retaking IB without a valid reason?

<p>Could anyone tell me whether Harvard takes into account IB retakes without an excuse?
My reason for retaking was because I thought I could do better, but I don’t know if it is worth it if universities don’t consider retakes unless there is a good reason. I was 4 months late coming to school the first year and this definitely affected me, but I think that is not a valid excuse to retake.
Thanks in advance, I am deliberating whether to retake or focus all my time on my ecs and I would really appreciate help as gaining admission to a need blind school is important to me.</p>