There are some excellent statistics on this subject in the study,
"Counting Flocks and Lost Sheep: Trends in Religious Preference Since
World War II"
By Tom W. Smith, Univerity of Chicago, hosted by umich.edu:
Survey respondents were specifically asked if they were raised in
particular religion and whether they had ever switched to another
denomination or preferred no religion at all. Overall, 35.7% of those
who were raised with a particular religion had at some point switched
to another religion or no religion. Stated another way, about 2/3rds
stay with the religion in which they were raised.
Table 29 of the study presents the percent of people raised in a
particular religion who reported currently being members of that same
A. Major Religions
B. Major Protestant Denominations
Southern Baptist 71.8
United Methodist 63.0
Disciples of Christ 63.9
"Counting Flocks and Lost Sheep:"
Another study indicates that divorce (either of the person's parents
and of the person himself/herselfr) is a major factor in whether a
person continues the religion of his or her parents.
"Among Americans raised as conservative Protestants, experiencing
parental divorce as a child increases the likelihood of switching to a
moderate Protestant denomination by almost one-half (Odds Ratio of
1.478) and of repudiating religion altogether by over two-and-a-half
times (Odds Ratio of 2.629). In the especially high likelihood that
parental divorce in childhood will cause a conservative Protestant to
apostatize from religion entirely, the authors of the new study
discern "a rejection of both family and religious community."
Indeed, the researchers see "strong and consistent effects of
having experienced parental divorce in childhood on the likelihood of
religious disaffiliation (apostasy) for all groups." And although
their primary focus is parental divorce, the researchers also
determine that adult children's own divorces affect religious identity
in a curious way, making these adults "less likely to switch"
religious denominations, but more likely to repudiate religion
altogether, so "leading to an increased likelihood of switching from
Catholic to None, moderate Protestant to None, and conservative
Protestant to None."...
(Source: Leora E. Lawton and Regina Bures, "Parental Divorce and the
'Switching' of Religious Identity," Journal for the Scientific Study
of Religion 40.1 (2001): 99-111, emphasis added.)"
I also used the new "search inside" feature at Amazon.com to find some
books with additional statistics that you might find interesting:
"Naturally, our explorations have taken us away from where we started,
and up to 20 percent of Americans say they no longer practice the
religion of their parents."
source: page 92
"Sixty Trends in Sixty Minutes," hosted by Amazon.com
"Of the generation born after World War II, 95 percent received a
religious upbringing, yet some two thirds of the seventy-five million
American baby boomers left the religion of their parents by their
early adult years, according to Dr Wade Clark Roof, author of
Spiritual Marketplace: Baby Boomers and the Remaking of American
Religion. While many returned to the fold later, millions of baby
boomers and younger adults are experimenting with Eastern religions
and independent spiritual practices."
source: Page 90
"What Kids Really Want that Money Can't Buy," hosted by Amazon.com
"A 1993 survey I conducted with one hundred middle-class Caucasian
grandmothers found that...
16 percent said that their children had chosen a different religion
but allowed the grandparents to teach their own religion to the
grandchildren. Only 4 percent said their children are of different
faiths and do not want them to talk about religion with the
source: Page 47
"The Grandparent Guide : The Definitive Guide to Coping with the
Challenges of Modern Grandparenting," hosted by Amazon.com
"Survey studies show that the great majority of Americans raised in
particular denomination remain members after they become adults. But
of persons who report that the religious affiliation of their parents
was "none," less than 40 percent remained without a religious
affiliation when they grew up. Thus, the majority of offspring of
"nones" convert to some religion (Kluegel, 1980)."
source: page 47-48
"The Future of Religion: Secularization, Revival, and Cult Formation,"
hosted by Amazon.com
"Keep in mind also that about 30 percent of Americans switch religions
at some point in their adult lives and a third of those switch more
than once (Roof, 1989)."
source: page 69
"Sociology of Families," hosted by Amazon.com
"parents religion," leave, switch, etc
I hope this helps.