To me, killing is killing no matter how it is explained. The pregnant lady knowing very well that if she is caught, they will bring her to the hospital and abort the child whether she wants it or not. Even if she got pregnant without knowing, it is still killing as she is the reason that the baby have to be killed. The karma will still be on her, the baby and the officials that were involved. Directly or indirectly.
http://www.buddhanet.net/fundbud9.htm (read more about it here)
Karma, be it wholesome or unwholesome, is modified by the conditions under which the actions are performed. In other words, a wholesome or unwholesome action may be more or less strong depending upon the conditions under which it is done. The conditions which determine the weight or strength of karma may be divided into those which refer to the subject - the doer of the action - and those which refer to the object - the being to whom the action is done. So the conditions that determine the weight of karma apply to the subject and object of the action. Specifically, if we take the example of killing, in order for the act of killing to have its complete and unmitigated power, five conditions must be present - a living being, the awareness of the existence of a living being, the intention to kill the living being, the effort or action of killing the living being, and the consequent death of the living being. Here too, we can see the subjective and the objective conditions. The subjective conditions are the awareness of the living being, the intention to kill and the action of killing. The objective conditions are the presence of the living being and the consequent death of the living being.
Similarly, there are five conditions that modify the weight of karma and they are persistent, repeated action; action done with great intention and determination; action done without regret; action done towards those who possess extraordinary qualities; and action done towards those who have benefited one in the past. Here too there are subjective and objective conditions. The subjective conditions are persistent action; action done with intention; and action done without regret. If one does an unwholesome action again and again with great intention and without regret, the weight of the action will be enhanced. The objective conditions are the quality of the object to whom actions are done and the nature of the relationship. In other words, if one does a wholesome or unwholesome action towards living beings who possess extraordinary qualities such as the arhats, or the Buddha, the wholesome or unwholesome action done will have greater weight. Finally the power of wholesome or unwholesome action done towards those who have benefited one in the past, such as one’s parents, teachers and friends, will be greater.