This can also be done prenatally by testing fetal DNA obtained through either chorionic villus sampling or amniocentesis.

这可以在产前通过检测胎儿DNA完成，如绒毛膜绒毛取样或羊膜穿刺术。

Diagnosis is by echocardiography and can be done prenatally.

超声心动图可确诊，胎儿期就可以做。

When diagnosed prenatally, Hb Bart's hydrops fetalis can be treated with intrauterine transfusions and later followed up with bone marrow transplantation.

如果在产前确诊，Hb Bart水肿胎儿可通过宫内输血治疗，随后进行骨髓移植。

" My son has a heart who is one with a heart defect, we knew prenatally about it through a series of tests" .

" 我儿子的心脏有缺陷，我们通过一系列测试在产前就知道了这件事情。"

The majority of cerebral palsy cases are thought to happen before birth, or prenatally, which typically means the underlying cause is really hard to pin down.

人们认为，脑瘫的主要病因发生在出生时或产前；通常，原因很难确定。

Cerebral palsy doesn't have to happen prenatally, though, and some postnatal causes are things like head trauma, or again an infection or a period of oxygen deprivation.

不过，脑瘫不一定发生在产前，还有一些产后原因，如头部外伤，或感染，或缺氧等。