I'll clue you in to the worst things about both. They are the wedding and the pregnancy - or specifically the preparation for the wedding and the nailbiting, crossing-off things that can be wrong with it part of the pregnancy.
Weddings can be very stressful. Even if you're a "yes dear, it's your day" husband-to-be, which I don't recommend (there's two of you - the day is for both of you), watching her get more and more wound up planning ridiculous things that you can't see the point of and making it more rigidly scheduled than a Japanese railway timetable - and paying for it - are killers. The most recent two I've been to - mine and daan's - were complex in their own ways (ours was ten thousand miles away and most of the preparation was done by Smallhorses and itgirlxx; daan's was more formal and there were kilts and a ceilidh) but struck the balance right. We all enjoyed both of them.
Pregnancy is a rollercoaster of risk. Every day is a disaster waiting to happen - even before you start. Folic acid, runny eggs, caffeine, alcohol and soft cheese become murder weapons, every twinge you get every day suddenly becomes "a problem", every scan and every test is an attempt to find something wrong, she stops eating for a month and occasionally passes out, then she eats enough for three and occasionally lashes out. We haven't even got to the birth yet - which in our case will be scheduled major abdominal surgery with an alternative of death - and then there's the infant years. A general surgeon friend of mine remarked that he hated paediatric medicine because not only do the kids not tell you what's wrong (because they can't), but they also exhibit almost no symptoms of illness whatsoever up until the point they've died from it...
Being married and having kids are each well worth it, whether you do one or the other or both. The lead up to either is a nightmare.
Oh, and if you're preparing for either and asking yourself those questions, run. Run for the hills. Don't look back and don't even pick up your clothes.