Congrats on the pregnancy! And I can say from our experience pregnant women are sooooo sexy! We would definitely not be turned off by it. We were not into the scene when we were pregnant, but since have played with 2 that were and also lactating. I myself love to play with milking breast. it is just something very unique.
But as was mentioned previously... be sure to still use protection if you do decide to swing, you are very susceptible to infections and can cause issues with the baby. But other than that... enjoy the extra hormones!! And if you are in this area... you have a willing play pal here to help you with your lactating...