Paraphrasing the Zohar as cited in Hok l'Yisra'el, Vo'eira Yom Sheini Mussar section
Causing the death of the fetus causes sorrow in the world, and Hashem's Withdrawal. Pestilence and plagues are visited.
Praised be Israel, that despite the Decree of Par'oh to kill all the baby boys, none of the Israelites aborted their children. And Bizchut this, Israel merited the Exodus from Exile.