"Morning sickness" is often taken lightly, but when it becomes severe, it is called "hyperemesis gravidarum" and requires an IV and other forms of medical care.
The concept of "Tatemae" tends to be misunderstood as lying. But I think it's not lying in the sense of deceiving others, but rather as a way of respecting others' differences in opinion without making them uncomfortable. It's a cultural aspect stemming from how Japanese people tend to avoid arguments in favor of keeping the peace.