Risk of the damage of fetus by maternal rubella is maximum if mother gets infected in
Congenital Rubella Syndrome (CRS):

CRS is said to have occurred if:

– Infant has IgM rubella antibodies shortly after birth, or
– IgG antibodies persist for more than 6 months

Major determinant of extent of fetal infection in CRS: Gestational age at which fetal transmission occurs,

– Infection in I trimester: MOST DISASTROUS TIME
1. Abortions
2. Still births
3. Skin lesions: blueberry muffin lesions
4. ‘Triad of Congenital Rubella Syndrome’
i. Sensorineural deafness
ii. Congenital heart defects (MC is PDA)
iii. Cataracts
– Infection in early part of II Trimester: Deafness (only)
– Infection after 16 weeks POG: No major abnormalities
Risk of fetal damage in CRS:
20-24 weeks of pregnancy
24-28 weeks of pregnancy
32-36 weeks of pregnancy
6-12 weeks of pregnancy