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I'm sorry that your question wasn't answered in a timely manner. Although of concern, it's important to note that her bleeding can still represent normal physiology in a pregnant dog. Proestrus - the initial stage of the estrus cycle and the stage in which bleeding is first seen can last up to 17 days; estrus - the next stage in which bleeding can persist and when she should stand for the male can last up to 21 days. You can see, then, that bleeding could potentially continue for up to 38 days (5+ weeks) and be considered normal. Pregnancy doesn't stop the natural progression of the estrus cycle. (This is not the case in cats.) The only difference will be that a dog would be pregnant under the influence of progesterone rather than falsely pregnant (pseudopregnant/pseudocyesis) under the influence of progesterone as all unbred dogs become following their estrus cycle.
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