Not a mother, but my take as a childfree woman:
I see horror stories a lot online, as well. But in real life I have some fantastic mom friends that still have great bodies and wonderful relationships with their husbands. My sister has a 2.5 year old. She is still in good shape and has a great marriage, they are working on their second now because of how much they enjoy being parents. There are also numerous actresses and fitness celebrities who are moms and have bodies and looks that childless women envy.
I also know some women in real life who have completely let themselves and their marriages go following childbirth and are completely miserable. But from what I observe, it's not because they had a child; it's because of what they did, or rather did not do, afterwards.
Yeah, there's always a possibility of something going wrong during childbirth. That's just a gamble you take when you have children, though. I think the above suggestion of talking to an OB/GYN is a good one.
But if there is one thing that I see, is that intimacy with your spouse does not have to stop because you have children. If it did, there would be a lot of people out there with only one child.