It is certainly an obstacle to overcome, but also certainly not an impossible one. There are a few strategies to address your low score on Step 1. First will be to show that the result was an aberration and not at all indicative of your academic history and abilities. The way to accomplish this is to get as high a score as possible on Step 2 CK (and also Step 3 if you have time to take it before you apply) and to pass Step 2 CS on the first attempt, if you have not done so already. Additionally, show academic determination in all your rotations. Because Ob/Gyn is a primary care specialty, in addition to a surgical one, nearly all other specialties relate to it. In every rotation, make yourself known for asking questions; researching answers, unusual presentations and latest techniques; finding empathetic and personalized ways to educate patients and their families on the diagnoses and treatment plans, etc. Get involved in research if possible. In other words, take a holistic approach to the question of your academic talents and abilities via both learning and educating others.
Additionally, look to excel in the nonacademic aspects of the field. This includes, for example, building rapport with patients, bedside manner, communication with patients, their families and fellow medical staff, being a reliable team member who others enjoy and want to be around, developing your surgical skills, etc. In other words, develop all aspects to the best of your ability to shift the focus away from the low Step 1 score.
Accomplishing these goals would also help you with getting strong letters of recommendation and give you a rich collection of content to use for writing a compelling personal statement.