why does having a baby affect men so much?

A man wants his girlfriend to be attentive towards him and her go out for an enjoyable time. The relationship might get serious and the man will hope for a great time. He might not want to be tied down. The words "I'm pregnant" could come as a shock to him. In a few months his girlfriend will develop a bump and before then have pregnancy symptoms like sickness and tiredness. The thought of the birth might feel the man's mind with dread. It is not like a holiday when the departure day is known it could be like a mine field because the day of the birth could be anytime, hopefully 38 to 40 weeks but possibly before then. The lady might buy lots of baby stuff and the man might feel less loved. When the baby is born the man might feel unable to hold his son or daughter in case he dropped him or her through his nerves. Over a period of time hopefully the man will adapt into being a good father.

That because men have often less experience with children than women. If we look to our society, only women who do practice childcare skills, throughout life as big sisters, babysitters, volunteers. Boys are offered fewer such opportunities, for this reasons, some men are initially less comfortable with less skilled in caring for children. And also men tend not to feel the same social pressure as women to learn to care for their own children...the more the mother does parenting, confident, and the more they learn more, the more the father does less, learn less, and feels less capable of providing daily care...which is very understandable...

I dont think some of them like to have too much responsibility.. or like to be tied down. . I could speculate farther but i may offend someone. . .

It is probably a normal thing that goes hand in hand with the fear of becoming a father for the first time and they have to come to the realization that they are expected to step up and take responsibility. Some fathers run away from things like becoming a dad and some men are very good at being supportive. There might be more good men out there then some people realize. It is not easy these days to be a mother or father.