You know, I think about this all the time. If I had it to do all over again, would I choose to bring a little life into my family. The answer is yes, every single time. I never knew love, real honest, true, lay down my life love until my blind date with my daughter. The day they handed her to me, was the greatest day of my life. I felt like God had decided to bless me and my life and our family. While some days are harder than others, I would never trade this feeling for anything in the world. While as hard as it is to be a parent, the reward of it out-weighs any negative you might find.
If "you" (not the OP, just generalizing) are a selfish person, then I am not sure I would opt for a kid. Once you bring another human being into your world, it is no longer about you and your life. You now live for that little baby. If "you" enjoy private time, sleep, going out, having friends, being clean, and many other things, lol...I would tell you to think twice. I no longer have private time, nights of sleep, sleeping in, dates with 2 AM, my original group of friends, or the 30 minute showers anymore. My original group of friends gave up on me once they realized I was no longer able to go out and "party" (Extremely pleased they are no longer a part of my life). I no longer get time to myself. I find my time goes to cleaning, laundry, washing bottles, or whatever else has piled up because my time is spent with my little lady love. I am okay with not having time to myself, because she makes it all worth it. When I said I lost my friends, I have since gained a different group of friends, which I love dearly. They are now known as my friends with little ones or AKA "Mother-friends"!! Again, I am okay with the different group I now regularly hang with. They are all about their little ones in the their life as well and could care less about that party life.
The last few things I want to note.....
I don't care how amazing of a marriage you are in, or how crappy of a marriage you are in.....babies are a lot of work, a lot of give and take, a lot of sleepless nights....lack of sleep causes tempers to run short, and in turn brings on arguments. Be prepared. Perfect marriage or not, you will fight, about stupid stuff that has zero baring on anything....just because. Babies add strain to marriages at least for the first few weeks/months. It is hard work. It isn't a walk in the park....but it is worth it.
Lastly, make sure you are financially able to take care of a child. Make sure you have room to wiggle if things don't go as planned. By that, I mean....make sure you can afford formula if breastfeeding doesn't happen to work out. I mean, why on earth would you buy formula when your body produces free food for your child? Well, to be honest, sometimes, you can't help it. Sometimes, it just doesn't work. Hence, wiggle room. Everything doesn't always go as planned, and if it does, kuddo's to you for being the worlds only person to have everything fall in place in your life all the time. Kuddos!
Those are the things I can say about bringing a small itty bitty into your families. I don't think you can mentally be prepared for it ever, even after said little ones arrive. It is forever a learning process, but a fun one! Good luck in your decision.