The advice published today (Wednesday, January 21) by the Royal College of Obstetricians and Gynaecologists (RCOG) also states that women should be asked whether they have previously had chickenpox or shingles when they book in for antenatal care, and that they should be advised to quickly inform a healthcare worker if they have potentially been exposed to the virus.
Professor Patricia Crowley, from University College Dublin, and co-author of the guidelines, said: "It is vital that pregnant women with symptoms of the virus should contact their GP as soon as possible and avoid contact with potentially susceptible individuals, such as other pregnant women and babies."
Dr Manish Gupta, co-chair of the RCOG guidelines committee, added: "Women may worry about passing the virus on to their baby.
"However, this is quite rare and depends on what stage of pregnancy the virus was transmitted."
Chickenpox in pregnancy can occassionally cause complications, but the NHS estimates this only occurs in three out of every 1,000 pregnancies.
If you've had chickenpox before, you should be immune to the virus, so there's no need to worry unless you develop a rash. But if you've never had chickenpox before and you come into contact with someone who has the virus, then you should speak to your GP or midwife immediately.
You should also contact your GP if you have been in contact with someone with chickenpox or shingles while you are breastfeeding or within seven days of giving birth.
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