Just about every guy who goes through this knows exactly what I am talking about, and it is a feeling unlike any in the world. However, once these elated feelings fade, as is only natural, a lot of your fears start to creep up on you.
This happened to me after a couple weeks into my wife's pregnancy, when we found out one of her friends who was pregnant around the same time as her, had a miscarriage. It was at this point time that I realized that bad things could happen to my baby, and I had a big shift in the way that I thought. In the beginning I wanted to have a boy, but I no longer started to care any more about the sex, and I just wanted to have a healthy baby. You start to realize that there are more important things than the sex of your baby once it finally hits you that you are in fact having a child of your own. There are so many things that you will worry about during your wife's pregnancy, that you will absolutely drive yourself nuts if you don't learn how to handle these things in a cool and calm manner.
There are a battery of tests that your wife will have to go through while she is pregnant, and each one of these are usually standard protocol and nothing for you to worry about. However, when you are going through your first pregnancy it is quite difficult not to worry so much, as it is an experience you have not been through before. You have to realize that you are now having a baby, and it will grow into an adult, and with them, a number of worries over the next 15, 20, 30 years or more.. So it is best that you learn in the very beginning how to handle all of the stress, because it is not something that is going to go away once your baby is born.
Source: ezinearticles.com