If an infant is born alive ...or "premature baby," not "fetus."

"prematurely"是副词，意思是"未成熟地，太早地，早熟地"。 本句应译为：如果一个婴儿早产并存活，那么合适的称呼应该是早产婴或者早产宝宝，而非胎儿。

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The Omega 3 fatty acids seem to have a positive effect on fetal brain development and may reduce the risk of premature birth. There are positive effects on the growth and health of the fetus.

w - 3脂肪酸对于胎儿大脑的发育有积极的作用，并可能减少早产的风险，还有利于胎儿的发育和健康。

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However, if the mother ill, probably through the placenta vertical mode of transmission of infection fetus, and is likely to result in premature and low birth weight lower.

但如母亲患病，可能通过胎盘母婴垂直传播方式感染胎儿，并有可能导致早产及婴儿出生体重降低。

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