A 28-years-old primigraida was referred at 31st week of gestation for a targeted ultrasound examination following isualization of a seere hydramnios.Fetal biometry was consistent with gestational age.

• 一28岁初产妇，孕31周时定向超声检查发现羊水明显的增多，胎儿生物学检查符合孕周，为男性胎儿。