I agree with everything that Dave says, and would add a couple of more points which I hope will be helpful.
While the study of Karmic Relations, as outlined in the many books of Rudolph Steiner (the late German philosopher and psychic) involves multiple past lives and their interaction with the past lives of others does involve more-than-one-person, such a study using Astrology would be difficult unless any suspected past lives of individuals had birth times/dates recorded in historical records.
In any case, I would not offer any deeper statements than these. I have not seen any on this list who have indicated an expertise in this area. I would feel most comfortable sticking with plain old relationship studies. Dave
I'd just emphasise the burden of the first paragraph but in a wider context. I don't think any chart comparison is worth the effort
unless there has been a thorough examination of the two natal charts individually (which I think is implicit in Dave's point) so that would be your first step.
Karma has a long long history as both a religious and philosophical concept in Hinduism. It is rooted in the culture and history of the sub-continent. I'm always wary of approaches which 'cherry pick' 'attractive; concepts and put them into Western Astrology. So if I were seriously pursuing information on my Karma, I'd consult a Vedic Astrologer.
Dave mentioned one or two features of the Western approach to Karma in Astrology and these include the use of more planets than the now generally used ten. Indeed some Karmic Astrologers use all or some of Sedna, Chiron, Quaorar, Makemake, Orcus, Eris and Haumea. Whilst I'm sure Dave would argue for the exploration of these planets (Astrologically speaking) I'm reasonably content that he would not say we have unquestionable delineations of their meanings. I would go even further and question whether they
have any meaning. It's up to their users to demonstrate consistent and widely agreed meaning. So at the moment I don't think that the Western approach to Karma in Astrology is something that can be taken as clear or certain.
That being said, if you want to get a reading then do so, try at least three different Astrologers and see what common themes they pick on. For me the problem, as Dave points out, is the lack of knowledge about the previous life. However you can try psychics, or even past life regression as supporting lines of investigation. This should leave you with perhaps half a dozen readings from more that two divinatory systems which you can mull over and compare and pick out any common themes, especially ones that appear in say five out of six or even all six readings. And don't forget talking to a Vedic Astrologer. They operate within a cultural setting that is used to dealing with issues of Karma and has done so for several thousand years.