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It is recommended to use protection while being on your first pack of birth control pills. The protection starts completely after you start with the second pack. Since the ejaculation did not happen, chances of pregnancy are less, but cannot be ruled out due to pre-cum (pre-cum or re-ejaculatory fluid is known to contain sperms). Visit your gynecologist for a thorough examination and further tests if you develop any new symptom suggestive of pregnancy or suspect being pregnant. Wait and watch for periods while on the placebo pills.
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