Here is one of the best quotes I've read in a long time; it's by Courtney Reissig, writing at Christianity Today's "Her.Meneutics" site:
Children are not a death sentence to our ambitions and goals. They may change them, postpone them, or even make them more difficult to attain—but they are always a blessing. We don't earn the right to stay home or have children only after having done something important with our lives. We earn the benefit to have children simply by being created in God's image.
Preach it, sister. Career dreams, professional attainments, academic achievements: All that are done for the glory of God are good and noble things. But to place children in apposition to them is a false alternative. I'll let Mrs. Reissig have the last word:
Children also come to us -- biologically or through adoption -- at God's timing. Despite my desire to start a family earlier, I didn't give birth to my twins until I was 30. Even when we are open to having children, it doesn't always happen right away and sometimes, they don't come at all. But the church should be a place that welcomes expectant mothers regardless of what they have accomplished pre-pregnancy. Even if she never finishes her degree, lands a top client, or wins an Academy Award, bringing life into the world is a beautiful and God-honoring thing.