Can I eat ham while pregnant?

The verdict

Ham is two different foods wearing one word, and they get different answers.

Cooked ham, the pink sliced kind in a sandwich, is treated in the UK as a food to be careful with rather than a food to avoid. The NHS lists any processed, cold pre-cooked meats, such as ham or chicken, in that category, with the instruction to keep chilled and eat before the use-by date.

Elsewhere it is stricter. The FDA and ACOG both say to avoid hot dogs, deli meats and luncheon meats unless they are reheated until steaming hot just before serving. FSANZ puts cold ready-to-eat meats, both unpackaged from deli counters and sandwich bars and packaged sliced meats, in its higher-risk table, with freshly cooked or thoroughly reheated to steaming hot as the safer alternative. Ireland's HSE names ready-to-eat sliced meat, such as sliced ham, and advises avoiding deli counters because food hygiene may be compromised.

Dry-cured ham, meaning parma ham, prosciutto, serrano and similar, is not cooked at all. It is restricted everywhere. The NHS says cold cured meats such as salami, pepperoni, chorizo and prosciutto should be cooked until steaming hot before eating, and the HSE names parma ham directly.

Why cooked ham is restricted at all

It was cooked. The problem is what happens afterwards.

Listeria grows at refrigerator temperature, which very few food poisoning bacteria do. That means a cooked meat which is sliced, packed and then held chilled for days or weeks gives any contamination introduced after cooking a long, cold opportunity to multiply. The FSA lists cold pre-cooked meats and deli meats among the ready-to-eat foods in which listeria is more commonly found.

The FDA's own listeria page names deli meats among the foods through which you can get listeriosis, and notes that pregnant women are about ten times more likely to get listeriosis than other healthy adults, because immune systems are altered during pregnancy.

The consequences are why the advice exists. Listeriosis in pregnancy can cause miscarriage, stillbirth, premature delivery or serious infection in a newborn. The illness itself is often mild or unnoticed in the mother, which is exactly what makes it difficult.

The deli counter versus the sealed pack

Two of the four authorities here distinguish between them, and it is worth knowing why.

FSANZ's higher-risk row names unpackaged meats from delicatessen counters and sandwich bars as well as packaged sliced meats, but its cheese precaution elsewhere is to buy products packaged by the manufacturer, and the HSE explicitly advises avoiding deli counters as the food hygiene may be compromised.

A sealed pack has a documented use-by date, was sliced in a controlled environment and has been handled once. A deli counter slices to order using a machine that also handles other products, with staff moving between items. If you are going to eat cold ham in the UK where it is permitted, the sealed pack is the better version.

What steaming hot means for ham

The instruction outside the UK is to reheat until steaming hot, which is a real threshold rather than a figure of speech.

FSANZ specifies reheating food thoroughly until it is steaming hot at 75C. The FSA's cooking guidance says the middle of the food should reach 70C for two minutes, or an equivalent such as 75C for 30 seconds, and that visual cues include steam rising from the surface and from the middle when it is cut into.

In practice: ham in a toasted sandwich that comes out hot right through, ham baked into a quiche or a pie, ham in a hot pasta bake, and ham on a pizza from the oven all clear it. Ham warmed briefly in a panini press that leaves the middle cool does not. Ham in a cold sandwich does not.

A microwave works, though it heats unevenly. FDA advice for microwaving is to cover, stir and rotate food to cook it evenly and to allow standing time before checking the temperature.

Gammon, Christmas ham and ham hock

Gammon is cured pork sold raw, and it is cooked before eating like any other pork joint. Cooked through, it is safe. The NHS lists thoroughly cooked pork as safe, and the FSA notes pork can carry bacteria all the way through so must be cooked right through.

A glazed Christmas or holiday ham that has just come out of the oven is hot cooked pork and is safe. The same ham three days later, cold from the fridge, is a cold cooked meat and falls under the advice above. Reheat the slices until steaming hot, or use them in a hot dish.

Ham hock, pulled ham and ham in a soup are all cooked hot dishes. Terrines and potted hams are chilled ready-to-eat products and are closer to pate, which the NHS lists among foods to be careful with and the FDA lists among refrigerated meat spreads to avoid.

Cured hams and toxoplasmosis

Parma ham, prosciutto crudo, serrano, jamon iberico, coppa and speck are cured, not cooked. They carry the same two concerns as salami: the NHS notes a small risk of toxoplasmosis from raw, undercooked or cured meat, which can cause miscarriage, and the listeria risk that applies to all cold ready-to-eat meats.

Cooking is the fix. Prosciutto crisped in the oven, wrapped around something that is then roasted, or fried until it shatters has been cooked. Prosciutto draped over a melon or laid on a finished pizza has not, and warming it on top of a hot pizza is not the same as cooking it.

Freezing is sometimes suggested as an alternative for toxoplasma. It is not part of current NHS advice for pregnancy, and it does nothing about listeria, which survives freezing. Cook it instead.

If you have already eaten some

A cold ham sandwich is a low risk. Listeriosis is rare in absolute terms, and the NHS's position on foods that should have been avoided is that a small amount, if you did not become ill, is unlikely to affect your baby.

Because listeria has a long and variable incubation, keep an eye out rather than dismissing it. ACOG notes symptoms may appear as late as two months after eating contaminated food, and lists fever, chills, muscle aches and diarrhoea or upset stomach, with stiff neck, headache, confusion or loss of balance in more serious illness. ACOG's advice if you think you ate something that puts you at risk is to talk with your obstetrician, who can monitor symptoms and decide whether testing is needed.

Contact your midwife or GP the same day if symptoms appear, and say what you ate and when. Listeriosis is treated with antibiotics.

Where guidance genuinely differs

This is one of the sharpest divides in pregnancy food advice, and it is not about the food but about how much residual risk each country accepts in a very common product.

The UK permits cold cooked ham with a chilling and use-by instruction, on the basis that the risk from a properly stored product within date is low. The US, Australia, New Zealand and Ireland ask you to heat it, on the basis that listeria in deli meat has caused enough real harm to justify the inconvenience.

Neither is unreasonable. If you want a single rule that satisfies all of them, heat the ham. If you are in the UK and would rather not, buy sealed rather than sliced at a counter, keep it cold, and eat it within its date.