Research shows that this will prevent embryos from getting oxygen and nutrientsubstance which are necessary for life.This may injury embryos and cause the premature delivery or underweight.

• 研究表明，这会妨碍胎儿获得发育所需要的氧气和营养物质，这可能对胎儿造成伤害，引起早产或胎儿体重不足。