Hello, It must be before 7 to 9 weeks before. We cannot definitely say the correct date. Because the sperm takes the time to travel and implantation may take some time. Thus the period interval varies. Hope this helps. Please write back for further queries. Wishing you good Health.

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Brief Answer: Not to say as impossible. if sex in ovulatory time Detailed Answer: Hello, We cannot say this is impossible. Conception after intercourse depends on when she ovulate. Fertilization can only happen after the day that she ovulate. When the egg comes down the sperm have 12 to 24 hours to fertilize the egg. If the egg is not fertilized then the egg disintegrates into your uterine wall and comes out with her period. Also since sperm can live a while in your uterus, 3 to 5 days if the sperm has female chromosomes, 2 to 3 days if the sperm has male chromosomes. Then implantation occur inside the uterus in next 3 to 4 days. If she had sex 3 to 5 days before her ovulation and 12 to 24 hours after ovulation, then chances of conception is very high. Hope this helps. Wishing you good health.

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