Ring today, not in a few days

Tommy's states the position for pregnancy plainly: "Pregnancy puts you in the 'at risk' category from flu. That means you are more likely to get very ill with flu than other people are. It could also put your baby at risk if it is not treated quickly."

Its instruction follows from that: "Talk to your GP (doctor), midwife or maternity unit as soon as possible if you think you have flu, even if you've had your flu jab."

The reason for the speed is treatment timing. Tommy's explains that if you do have flu, your GP will prescribe medicine that might help reduce your risk of complications, "but it needs to be taken 48 hours after symptoms first appear", and that if that is not enough you may be admitted to hospital for specialist care. NICE's Clinical Knowledge Summary on treating influenza is the guidance clinicians work from, and it is built around the same principle of early antiviral use in at-risk groups.

The practical consequence: the phone call is worth making on day one, not on day four when you feel worse.

Call 999 if

Tommy's lists the signs of sepsis to act on immediately: fast breathing, slurred speech, seeming confused, clammy, blotchy or mottled skin that can look bluish on some skin tones, a rash that does not fade when you press a glass on it, not having a wee all day, or feeling very drowsy. Call 999 and say you suspect sepsis.

The NHS red-flag page for pregnancy also names breathlessness that comes on suddenly, breathlessness when lying down, or breathlessness with chest pain or dizziness as needing immediate checking. In the context of flu, new breathlessness is the symptom to escalate on rather than to wait out.

Telling flu from a cold

The NHS publishes a direct comparison, and it is more useful than any symptom list because it is about pattern rather than ingredients:

Flu appears quickly, within a few hours. A cold appears gradually over one to two days.
Flu affects more than just your nose and throat. A cold affects mainly your nose and throat.
Flu makes you feel exhausted and too unwell to carry on as normal. A cold makes you feel unwell, but you still feel well enough to do your normal activities.

The NHS list of flu symptoms is: a sudden high temperature, an aching body, feeling tired or exhausted, a dry cough, a sore throat, a headache, difficulty sleeping, loss of appetite, and less commonly diarrhoea, tummy pain, nausea and vomiting.

Tommy's adds the temperature threshold that applies in pregnancy: contact your GP, midwife or maternity unit if your temperature is above 37.5C, even with no other cold or flu symptoms.

What you can take

Tommy's is specific about both halves of this.

Paracetamol is safe in pregnancy and can bring your temperature down and ease the aches. Follow the packet, and ask your midwife or pharmacist if you are unsure.
Do not take ibuprofen or other NSAIDs while pregnant. Tommy's names them directly.
Do not take decongestants — also named by Tommy's, and exactly what most people reach for with a blocked nose and a temperature.

The NHS adds a warning that matters when people are feeling rough and buying several things at once: do not take paracetamol and flu remedies that contain paracetamol at the same time, because it is easy to exceed the recommended amount. A pharmacist can tell you which remedies are suitable.

Beyond that, the NHS self-care list is rest and sleep, and drinking plenty of water to avoid dehydration — it gives the useful marker that your pee should be light yellow or clear.

The vaccine, and why it comes up even when you already have symptoms

Tommy's says it is strongly recommended that all pregnant women and birthing people have the flu vaccine, whatever stage of pregnancy they are at. The NHS runs the flu jab in pregnancy as a routine part of antenatal care for the same reason the illness is treated urgently: pregnancy shifts the risk of severe illness.

Two things people get wrong here. First, having had the jab does not mean you cannot get flu, which is why Tommy's says to ring "even if you've had your flu jab". Second, being ill now does not mean the vaccine is irrelevant — it is worth asking about once you have recovered, and at any point in a subsequent pregnancy.

Why the caution is higher in pregnancy

Two things change. The immune system is modulated in pregnancy, and the lungs have less room to work with as the uterus grows, so respiratory illness has less margin. That is the mechanism behind the at-risk classification, and it is also why new or worsening breathlessness during a flu illness is the symptom that should prompt escalation rather than another day in bed.

What to expect when you ring

Expect to be asked when symptoms started — because of the antiviral timing — along with your temperature, whether you are breathless, how much you are managing to drink, and whether your baby's movements have changed. Your maternity unit will want to know about movements regardless of what else is going on.

You may be offered antivirals, advice on paracetamol and fluids, and a plan for what would make you ring again. Ask what that threshold is before you hang up, so the decision is already made if you deteriorate at 3am.

Flu When Pregnant