In abortion argumentation, a common attack against critics who are male is, "You're a man, you can't get pregnant, so you don't have a right to talk about it." Let's take a moment just to review why this argument simply doesn't work.
1) It's an ad hominem, plain and simple.
An ad hominem is often believed to just be an insult (like "You're stupid!"), but actually the Latin phrase itself means against the man. It refers to an argument that attacks a personal trait of someone giving the argument, rather than the argument itself. In this case, the response is not to the argument the man is making, merely the fact he is a man. It is therefore, at its very nature, a fallacious argument.
Let me put it this way: suppose I had a physical, and the female doctor inspecting me told me that it seemed I had testicular cancer, and that I should get treated or I might lose them. Would it make any sense to tell her, "Don't tell me what to do! You're a woman, you don't know what it's like to have testicles!" Of course not. I'm not responding to her arguments or any of her points - I'm just stating that she's a woman, as if that ends all discussion or completely negates what she just said.
2) It's inconsistent with other argumentation.
If a white person said, "I think the Jim Crow laws were wrong," would anyone stand up and say, "You can't comment! You're white!" Probably not. Likewise, one has to wonder if in a scenario a man supported abortion, how many pro-abortion people would jump up and say, "You can't say you support abortion! You're a man!" Probably none. Yet if you're going to make a kind of argumentation about one subject, you have to be consistent across the board.
The presents a good reason why this form of ad hominem is so fallacious: a moral or ethical question is not bound by the personal traits of the person giving it. A person does not have to be Jewish to say the Holocaust was wrong. A person does not have to be black to say the Jim Crow laws were wrong. A person does not have to have to be a kid to know child abuse is wrong. A person does not have to have lived under a dictator to know tyranny is wrong. Likewise, a person does not have to be a woman to say abortion is wrong.
3) It's not carried to its logical conclusion.
Let's say, for the sake of argumentation, that a man can't comment on abortion because he's a man and can never be pregnant. Who, then, can? If we say those who can get pregnant (ie., women), let's take that a step further. A woman who has never been pregnant could not comment, because she has not shared in all the emotional and physical experiences that come with that, therefore women who have never been pregnant cannot comment. Furthermore, a woman who was pregnant and had an abortion did not experience childbirth and all the positives and negatives that went with it, therefore she cannot give a valid opinion based on experiences. Even then, one would have to go through child rearing, raising a child through infancy, the teenage years, and through college to see if any one can go through that. Therefore, the only people who can ever comment on abortion are women who have had actual pregnancies, given birth to children and then raised those children through adulthood. That would not only take out a good chunk of pro-life advocates, but a good number of pro-abortion advocates as well. Sadly, I don't think many pro-abortion advocates would follow this logic quite this far.