Nofia,
I found something in the July 12, 1996 MMWR from the Centers for Disease
Control that may help you more than my previous message.

"...Congenital varicella syndrome, first recognized in 1947, can occur
among infants born to mothers infected in during the first half of
pregnancy and may be manifested in low birthweight, cutaneous scarring,
limb hypoplasia, microcephaly, cortical atrophy, chorioretinitis,
cataracts, and other anomalies.  Aggregate results from prospective
studies indicate that congenital varicella syndrome developed in four
(0.7%) of 564 infants born to mothers who had varicella in the first
trimester of pregnancy.  In a prospective study in the United Kingdom
and West Germany from 1980 to 1993, a higher risk for congenital
varicella syndrome was observed when maternal infection occurred during
13-20 weeks' gestation than when infection occurred from conception to
12 weeks' gestation (2% versus 0.4%, respectively)."

Kimberly Elms
Arizona State University
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