It can be concerning when there is no visible fetus at 7 weeks of pregnancy, especially if you have previously had a miscarriage. There are several possible reasons for this late growth or lack of fetal development. One possibility is that your dates may be incorrect, and you may not actually be as far along in your pregnancy as you thought. Another possibility is an ectopic pregnancy, where the fertilized egg implants outside of the uterus. In some cases, it could also indicate an impending miscarriage or a blighted ovum, where a gestational sac develops without an embryo inside. It is important to consult with your healthcare provider who can perform further tests such as ultrasound and blood work to determine the cause and provide appropriate guidance and support during this time.