It automatically follows that abortion should not occur just as it automatically follows that innocent people should not just be killed.
The mother knew beforehand that a pregnancy could very well occur. The mother gave this human life. I don't think that means she should be allowed to just take it away. Children drain their parents resources for some 18 years as it is.
As for the other thing. I don't know. It is an interesting hypothetical about how much you really owe to those around you. Then again, in the case of pregnancy the analogy breaks down as I did not create the person's life. I still don't know though. Thank you for giving me someting interesting to think about.
The question is if the mother is killing the child in the way that we usually use the word. The fetus is unable to maintain life outside of the womb. Thus, it is not reasonable to equate abortion to stabbing a stranger on the street. By aborting, the mother is simply not allowing the fetus to use her resources.
You bring up the point that the mother knew pregnancy could occur. In most cases, I would agree that this is true (sadly, I do not believe some realize that no method of birth control is 100%). To give a few other hypothetical situations, then:
1) You agree to let your younger cousin to come live with you, as he has nowhere to go -- ie, to use your resources. Once there, however, he begins to wreck havoc on your life. He eats all of your food [without your permission]; he is abusive towards your boyfriend/girlfriend, causing a strain in your relationship; his behavior, on numerous occasions, causes you to miss work; and so forth. You want to kick him out -- ie, to prevent him from using your resources. Of course, you knew there was a small chance that he could behave like this; however, you did not agree to him behaving like this and most would still say you have the right to kick him out, even if it means he would be homeless.
To bring this back to abortion, when someone has sex, they likely know that there is small chance of pregnancy, birth control or not. That does not mean a woman consents to being pregnant, however. If the egg fertilizing is the equivalent of your cousin coming in to live with you and becoming disruptive, and you believe that you have a right to kick your cousin out, why does the women not have the right to stop the fetus from using her resources?
Once again, it may be nice if you tolerate your cousin or the fetus; but are you obligated to?
2) A lot of things carry a known risk to them; however, that does not automatically mean that if a person engages in said risky activity that they automatically must endure the consequences. For example, when you walk outside, there is a small chance of you being attacked. You know there is a risk of that happening. Yet, most would say that you still have a right not to be attacked.
When a mother chooses to raise a child, she is allowing that child to use her resources. There is no force.
a) No. Just as, to give another scenario, if I were the only plastic surgeon in a 50 mile radius and a woman asked me to give her a breast augmentation, I would refuse because I think cosmetic surgery is asinine. Obviously there are differences between abortion and cosmetic surgery, but the two scenarios are similar in several ways in my eyes. Neither (again, assuming otherwise healthy individuals) is medically indicated, and by refusing to perform the procedure I won't be putting the patient in harm's way. The patient would be inconvenienced, sure, but inconvenience isn't enough to obligate me to ignore my own values and support the patient's in my opinion.
a) But the patient
would be in harm's way. Using high blood pressure as an example, there is a whole list of complications that can arise from it. By refusing the patient an abortion, she is in harm's way.
b) Though I would not consider the two equivalent due to my opinions on abortion (see above), I would also ask why the women wants an augmentation. If she was in the same distress, I would argue that, yes, you would be putting her in harm's way. I would also ask what the difference, in the case of augmentation, is between the women seeking it with health problems and the women without. Both are motivated by similar emotions.
b) I think the hypothetical you're mentioning is highly unlikely. Regardless, if a pregnancy was causing legitimate, life-threatening harm, then yes, I would refer for (or, if absolutely necessary, perform) an abortion - as a physician I must put my patient's health in front of my own values. Elective abortions in the case of unwanted pregnancies due to consensual sex don't fit that bill in my opinion.
As in the case with these situations -- that, yes, are unlikely -- it is consensual, unwanted and posing a health risk.
c) I think the main argument supporting abortion in the case of rape is that the woman was impregnated through no fault of her own and presumably refused sex. As a result, she's saddled with a burden that she shouldn't be responsible for, and it's highly unfair that she should have to provide care for a child while the father sits in jail unable to contribute to the significant costs of child rearing. I think that's the most compelling argument supporting abortions in rape cases.
Understood. Is there anything in particular causing you to hesitate, then?
Edit: Just to be clear, I do not see you as being inherently unethical for refusing to perform abortions. In most cases, I do believe in physician's choice as well as the patient's.
congratulations 
