Metallic Taste in Mouth Early Pregnancy: What Causes It?

Dysgeusia is the medical term for a change or distortion in the sense of taste. In early pregnancy, it most commonly presents as a persistent metallic, bitter or sour taste in the mouth that has no obvious cause. Many women describe it as similar to the taste of old coins, blood or having sucked on a piece of metal.

It is one of the lesser talked about early pregnancy symptoms but is actually experienced by a significant number of pregnant women, particularly in the first trimester. Some women find it comes and goes throughout the day while others notice it as a constant background taste that affects how food and drink taste.

Dysgeusia in pregnancy is closely linked to the heightened sense of smell and food aversions that many women experience in the first trimester. The three often occur together and are all thought to be driven by the same underlying hormonal changes.

The metallic taste of early pregnancy is primarily caused by the dramatic rise in oestrogen that occurs after conception and implantation. Oestrogen plays a significant role in regulating taste perception, and the sharp increase in levels that follows implantation can alter how the taste buds interpret flavours — often resulting in a persistent metallic or unusual taste.

HCG — the pregnancy hormone that begins rising after implantation — is also thought to contribute, which would explain why the metallic taste tends to be most prominent in the first trimester when HCG is rising most rapidly and tends to improve for many women as they enter the second trimester.

Increased blood volume and changes in saliva composition in early pregnancy may also play a role. The body produces significantly more saliva in early pregnancy — partly as a protective response to nausea and vomiting — and changes in saliva chemistry can affect how flavours are perceived.

A metallic taste can begin surprisingly early in pregnancy — some women report noticing it as early as 7-14 DPO, right in the middle of the two week wait, which is around the time of implantation and the initial rise in oestrogen and HCG.

For many women in the TTC community, a sudden unexplained metallic taste in the mouth is one of the first things that makes them think something might be different about that cycle — particularly because it is such an unusual symptom that does not have an obvious non-pregnancy explanation.

As with all early pregnancy symptoms, timing varies between women. Some notice the metallic taste very early before a missed period, while others do not experience it until several weeks into pregnancy. Both are completely normal.

The experience of dysgeusia in early pregnancy is described slightly differently by different women, but there are some common themes that come up repeatedly in the TTC and pregnancy community.

Most women describe it as a persistent taste of metal, coins or blood in the mouth that is present even when they are not eating or drinking. It can make food taste strange or unpleasant, and can make normally enjoyable foods suddenly unappealing.

• A persistent taste of metal, coins or blood in the mouth
• Food tasting different or strange — particularly sweet foods which may taste metallic
• Drinks tasting unusual — water in particular is frequently reported as tasting metallic
• The taste being present even on an empty stomach
• Food aversions triggered by the altered taste of certain foods
• The taste being worse in the morning or on an empty stomach
• A bitter or sour undertone alongside the metallic taste
• The taste coming and going throughout the day

A metallic taste before a positive pregnancy test is one of the more talked about early signs in the TTC community, largely because it is such a specific and unusual symptom. Unlike fatigue or breast tenderness which have obvious non-pregnancy explanations, a sudden metallic taste in the mouth without any other cause is harder to explain away.

Many women in TTC communities report noticing a metallic taste in the days before they got a positive test — sometimes as early as 8-10 DPO. If you are in your TWW and experiencing a persistent weird taste in your mouth that is new and unexplained, it is worth noting alongside any other symptoms you are having.

However, it is important to be aware that a metallic taste can also be caused by other things that have nothing to do with pregnancy. Certain medications, dental issues, vitamin and mineral deficiencies, and some infections can all cause taste changes. If you get a negative test and your symptoms persist, it is worth mentioning to a doctor.

Understanding when pregnancy-related taste changes can realistically begin helps to give context to any symptoms you are experiencing during the TWW. Here is a rough guide by DPO:

• 1-5 DPO: A metallic taste at this stage is not pregnancy related. Implantation has not yet occurred and pregnancy hormones are not present.
• 6-8 DPO: Implantation is occurring and oestrogen is beginning to rise. Very early taste changes could theoretically begin around this point in some women.
• 9-10 DPO: HCG is rising after implantation. Some women report the first hints of a metallic or unusual taste around this time alongside other early symptoms.
• 11-12 DPO: HCG and oestrogen are rising rapidly. A persistent metallic taste at this stage alongside other symptoms may be an early sign worth testing for.
• 13-14 DPO: Around the time of a missed period. A metallic taste that has developed or intensified as your period would normally be due leans more toward early pregnancy.
• After missed period: Persistent dysgeusia after a missed period is a well recognised first trimester symptom that tends to intensify as HCG rises.

Unlike some early pregnancy symptoms, a metallic taste in the mouth is not a typical PMS symptom. This makes it one of the more distinctive early pregnancy signs — if you are experiencing it in your TWW and it is new and unexplained, it is worth paying attention to.

Some women do notice mild taste changes premenstrually due to hormonal fluctuations, but a persistent and pronounced metallic taste is more specifically associated with early pregnancy than with PMS. If you have never noticed this symptom in previous non-pregnant cycles, its appearance in your TWW is more meaningful.

The key thing to consider is whether the taste is new and unexplained. If you have recently started a new medication, had dental work or are taking iron supplements, these are more likely explanations. If none of these apply and you are in the right window of your cycle, a pregnancy test is the sensible next step.

For women going through IVF, taste changes in the two week wait after a transfer can be particularly interesting to notice. Like heightened smell sensitivity, a metallic taste is not a commonly listed side effect of the progesterone supplementation used in IVF cycles — which means if you notice it after a transfer it may be a slightly more meaningful indicator than symptoms like fatigue or breast tenderness which are directly caused by the medication.

However, it is important not to read too much into any single symptom after an IVF transfer. The stress, the medication and the physical demands of an IVF cycle can produce a wide range of unexpected physical sensations that have nothing to do with whether the transfer was successful.

As always with IVF, the only reliable answer comes from a blood test or home pregnancy test at the appropriate time rather than from symptom interpretation alone.

Being aware of other possible causes of a metallic taste helps to give better context to what you are experiencing. There are several common reasons for dysgeusia that have nothing to do with pregnancy.

Iron supplements are one of the most common non-pregnancy causes of a metallic taste — if you are taking prenatal vitamins or iron supplements as part of your TTC routine, these could be the cause. Certain antibiotics and other medications also commonly cause taste changes as a side effect.

Dental issues including gum disease, tooth infections and recent dental work can all cause a metallic taste. Poor oral hygiene can also contribute. If you have any ongoing dental issues it is worth considering these as a possible explanation before attributing the taste to early pregnancy.

• Iron supplements and prenatal vitamins — very common cause
• Certain antibiotics and medications
• Dental issues — gum disease, tooth infections, recent dental work
• Vitamin and mineral deficiencies — particularly zinc deficiency
• Sinus infections and upper respiratory infections
• Acid reflux — stomach acid can cause a metallic or sour taste
• Kidney or liver conditions in some cases
• Neurological conditions affecting taste perception

A persistent metallic taste in the mouth can make eating and drinking unpleasant, which can compound the difficulty of managing nausea and food aversions in early pregnancy. There are some practical strategies that many women find helpful.

Good oral hygiene is one of the most effective ways to manage dysgeusia. Brushing teeth and tongue regularly, using an alcohol-free mouthwash and staying well hydrated all help to keep the mouth fresh and can temporarily reduce the metallic taste.

Some women find that certain foods and drinks help to counteract the metallic taste. Cold foods and drinks tend to have a less pronounced taste than hot ones, and tart or acidic flavours like lemon, lime and vinegar can temporarily override the metallic sensation. Plastic cutlery is also commonly recommended as metal cutlery can intensify the taste.

• Brush teeth and tongue regularly — particularly after meals
• Use an alcohol-free mouthwash to freshen the mouth
• Stay well hydrated — a dry mouth can intensify the metallic taste
• Try cold foods and drinks which tend to have less pronounced flavours
• Use tart or acidic flavours like lemon or lime to counteract the metallic taste
• Try plastic or wooden cutlery instead of metal
• Chew sugar-free gum or mints to mask the taste
• Rinse your mouth with a mild salt water solution

For most women, dysgeusia in pregnancy is at its worst in the first trimester and begins to improve as they enter the second trimester around 12-14 weeks. This improvement coincides with HCG levels stabilising and the body adjusting to the elevated hormone environment of early pregnancy.

Some women find the metallic taste resolves completely in the second trimester, while others notice it coming and going throughout pregnancy. As with all pregnancy symptoms there is significant individual variation and no universal timeline for when it will improve.

If dysgeusia is severely affecting your ability to eat and drink or is contributing to significant weight loss, it is worth mentioning to your midwife or doctor who may be able to offer additional support.

If you are experiencing a metallic taste alongside other possible early pregnancy symptoms and wondering whether to test, timing your test correctly is the most important thing you can do to get an accurate result.

The earliest most sensitive pregnancy tests can detect HCG is around 10-12 DPO, but for the most reliable result it is worth waiting until the day of your missed period and testing with your first morning urine. FMU is the most concentrated of the day and gives the best chance of detecting even low levels of HCG in very early pregnancy.

If you test and see a very faint line do not dismiss it. A line that appears within the reading window of the test — no matter how faint — is still a positive result. Retest in 48 hours and the line should be noticeably darker as HCG levels continue to rise.

A faint line on a pregnancy test in those very early days after implantation is incredibly common — HCG levels are still low and the line can be almost impossible to see even when you are genuinely pregnant. This is one of the most stressful parts of the TWW and something the TTC community discusses constantly.

Enhancing your test photo by adjusting brightness, contrast and using a red light filter can make even the faintest lines much easier to see. Saving your tests and comparing them side by side over several days is also hugely reassuring — a line that gets progressively darker confirms that HCG is rising as it should.

ClearLine is an iOS app that uses AI to analyse your pregnancy test photo and detect even the faintest lines. It includes image enhancement tools, a gallery to save and track all your tests over time, and a side by side comparison feature to help you watch the line progression — everything you need to make sense of those early uncertain results.