Final answer:
It is typically too early to determine pregnancy one week after intercourse through symptoms. However, the possibility of conception exists if unprotected sex occurs near the time of ovulation. Implantation bleeding and the timing of ovulation play a significant role in the early detection of pregnancy.
Step-by-step explanation:
Understanding Early Pregnancy and Ovulation
Determining early pregnancy within one week is typically not possible through physical symptoms alone. It's too soon for the common signs of pregnancy to develop, which often include a missed period, tender nipples, increased appetite, and more frequent urination. These symptoms are generally observed in the first trimester, which covers the first 12 weeks post-fertilization.
If a female experiences unprotected sex on a Saturday night and then feels mid-cycle pain indicative of ovulation on the following Tuesday, her concern about becoming pregnant is valid. Sperm can survive in the female reproductive tract for up to 5 days, and ovulation following the unprotected intercourse is within this time frame, increasing the chances of fertilization.
Regarding the scenario of experiencing minor bleeding and cramping about 3 weeks post menstrual period, this could potentially be implantation bleeding, which occurs when a fertilized egg attaches itself to the lining of the uterus. This is often accompanied by light spotting and cramping and is one of the earlier detectable signs of pregnancy.
It is important to note that pregnancy tests are the most reliable method for determining pregnancy, generally providing accurate results around the time of a missed period, which could be around two weeks after ovulation and potentially fertilization.