Here's an interesting article about the relationship of astrology and karma:
The reason that each of us inherits a unique natal chart is that the higher self selects a particular Astrological imprint, to experience certain events, and learn specific lessons. From this, an evolution occurs by processing karmic situations for optimum benefit. Situations, people and events in our life catalyze karmic growth, but the Karma lies within oneself, inside the Soul. The Soul is destined to be pulled to a particular birth, time and place.
The body is like billions of tiny solar systems. When you are born, every cell in your body adheres to the frozen picture of the planets at birth. It's like a circuit imprint that's formed at birth to be a reflection of one's Dharma (purpose and destiny) and Karma (debt).
We are all one with the Universe. The Universe beats from our point of view. The moving solar system allows for the Source to design its uniqueness in each one of us, and we absorb this imprint at birth. This solar imprint at birth is actually akin to tiny little solar systems in every one of our bodies.
Physiologically, at the moment of birth, the neurons of the brain form a specific pattern, which has been scientifically documented, and this sets up the personality of the individual.
So when you are born into any particular lifetime, you are born with a particular cosmic charge. This occurs upon inhaling that first breath, and reflects the planetary locations (Sun, Moon, Mercury, Venus, Mars, Jupiter, Uranus, Saturn, Neptune, Pluto), and the zodiacal sign that is rising in the East from your birthplace. These elements are the things that Astrologers can examine in a your chart and identify what your Karma is. For example, any square aspect you have, when planets are at right angles to each other, indicates your karmic debt.
Planetary placements that involve squares (right angles), oppositions (180 degrees) or inconjunct (150 degrees) and by house position will reveal a lesson area, an area where pain maybe experienced showing a pay back of karmic situations. The Karma that you have with yourself may concern money, love, relationships, career, business, goals, health, home, security of self, independence, enemies and all kinds of things. If you have squares in your life, this implies a debt, so the challenge is to overcome certain lessons we failed to learn in previous lives. Oppositions mean that you are born into a situation where you can create unrealistic goals, or, show catalyzing situations where you would create people in your life that may also manifest pain and karmic growth for you.
Understanding Astrology, by getting your chart produced, and tuning into things such as Karma and learning what the words square and opposition means, will help you understand which area of pain may focus the hardest with you. Your biggest Karma may be childhood, just fighting your way out of it, or trying to get along with brutal parents. This could be a way to understand where the peace needs to be made, and subsequently processed. It could be with your emotions, with your mother, friends, or with all of your relationships. It could also be with goals, career, communication, and finances. Astrology will help to identify your own personal map of Karma and it is a great way to rebirth into the Spirit.
Afflicted planets in a chart are those that form specific aspects, or angles, such as squares. A square depicts two planets, at right angles, with the Earth in the center (as center focus). Oppositions are when two planets are exactly opposite each other, with the Earth in the middle. You could be torn with the Moon in one point of the sky, and if you drew a straight line from the Moon to the Earth, and all the way threw the Earth to the other side, you might find the Sun. This would be a Moon opposition Sun. These might be planetary aspects that you're born with. With squares, or oppositions, these diagrams are Karma, or the debts we owe for a particular lifetime. Everybody has Karma whether your born Karma free or not. Without any squares or oppositions in your chart, the moving planets form squares and other aspects to the fixed position of natal planets during ones' life (which is the basis of forecasting). This daily movement with respect to the natal chart is known as transits.
The signs of the Zodiac are magnificent stellar constellations. When we say that you have Mercury in Cancer or Gemini, that means that Mercury is located in space in the stellar constellation or grouping known as Cancer or Gemini. That's how we identify energies at birth, freezing the planets that are moving in space, through the signs, during your birth. There are all kinds of stellar constellations out there in space; The Sun, Moon and the planets, follow an orbit called the Ecliptic—which is a flat orbit. The Earth also orbits the Sun along the Ecliptic, so the planets including the Sun and Moon, do not wander beyond the twelve Signs of the Zodiac.
One of the main factors in distinguishing a karmic lesson is Saturn, as this planet is the lord of Karma. If Saturn signifies obstacles and limitations in life, it is because either your desired goal was incorrect, or a karmic reaction has been imposed. As such, Saturn's placement in your chart can indicate the areas in life that one needs to work on. Saturn's movement with time, through your natal chart, induces various scenarios to force growth in certain directions. When we ignore our real goals, certain crises' can occur in adulthood as Saturn orbits the Zodiac forming particular stressful aspects to the natal chart. Therefore, if you fail to conform to certain ways in this life, Saturn is always there to induce a karmic lesson, either immediately or in the future.
Saturn remains in one Zodiac sign for an average of two and a half years, so a whole karmic generation of Saturn people enter life during that two and a half year period. For example, people with major karmic lessons concerning Sagittarius energy and forces (meaning freedom happiness, philosophy, travel, sometimes sports, and animals) form a Karma here. It takes Saturn about twenty-nine years to circle the Sun, from our point of view, covering all twelve signs of the Zodiac. The type of Karma that each baby will have during the two and a half years of Saturn in any sign, although similar, will further depend on its aspects to other planets, the location of the house, and whether it's retrograde or not (Saturn retrograde tends to open up the energies of Uranus).
Read more on : Karma and astrology
My personal opinion on this:
Lately, I've been thinking about karma and how it can affect our life. I do believe that somehow, there's a reason we are what we are right now and it's not because of some random pickings from above. Some believe that our soul have chosen this path in this lifetime...others seem to think that our life is like a tabula, that all we have is now, and we should live by the moment. Astrology and karma do seem to be connected. As complicated as it is, I don't usually dwell on it too much nor try to research for the causes of what I am right now...I prefer moving forward. Knowing is already a privilege I appreciate.
I believe that somehow our soul have chosen this lifepath for a purpose...and it is hard to distinguish now...maybe when we become wiser...if we open our minds and see possibilities, lessons rather than obstructions and hardship, we can see the wider view of life. There is also freewill, we are not stuck in this string of complications at all...we always have a choice and the good news is...we control our life. Even if we're slaves or mere workers, we chose to follow...but we can also choose not to. The hardest part is taking the blame for our own actions. I guess it is a natural reaction because it does affect our psychological being. So I worry about people who think that they can't change what they are now and they cannot do anything about it....If we dream and strive hard to achieve them, we can.