Conversation so far:
who is julia?
16-year-old groupie Julia Holcomb.
what was her relationship to tyler?
They dated.
when did they date?
three years.
did Tyler discuss their relationship?
Holcomb was referred to as "Diana Hall" by the editor of the Aerosmith autobiography Walk This Way in an attempt to conceal her identity.
why were they concealing her identity?
CANNOTANSWER.
what stands out about their relationship?
and a planned pregnancy that resulted in an abortion.

Question: why did they have an abortion?
Self-contained rewrite: Why did Steven Tyler and Julia Holcomb have an abortion?