One of the more unusual symptoms of pregnancy can be a strange metallic taste in the mouth. This is often described as having a mouthful of loose change, or sucking on a hand rail. It can also present as a sour, foul or rancid taste which permeates the taste of food and mouth, even when not eating or drinking.
Dysgeusia is the correct name for this distortion in a sense of taste, though some people refer to it as ‘metal mouth’. During pregnancy, dysgeusia is generally caused by pregnancy hormones, especially in the first trimester. However, some women experience changes in taste throughout their entire pregnancy.
Pregnant women can describe dysgeusia as an almost vague, unpleasant taste they may find difficult to explain. Dysgeusia can be mild or quite pronounced, causing changes in the way they view foods they usually love, and develop cravings for tastes they don’t usually enjoy.
Pregnancy is not the only cause for dysgeusia. Infection of the mouth, sinuses, upper respiratory tract or tooth infection can all contribute. Conditions of the gut, kidney or liver disease, diabetes and nutritional deficiencies are also associated with changes in taste.
Dysgeusia commonly occurs in the first trimester and usually goes away as the pregnancy progresses. It’s an unfortunate case of bad timing that dysgeusia occurs just at the time pregnancy nausea is more likely. Dealing with a queasy stomach is bad enough, but having a foul metallic taste in the mouth can really top it off.
For some pregnant women, successfully managing their nausea helps to improve the sensation in their mouth. For others, there seems to be no connection, and each is just as challenging, with or without the other symptom.
Dysgeusia is most commonly due to pregnancy hormones, especially oestrogen. This is one of the hormones which is particularly high during pregnancy. Oestrogen normally plays an important role in our perception of taste, food cravings and general enjoyment of food.
Because the level of oestrogen varies so much during pregnancy, the sense of taste can change too. This is why the taste of food when pregnant can vary so much. One week something tastes delicious and the next, well, it’s something else entirely.
Another cause for dysgeusia can be the connection between smell and taste. During pregnancy, it is common for women to develop a more acute sense of smell. The relationship between smell and taste is well known, but during pregnancy this can really ramp up. If something smells particularly strong, unpleasant or just “off”, then chances are the metallic taste in your mouth during pregnancy will increase as well.
Dysgeusia can also be caused by water retention. This occurs across all the body systems, including the cells in the mouth and taste buds.
Some people believe that dysgeusia is a safeguard against pregnant women eating foods which could potentially harm her or the baby. This mechanism of being repelled by certain foods may account for dysgeusia, but it can still occur even when food isn’t being eaten and when foods are perfectly safe. Perhaps it is one of those unexplained mysteries.
Another hypothesis is that dysgeusia serves as a protective mechanism to ensure a pregnant mother eats sufficient trace elements of calcium, sodium and iron.
Dysgeusia can be hard to control and even harder to stop completely. It does tend to settle as pregnancy progresses, with time you’re bound to feel it’s less pronounced. Generally there is a distinct improvement after the first trimester when hormones have settled and the body has adjusted to pregnancy.
Foods and sauces which increase saliva flow generally help. This increase helps to “wash away” the sensation. But for women who are already find they’re producing too much saliva and are already irritated by this, then increasing it further may not appeal.
Generally dysgeusia settles after the first trimester however, some women find they have it for their entire pregnancy.
During pregnancy, a general dental check-up is always recommended. There may be contributing tooth or gum issues adding to the metallic taste in your mouth. See your dentist for an assessment.
There is no proven link between dysgeusia and foetal harm. Though unpleasant, it’s not harmful to a pregnant mother or her baby.
Written and reviewed by Jane Barry, midwife and child health nurse on 12/01/20