At 38 weeks, your ready to go!
Ask him, he may suggest it! My Dr did it for me. I didn't ask, he just did it and IT HURT! It didn't do much for me, I was 1cm when he did it and went to L&D 4 days later to be induced since that didn't really work. I actually didn't have to be induced b/c i went into labor on my own. I was 2-3 cm when I went in that day. Did you have it done before? I mean it is quite uncomfortable, and you have cramping after words. But hey, maybe you will go into labor, and that is uncomfortable also, but the sooner its over the better right?