How does sex position impact pregnancy?
While there are no scientific studies regarding the best sexual positions for baby-making, the missionary (man on top) position is typically considered optimal for conception.
It is also suggested to place a pillow under the hips and keep the legs raised after sex which may enhance the sperms' ability to swim upstream.
You can, of course, get pregnant in almost any position, but there are certain anti-gravity positions such as sitting, standing, or woman on top that may discourage sperm from traveling upstream.