Hi, you may want to try to swaddle baby during sleep if you are worrying about sleeping posture. http://www.sidsandkids.org/safe-sleeping/safe-wrapping/
Also, please make sure that the surface of the bed is firm and there are no pillows/blankets/cot bumpers/soft toys around your baby sleeping area to prevent accidental suffocation.
Avoid using baby sleep positioner to position her sleeping postures. https://www.nichd.nih.gov/sts/about/Pages/tummytime.aspx#other
Yu Shan