I have a perfectly healthy 20 month old who has tested negative twice. I will continue to check as she grows, but I saw not only my ob, but a high risk ob and my lyme dr all said that the risk of passing it on is very small. If you take the right precausions you will be ok. I have had lyme since 1998 and was on abx when I found out I was pregnant. You will likely be put on amox, throughout your pregnancy just to decrease any risk of passing it on, but I wouldn't let it stop you from having children. My daughter is perfect in every way and had I planned to wait until I never felt sick again, she wouldn't be here and I am thankful she is healthy.
Good luck. I am thinking of having another baby in the next year as well.