The pins and needles sensation in the abdomen during the seventh week of pregnancy may be caused by physiological reasons, preeclampsia and ectopic pregnancy. 1. Physiological reasons: after pregnancy due to the increasing uterus on the surrounding ligaments of the pull can be caused by a slight pain in the lower abdomen, similar to the feeling of pins and needles, not accompanied by vaginal bleeding and other symptoms, ultrasound embryonic development is good, progesterone and blood HCG (human chorionic gonadotropin) levels are normal, is a normal physiological phenomenon. 2. Pre-eclampsia: small amount of vaginal bleeding, dark red or brown, may be accompanied by paroxysmal lower abdominal pain, making the abdomen feel pins and needles, ultrasound suggests intrauterine pregnancy, progesterone and blood HCG levels may be low, combined with the clinical manifestations and laboratory tests can assist in the diagnosis. 3. Ectopic pregnancy: because there will be some hidden pain in the lower abdomen and can be manifested as pins and needles in the abdomen, may also be accompanied by irregular vaginal bleeding and history of menopause, through ultrasound, blood HCG can assist in the diagnosis. Seven weeks pregnant with a pins and needles sensation in the abdomen need to go to the hospital in order to identify the cause, and timely treatment.