postpartum period.
The good news is that pregnancy is one of the leading causes of a heightened sense of smell. If you’re lucky, your new superpower might even kick in before you take that first pregnancy test.
We’re here to answer some of your most pressing questions about smell and pregnancy.
In this article:
What causes a heightened sense of smell during pregnancy?
A heightened sense of smell during pregnancy is quite common, leaving many to wonder what triggers this sudden sensory change. Ladies, like most pregnancy-related discomforts, researchers tend to blame this phenomenon on hormones.
Studies show that increased levels of reproductive hormones, including human chorionic gonadotropin, estrogen, and progesterone, may influence an expectant mother’s sudden detection or aversion to otherwise faint or easily ignored odors.2Doty, R. L., & Cameron, E. L. (2009). Sex differences and reproductive hormone influences on human odor perception.Physiology & behavior, 97(2), 213-228.
Researchers have also suggested that a heightened sense of smell during pregnancy may be an evolutionary mechanism.3Cameron, E. L. (2014). Pregnancy and olfaction: a review.Frontiers in psychology, 5, 67.
After all, a super snout keeps most women from inhaling toxins that could potentially harm their growing fetuses or help sense rotten food before it is eaten.
According to the National Geographic Smell Study, women already have a more acute sense of smell than men.4National Geographic Survey Tries to Make Sense of Smell
For many women, this powerful sense is even further amplified during pregnancy. Unfortunately, this unexpected and sudden change can cause several adverse side effects.
Some scientists have attempted to dig deeper into pregnant women’s olfactory functions. In a recent study, researchers from Umeå University in Sweden found that pregnant women’s superhuman senses of smell may be caused by cognitive changes.5Olofsson, J. K., Broman, D. A., Wulff, M., Martinkauppi, M., & Nordin, S. (2005). Olfactory and chemosomatosensory function in pregnant women assessed with event-related potentials.Physiology & behavior, 86(1-2), 252-257.
Pregnant women, when compared to non-pregnant women, did not have more sensitive odor discrimination and odor identification, but did have subjective differences especially as it related to extremely pleasant or unpleasant odors.
The discrepancy between “objective” and “subjective” olfactory function may relate to changes in the cognitive processing of chemosensory information during pregnancy.
Interestingly, after 36 weeks, women tended to have lower odor thresholds that persisted postpartum. Studies show that women with hyperemesis gravidarum, a severe form of morning sickness, are more likely to experience hyperosmia.6Hyperosmia
Strengthening this argument is the fact that women with congenital anosmia, or those born without a sense of smell, experienced fewer incidents of morning sickness.
What smells trigger this high sense?
Chemical smells, perfumes, cleaning products, scented candles, incense, and pungent foods are just a few things that may trigger a pregnant woman’s newfound sense of smell.
Of course, trigger odors and olfactory thresholds vary between one expectant mother and the next. Women experience a variety of reactions to their newfound smell sensitivities.
For example, some women experience mere discomfort, while others experience moderate to severe symptoms after prolonged exposure to strong odors.
A sense of smell may even be heightened to the point where a woman needs to avoid particular places and events.
According to one study, offensive odors account for over 50% of vomiting and nausea incidents during pregnancy.7Heinrichs, L. (2002). Linking olfaction with nausea and vomiting of pregnancy, recurrent abortion, hyperemesis gravidarum, and migraine headache.American journal of obstetrics and gynecology, 186(5), S215-S219.
Some women experience a heightened abhorrence toward odors they already despised. Meanwhile, others develop completely unfounded aversions.
While there’s no rhyme or reason to the smells that upset pregnant women’s noses, here’s a list of some of the more common triggers:
- Chemical scents (cleaning products, candles, incenses, paint, ink, etc.)
- Perfumes and colognes
- Food products (especially strong pungent ingredients, like herbs, onions, and garlic)
- Flowers and other natural odors
- Body odor, bad breath, and other human smells
Do pregnant women often experience a heightened sense of smell?
Studies show that most women experience an increased sense of smell during their first trimesters and first pregnancies.8Doty, R. L., & Cameron, E. L. (2009). Sex differences and reproductive hormone influences on human odor perception.Physiology & behavior, 97(2), 213-228.
During these times, many women find that odors that were once normal now become intolerable. A woman’s olfactory hypersensitivity may even trigger headaches, nausea, vomiting, and morning sickness.
hCG usually starts occuring a few days after implantation and usually peaks between the eighth and tenth weeks of pregnancy.9Kumar, P., & Magon, N. (2012).Hormones in pregnancy. Nigerian medical journal: journal of the Nigeria Medical Association, 53(4), 926-934.
Many researchers think this is why most pregnant women regain their normal sense of smell during the third trimester of pregnancy.
The good news is that your heightened sensitivity is likely to vanish later in pregnancy. What’s more, the majority of women do not continue to experience a heightened sensitivity to odors after giving birth.
Side effects of a heightened sense of smell
An increased sense of smell is directly linked to first-trimester nausea, vomiting, and morning sickness. However, strong odors can also trigger migraine headaches.10Dixit, A., Bhardwaj, M., & Sharma, B. (2012). Headache in pregnancy: a nuisance or a new sense?.Obstetrics and gynecology international, 2012.
Many pregnant women experience odd cravings and even stranger aversions during pregnancy. A sudden revulsion to the smell of particular food products can prompt some pregnant women into making poor dietary choices.
You may be able to avert this crippling sense of smell by avoiding the most pungent of foods. Do your best to maintain healthy prenatal eating habits.
Ways to cope with a heightened sense of smell during pregnancy
Looking for a way to tone down your enhanced whiff-ability? While your nose may not have an on/off switch, there are a few things you can do to decrease the impact of your olfactory senses, including:
- Surround yourself with pleasant smells: When all else fails, surround yourself with smells that please that hard-working nose of yours. Lavender, ginger, and peppermint are just a few scents that are known to reduce morning sickness. You may have to experiment to find scents that soothe your newfound nose!
- Turn off the oven: Hot foods tend to be extra aromatic. Opt for foods with odors you can tolerate. Or else, stick to uncooked delicacies.
- Increase air flow: Open your windows, breathe deeply, and get outside. Fresh air is often the best antidote for strong odors. You could also eliminate some indoor smells with the help of an air purifier.
- Chew gum: Some women say that chewing peppermint gum helps reduce the effects of a heightened sense of smell.
- Try a saline spray: If you’re caught in the peripherals of an upsetting odor, consider spritzing both nostrils with saline spray.
- Toss the scented products: If you notice that synthetic smells are making you nauseous, it may be because you have a chemical intolerance that’s being exasperated by pregnancy. Switch these products for unscented or all-natural alternatives.
- Quell your morning sickness: Morning sickness symptoms are often triggered, or worsened, by unpleasant odors. Eat small, frequent, bland meals, and snack often to avoid developing an empty stomach. According to Michigan Medicine, vitamin B6 is also known to improve pregnancy-related nausea.11Vitamin B6 for Morning Sickness
- Wash clothing frequently: Studies show that odors cling to synthetic fibers, such as polyester.12Polyester clothes stink after exercise; cotton, not so much
sciencedaily.com/releases/2014/09/140903163635.htm Opt for cotton fabrics, (undeniably more comfortable) and wash your clothes frequently to eliminate lingering smells.
- Mask it: Carry essential oil, flavored lip balm, lotion, tissues, or handkerchiefs with you wherever you go. When you can’t escape a foul smell, mask it with a scent you can tolerate. Otherwise, cover your nostrils, breath deeply through your mouth, and keep on cruising.
- Ask and you shall receive: Is your coworker’s cologne making you nauseous? Does the lingering scent of your partner’s smoking habit send shivers down your spine? Kick up a conversation about your superhuman sniffer. You’d be surprised at how understanding people can be.
Frequently asked questions
Is my heightened sense of smell interfering with my ability to do my job?
If a heightened sense of smell or morning sickness is impacting your ability to work, it may be time for you to have a conversation with your manager.
It may be necessary for you to switch assignments with another employee or cease the use of strongly scented chemicals in the office.
When will I get my regular sense of smell back?
Many pregnant women report that their sharpened sense of smell disappeared after the first trimester, while others say that their elevated odor detection continued well into their third trimester.
Will my sense of smell change or just increase?
A heightened sense of smell is often accompanied by new smell preferences. As with pregnancy food cravings, many women experience sudden distaste or obsession with seemingly random odors.
Could my hyperosmia be triggering my anxiety?
Unfortunately, yes! Some pregnant women develop osmophobia or the fear of bad smells. Exposure to strong odors can trigger stress and anxiety in expectant mothers.
If experiencing odor-related anxiety, talk with your doctor, loved ones, and coworkers. It really helps to develop a strong support network as you grow the baby inside you. Studies show that anxiety can harm your pregnancy.13Shahhosseini, Z., Pourasghar, M., Khalilian, A., & Salehi, F. (2015). A review of the effects of anxiety during pregnancy on children’s health. Materia socio-medica, 27(3), 200.
My bionic nostrils aren’t working, should I be worried?
Pregnancy affects each woman differently. Your failure to pick up your husband’s scent trail doesn’t mean there’s something wrong with you or your growing baby.
You’re just one of those fortunate pregnant women who don’t experience stomach-churning side effects every time they catch wind of a foul odor.
An elevated sense of smell is just one of many odd, yet totally common, side effects of pregnancy. The good news is that your newfound supersense will likely cease by your third trimester.
At the very least, it should be gone by the time your bundle of joy arrives. In the meantime, do your best to reduce exposure to foul odors.
Keep some scented distractions on hand to avoid developing osmophobia and other uncomfortable symptoms.