I certainly don't think you can conclude that these aspects of pharmakeia were OK because they were not specifically singled out and condemned. I must add that what's comprised by the inclusive term pharmakeia would be relevant to this discussion.
What we do know, is that nether is ever shown to be blessed by God: on the contrary, life and fertility are praised; opening and closing the womb are prerogatives of the Almighty as Lord and Giver of Life.
Devoted to Scripture as you are, you must have noticed the exceptionless themes in the Bible of both the blessedness of life and the blessedness of the marital relation as a sacred fertile union under the providence of God.
The Biblical line of reasoning against abortion is identical to one one against contraception.
I conclude what I already stated. God's word commands us to abstain from sexual immorality, adultery, fornication and murder. Do you think this doesn't apply to the issue under discussion? Having sex with someone NOT your spouse is prohibited. Using any kind of contraception that causes the death of the unborn is prohibited - certainly abortion falls under that. When the BC pill first came out, it was restricted to married couples (the Comstock Act). No one really was told the pill's hormones had a secondary effect that if a fertile egg was released and fertilization happened, the embryo/zygote was prevented from attaching to the uterine wall essentially causing an abortion. It was quite nefarious that the drug maker didn't clarify that point or tried to hide it. When this fact became more widely known and the other harmful effects of the hormones came out, many, many women stopped using the pill. Information about the IUD was more informative and it's main function was specifically to make the uterine wall repel an egg from implantation. I certainly think more information should be given to women about these products. If they knew what they were using directly or indirectly caused expulsion and death of an embryo, perhaps they would not use them.
If you want to use the Onan story (as Catholicism does) to condemn withdrawal, then you ought to also know that most Bible scholars believe God's judgment of Onan was about his disobedience to father a child in his brother's name with his widow and he refused. That makes more sense to me that a blanket condemnation of using withdrawal as a method - though highly ineffective - to prevent pregnancy.