Normall use 2 times per day,one in morning,the other one at night,u can set up any time u want,e.g,morning @9am,night@9pm,u have to follow your specific time once u set up yr own schedule.
I start using it when I reached 18 weeks,and I m almost 32 weeks now,I found that he is more active while I using it,3 of my friends used it before and all of them hv good comments so I just give a try.
If u are worrying about the noise,u can use a clothe(薄果種)to cover yr tummy when u use it.
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