Let me give you the statistic from the book
"Psychological development of children in orphanages."
It was published in Moscow by Pedagogika Press in 1990 in Russian.
What is remarkable about the book is that the data were collected
for many years, but the publication became possible only in the
free Russia. Information about what is known in this country as
FAS is scattered throughout the book (that is, there are no special
chapters devoted to this disorder). In the Introduction (pages
3 through 7) there are the following statistical data: 68% of
children placed in the system of "detskii dom" (orphanages)
were from parents who were legally deprived of their parental
rights due to a number of reasons, including "excessive drinking"
(the word "alcoholism" was not used, but I do not see
much difference at all). Further, the book says that 7% of children
were placed in orphanages due to their parents inability to care
for them because of illness. Here alcoholism is listed as one
of those "illnesses." It is up to you to make sense
of those figures. Bear in mind also that there is not a 100% correlation
between parental alcoholism and FAS in children (that is: not
all children of parents with alcoholism have FAS). The bottom
line, however, is that the probability of FAS in children from
Russian orphanages is relatively high.
I checked the incidence of FAS in the USA. One source indicated
that there are about 1200 children with FAS born each year in
the USA. Another two sources I checked complained about the considerable
difficulty in determining accurate FAS incident rates because
of a "lack of diagnostic agreement for the less severe variations
of the syndrome (what is sometimes called Fetal Alcohol Effect
- FAE), difficulties in recognizing the constellation of FAS facial
features, an inability to identify FAS central nervous system
dysfunction until several years after birth, etc. I assume that
if it is this difficult in the USA, it should be even more difficult