How many days after conception can an ultrasound confirm an intrauterine pregnancy?

Under normal circumstances, an intrauterine pregnancy can be confirmed by ultrasound between 7 to 10 days after conception. The detailed analysis is as follows:

Intrauterine pregnancy refers to the implantation and development of a fertilized egg within the uterus. Normally, approximately 5–6 days after implantation, the embryo begins to secrete human chorionic gonadotropin (hCG), a hormone detectable in a pregnant woman's blood and urine. The concentration of hCG gradually increases after conception and can generally be detected via blood tests or ultrasound between 7 to 10 days after conception. Ultrasound is a non-invasive imaging technique that uses sound waves to observe and diagnose internal body structures. To confirm an intrauterine pregnancy, ultrasound is typically performed between the 5th and 7th week of gestation. During this period, the ultrasound can detect the presence and size of the gestational sac and visualize the embryo and fetal heartbeat. By measuring the diameter of the gestational sac and the size of the embryo, doctors can estimate gestational age and assess embryonic health based on the presence of a heartbeat. Additionally, ultrasound can evaluate the shape and structure of the uterus, helping to rule out complications such as intrauterine abnormalities or ectopic pregnancy.

It should be noted that in certain special cases, such as endometriosis or uterine fibroids, ultrasound results may be affected, potentially leading to less accurate detection. In such situations, doctors may consider the patient’s medical history and other test results to determine whether additional examinations are necessary.