Normally, pregnancy can be detected 7-10 days after the fertilized egg is laid. Clinically, a blood test for HCG in the blood or a urine test for the presence of HCG in the urine is required to determine if the patient is pregnant. The placenta will not secrete HCG until at least one week after the fertilized egg has been laid, at which time a blood test or early pregnancy test can usually determine whether the patient is pregnant. After the fertilized egg is laid, a series of symptoms will appear in the body, such as chest distension, nausea, vomiting, and some patients may experience a small amount of vaginal bleeding or mild lower abdominal pain. Patients should pay attention to rest and nutrition during the period, and remember not to overexert themselves or do strenuous exercise.