If homosexuality is, as they claim, genetic, then eventually that gene will be discovered and a test invented to detect it. If that happens, we will see if gays remain so pro abortion.
If there was a conservative gene, these pro-abortion savages will make sure no conservative comes out of the womb alive.
Will those who identify as gay support women who claim a right to abort babies they believe will grow up to identify as gay?
You've hit on a good point there.
There are actually a number of pro-life gays. The "intersectionality" of it tends to run along two lines:
(1) What you said. If we can ever test for the prenatal propensity to homosexuality, every potentially gay baby could be murdered before birth. Some gays have really taken this seriously and use it as an argument for gay/pro-life alliance.
(2)A critique of abortion as heterosexist violence. Some lesbians see heterosexuality as preponderantly abusive, and male-female intercourse as inherently assaultive (the radical Andrea Dworkin faction.) And some even see lesbianism as a way to decisively avoid both the violence of intercourse and the violence of abortion.
I think this point of view is profoundly warped, but it does show why some LGBT's are actually anti-abortion.