Pregnant women have a higher risk of severe disease than other women following infection with influenza. This factsheet provides guidance for health professionals on managing pregnant women presenting with suspected or confirmed influenza infections.
Influenza vaccination is recommended for all pregnant women regardless of gestation, and for women planning pregnancy.
Influenza vaccination during pregnancy should be routine: safety is well established for both mother and baby, and maternal antibody continues to protect the newborn in the critical first few months of life.
The timing of vaccination depends on the time of the year, vaccine availability, stage of pregnancy and the anticipated duration of immunity. Influenza vaccine can be given at the same time as pertussis vaccination (ideally at 28 weeks) but may be given earlier, and should not be delayed if the winter influenza season has begun or is imminent.
For more information, see the Maternal influenza vaccination - evidence review.
To avoid influenza, pregnant women should also be advised to take sensible precautions including:
There is no recommendation for well women to wear surgical masks, or to exclude themselves from regular activities.
Antiviral prophylaxis is not generally recommended for pregnant women, except in specific circumstances. For example, it may be considered in a pregnant woman who has had close contact with a patient with confirmed influenza, especially in the second or third trimester and in the presence of other co-morbidities.
For the purpose of this guidance, ILI is defined as a history of a fever (or temperature >38.0 C), and either a cough or sore throat. Pregnant women should be encouraged to present early if they develop an ILI, or if they develop any respiratory symptoms after close contact with a person who has an ILI. They should be assessed, diagnosed and managed on clinical grounds, noting that there are several differential diagnoses for people presenting with an ILI. Influenza typically involves other symptoms such as fatigue, headache, muscle aches and pains, and is more likely to be the cause of this constellation of symptoms during the influenza season.
The optimal laboratory test for influenza in an adult is a nasopharyngeal swab using virual or universal transport media. Viral respiratory screen should be requested – most NSW hospitals can provide a result within hours.
During influenza season treatment of pregnant women with ILI should not be delayed while awaiting test results. Treatment can be commenced on presentation with typical ILI symptoms, and suspended if laboratory testing is negative for influenza. Treatment with anti-influenza medicine (either oseltamivir [Tamiflu®] or zanamivir [Relenza®]) may be offered to pregnant woman at any stage of pregnancy. Although both drugs are classified as B1 (limited data indicating safety in pregnancy), use in pregnant women to date (mostly in second and third trimester) has not been associated with adverse fetal outcomes.
Experience of anti-influenza medication use in the first trimester of pregnancy remains very limited, so a careful discussion of the potential risks and benefits is essential before prescribing such agents. Experts have differing views as to the best drug to use in pregnancy: oseltamivir is a capsule, has a systemic effect but causes nausea and vomiting in some patients; zanamivir is inhaled, has a direct effect on the target organ (the lung) but can cause bronchospasm in some patients.
In the first trimester, the concern is largely about the effect the mother’s fever may have on the developing fetus, including miscarriage. Note that:
In the second and third trimesters, the concern is largely for severity of illness in the mother, as well as the potential effects of the mother’s fever on the developing fetus. Note that:
Around the time of birth, the concern is about both the severity of illness in the mother and the risk of transmission to the baby. Note that:
The spectrum of disease of influenza in newborns is unclear but serious infections occur.
Sensible efforts should be made to reduce the likelihood the baby will be infected from an infected mother, while minimising the effect on the mother-baby relationship. These include:
Breast feeding should be strongly encouraged. When breast feeding, bathing, caring for, cuddling, or otherwise being within 1 metre of the baby, the mother should:
These measures should apply to any carer or family member with influenza if it is essential that they interact with the baby.
Although these measures can be ceased when the mother is no longer infectious, continued good hygiene should be encouraged at all times.
Mothers requiring hospital care should not be prematurely discharged because they have influenza.
If discharged while still infectious, mothers should be provided with a sufficient supply of surgical masks to take home.
Prophylaxis is not recommended for the baby. Should the baby develop symptoms, the baby should be isolated from other babies, assessed urgently by a paediatrician, and if influenza is diagnosed, considered for treatment with anti-influenza medicine.
