When our soul prepares to reincarnate, we are told what we did in our immediate past life and what work still needs to be finished. We are told what our higher soul needs. At the moment of conception (whether it happens in the traditional way or in vitro), the soul sees the puzzle in its entirety and chooses to take on a particular incarnation, realizing that this is what it needs in order to grow.
But why would a soul choose to be born into overwhelming difficulties, such as disease, abuse, or abject poverty? While it's still a spark of Light, the soul looks down on this world much like a satellite views the earth. From this vantage point, it can observe not only where it has been, but where it needs to go and what kind of environment will help it finish its correction. The soul identifies the people and circumstances that will help it complete its particular process and then chooses that environment to come into.
The consciousness of the new baby's parents also contributes to the process of determining what type of soul they will attract to themselves. For instance, if a man has sex with another woman and then comes home to sleep with his wife, most likely his thoughts will be somewhere else. Still, he may have sex with his wife out of a sense of duty or guilt. Maybe he's not really into this relationship, or maybe she isn't. Those feelings or lack of feelings-that particular state of consciousness-attracts a soul that needs exactly this setting.
The soul that chooses to be conceived at that particular moment and born to that particular couple will have a corrective process that involves a challenge with parents or relationships.In a former life, this soul may have done something that broke up its family or it may have been a philanderer. To correct that aspect of itself, the soul comes into a home where there is discontent, dissention, or even depression. The soul actually sees this couple's consciousness, recognizes that this difficult relationship will be good for its tikkun (the Hebrew word meaning "correction," which is also understood as karma), and chooses to be born into it. The consciousness of the parents helps define the circumstance. The soul may be brought into this particular marriage as a child born "by accident." The couple may have not necessarily wanted a child, but nonetheless, one was conceived. But whatever environment is chosen, it is always the unique soil in which the seed of our soul needs to be nurtured.