患者29岁，孕18周，于1993年9月27日入院。孕2产1，末次月经1993年5月22日，停经后1个月起有间歇性阴道流血，量时多时少，多时如月经量，色鲜红，无腹痛，自认为月经失调未诊治。人院前三天又出现阴道少量流血，自觉下腹部隆起而就诊，拟诊“中期妊娠”入院引产。月经史15岁天 The patient, 29 years old and 18 weeks pregnant, was admitted on September 27, 1993. Pregnancy 2 1, the last menstrual May 22, 1993, 1 month after menopause have intermittent vaginal bleeding, the amount of more and less less, often as menstrual flow, color red, no abdominal pain, that they did not diagnosed menstrual disorders. Three days before the hospital again a small amount of vaginal bleeding, lower abdomen conscientiously conspired to seek treatment, diagnosis of “mid-term pregnancy” admission induction. Menstrual history 15 years old