I sincerely hope and pray that you and your daughter will not decide to end the life of the little child who is growing inside her right now. Yes, what she has done is wrong in God's eyes -- but two wrongs don't make a right. While an abortion might seem like the easy way out for you and your daughter, it would be wrong, and in the long run she would live to regret it.
Life is sacred (even life in the womb), and is a gift from God that we must take very seriously. I know abortion is common today, and I'm afraid this has dulled our senses and caused us to ignore its consequences. But God sees things differently from us, and we turn our backs on Him at our peril. I often think of God's words to Jeremiah: "Before I formed you in the womb I knew you, before you were born I set you apart" (Jeremiah 1:5).
Admittedly, the months ahead won't be easy if your daughter carries her baby to full term. But every year thousands of childless couples are disappointed in their search for a baby to adopt, and I hope you and your daughter will prayerfully consider this option.
In addition, urge your daughter to look beyond the present situation, and to put her life and her future into Christ's hands. God loves her, and He wants to forgive her and help her rebuild her life on a solid foundation of faith.