If you're more than 20 weeks pregnant and get chickenpox, your doctor may prescribe an antiviral medicine called aciclovir. Although this doesn't cure the illness, it makes it less severe. You need to start taking this medicine within 24 hours of the rash appearing. Aciclovir is sometimes also prescribed for newborn babies. If you have been in contact with someone who has chickenpox and you haven't already had it yourself, contact your doctor as soon as possible. You can have an injection called varicella zoster immunoglobulin (VZIG), which contains antibodies against the virus. This will stop you getting chickenpox, but you need to have the injection within 10days of exposure to the virus.
Attribution: BUPA