With respect to elevating scores through multiple sittings of the MCAT, the AAMC reports the probability to be low. Nevertheless, the task is not impossible. In fact, several consecutive sittings of the test may favor improvement, since the bulk of the material and the strategy necessary to tackle the questions does not vary intensely. Essentially, the Verbal Reasoning requires the same attention and detail while the Physical and Biological Science sections will draw questions from the same themes as seen in previous tests.
One important consideration, though, is the acceptance of osteopathic or possibly even foreign education. As said previously, revisiting options will clarify the magnitude of a desire for a medical education. A D.O. and a foreign M.D. will establish the right to see patients as well as an allopathic degree from an stateside school.
A more potent, yet relevant, concern toward retaking the MCAT is the notion of losing time and resources for a coveted score. By attaining a 39 MCAT alone, admission to any one school is not guaranteed by that single criterion, despite the favorable reception thereof by some committees that will grant the highest score. Others may take a composite score. Nevertheless, even an admission to a stateside allopathic program after maybe months or even years in pursuit of a score (I am merely setting forth a hypothetical) will not compensate for the time lost or money spent on transitioning oneself into that position. The time is lost and cannot be regained to repeat prior ambitions. This notion is valuable to contemplate because a medical career inflicts physical rigor upon the student, resident and fellow that is more easily met by somebody in his or her late twenties versus late thirties.
Hence, no prolific solution resolves this conundrum. The key toward resolving this problem is to gauge one's risk aversion profile and hold no expectations. If one is willing to take the risk of spending time and resources for the purpose of a higher score, then one must be willing to lose the time and even money only to realize that the endeavor is void of any fixed outcome. Conversely, if one is prepared to go to the Caribbean or DO school, then one must be willing to surrender the ambition to attend a stateside allopathic school. Each has risks.
Since no assurances prevail, risks must be taken. I will say that people have taken the MCAT multiple times before and witnessed an increase in their scores to enable an admission to allopathic programs. These same individuals did well on boards and in surgical residency and fellowship. These same chaps also said it was not easy, yet nothing worthwhile ever is. Remember, though, that retaking the test will not please everybody, thus forcing diversification of applications.
If one really has the passion, then retake the test but do not hold expectations on the forward result. Expectations will suppress the momentum of progress or even intimidate the acceleration of studies.