This is an intensely personal matter. I won't offer advice other than to tell you that the older I get the more my family, especially my direct descendants, means to me. You need to decide what your priorities are because, once you have a child, that child is Priority 1 24/7.
Do you have friends and/or family who can help with child care? I think that will be necessary if you're going to finish your degree and write your thesis.
Best wishes.