Women should have an absolute right to control their bodily integrity. We may not like their decision, but it is and must always be their decision. I'v collected a couple of analogies that make perfect sense to me.
Check out an excellent article here. Excerpt:
Our courts have always held that the government cannot compel an individual to use his or her body as an instrument for preserving people who are already born, much less for preserving a fetus in the womb. For example, the government cannot force a relative of a child afflicted with cancer to donate bone marrow or an organ to the child, even if the child is sure to die without the donation.
Obviously, if the state cannot force someone to undergo a bone marrow or organ transplant for a person already born, it cannot force a woman to continue a pregnancy that might entail great health risks for the sake of a fetus. As the Court of Appeals for the District of Columbia stated in a 1989 decision, "surely a fetus cannot have rights superior to those of a person who has already been born."
Another thoughtful article is here. Excerpt:
A second account of the abortion right, however, is the very different idea that no person should be forced to sustain another living creature with her body. The experience of pregnancy, on this view, is far too intimate and demanding for the law to mandate it of women, particularly when no similar physical altruism is generally required of men, who can choose not to donate blood or organs to relatives (or others) in need.
Far from demanding blood and organs from its citizenry, moreover, the law in this country protects even a dead person from compulsory organ donation. And this is true notwithstanding the fact that such organs - which will otherwise decompose in a graveyard or go up in flame -- could be used to save and preserve many lives.
When bodily integrity is so (perhaps excessively) prized, it must not give way just because it is the bodies of pregnant women at issue. If it does, then the law engages in invidious discrimination against women.
The connection to UltraRunning? I value my personal freedom beyond measure--the freedom to live my life as I choose, the freedom to engage in leisure pursuits such as UltraRunning, and--if I were a woman--the freedom to control my own body. It's all one logical whole.