Of course, your wife may never be on board and and only use her influence to stop you, as is the story of so many transgender people. Even wives who claim to be cool with it just as often change their minds and leave anyway.
Most ciswomen get married to have children, gain status, have financial support, have a protector, have someone to support and admire her, putting her and the children's needs above his own. Also, women are the boss of the home. They decide what is eaten, where you live, how the house the decorated, how holidays and free time are spent. Husbands spend every extra dollar and most free time in taking care of her, making her happy.
If you transition, most of that is turned around.
You will be the one spending large amounts of money on yourself for both medical reasons and for new wardrobe, shoes, jewelry, etc, instead of buying HER gifts. Your attention will be on yourself, and making YOU happy. You will have new friends, new interests, have your own life.
Instead of being big and strong you will be losing your testosterone advantage,
she'll be a laughingstock,
her children won't have a "father,"
her family and friends will pity her,
if she stays she'll be seen as a lesbian and blackballed from religious types, churches, etc.
You could start being attracted to men if you transition, as many do
you could make her-and your child- a target of attacks by religious fanatics
she will no longer be your priority and center of your universe.
But if you don't transition, dysphoria could push you to the brink, and you might lose her in the end, anyway. Besides, with a female-type mind, you might want your own life and no longer wish to devote every dollar and free minute on making your wife happy, or be submissive and obedient to her.
I have two transwoman friends, currently married, who have tried transition two different ways. One tried to keep her wife on board and her wife forced her to stop transitioning. It's been years.
The other is happily claiming that she will transition, move out, and start her own life, because her strict, religious Republican wife would kick her out if she even knew her husband was transgender.
But since she's not even told her wife yet after six months, I have my doubts she has that kind of courage.