Some believe that having the girl on top - or having sex standing up - will prevent pregnancy. Unfortunately for them, sperm don't care about gravity. They have their own means of locomotion.
Tests have been done that show the actual position of the two people during sex - standing up, girl on top, etc - has little to no impact on how many sperm get into the girl and stay in there. The sperm's liquid is very thick and meant to stay inside the girl. The sperm, shaped like tadpoles, are very strong swimmers and are actively trying to get into the uterus to get to the egg.
They simply don't care if that means swimming up or down or sideways. They know how to swim and are very good at it.
If you don't want to get pregnant - use contraceptives! If you do want to get pregnant, use whatever position you enjoy best, and have fun with it! The less stress you are under, the easier it will be.
Lisa's Conception Information and Tips
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