Can a man have a baby? Surprisingly, the answer is yes! But he wouldn't want to!
It is not yet possible to bring a baby to term outside a mother's body. Eggs can be withdrawn and fertilized, if a woman can't conceive naturally, but they must be reimplanted in order to grow. (But not necessarily in the same woman). After that, if the baby has problems, it can be taken out early. To date, the youngest premature baby that has survived was delivered after only just over three months in the womb!
But it is not yet possible for a baby to grow completely to term outside a human body.
But could a baby grow in a man's body?
Technically, yes. Here's how it could happen.
Obviously, a fertilized egg would have to be implanted in the man's body. This technique is already being done in fertility clinics for women who can't otherwise have children. The catch is that a man's body isn't designed to bring a baby to term, let alone deliver one(!).
The embryo normally makes its way (in a woman's body, after fertilization) to the womb, which is where the baby grows. A man's body has no such organ, but the embryo could be implanted somewhere in the abdominal cavity, and it would attach itself and grow. The man's internal organs would be pushed out of the way by the growing baby, but this normally happens in a woman's body anyway.
In fact, sometimes the embryo in a woman won't make it to the womb, but gets 'hung up' somewhere along the way, perhaps in the Fallopian tubes, where it starts to grow. This situation, called an 'ectopic pregnancy', is very dangerous for the woman. The lining of whatever tissue the embryo attaches itself to is not designed to support a growing baby. Normally, the lining of the womb will provide a strong attachment point for the placenta, and when the baby is born, it will detach and seal itself quickly, so the woman doesn't bleed to death. But other tissues do not have that property.
A baby's placenta, attached to some other tissue in the woman's body, or a man's, will detach very easily, and the resulting tear in the tissue will likely be fatal for the adult.
But not necessarily. Women have survived ectopic pregnancies. They have to remain immobile (lying down), be constantly monitored, and the baby must be delivered as early as possible by caesarian section.
With proper care, complete immobility, drugs to combat rejection, and hormones to make the man's body behave more like a woman's, it is possible in principle for a man to bring a baby to term, and give birth.
But it would be very dangerous for the man and the baby, and definitely prohibited on moral grounds.
