I found this for you, I guess you need to treat chicken pox in the way many pregnant women deal with Rubella stay away of contagious people and seek medical help if you have reasons to believe you may have been exposed to the disease.
I found the following, which may help:
What if I develop chickenpox when I am pregnant?
Most pregnant women who have chickenpox recover fully and their baby is fine. However, as discussed above, the illness tends to be unpleasant and there is some risk of complications. See separate leaflet called 'Chickenpox in Adults' which gives details of the infection itself. In short:
See a doctor urgently if you suspect that you have chickenpox when you are pregnant, or within seven days of giving birth.
If you do develop chickenpox, you (and your baby if newborn) should be reviewed daily. You may need a hospital assessment if you have lung disease, are a smoker, or are taking treatment which affects your immune system (such as steroids). See a doctor immediately if you have: a severe rash, a bleeding rash, chest/breathing problems, drowsiness, vomiting, or bleeding. You may need treatment in hospital.
Antiviral medication is an option to treat chickenpox, but it must be started within 24 hours of the rash appearing to be of benefit. It does not cure the illness, but tends to make it less severe. It may help to prevent complications developing in mother and baby (described above).
You are likely to be referred for a detailed ultrasound scan at 16-20 weeks of the pregnancy, or five weeks after the infection has cleared if the infection was later on in the pregnancy. The aim of this is to look for signs of fetal varicella syndrome.
If you develop chickenpox within seven days before or after the birth of your baby, the baby can be given immunoglobulin treatment (described above). This aims to prevent chickenpox developing in the baby.
Avoid other pregnant women and newborn babies until all the spots have crusted over (commonly about 5-6 days after onset of the rash).