I have tried to get pregnant many times my boyfriend and I found out that you can't get pregnant while standinf up or doing other position except missionary should I try that or what are my other options?

That theory is a load of old rope! Mrs Charming and I simply made love at every opportunity for 3 weeks and she didn't menstruate for 9 months, hope you get lucky soon, keep trying, its fun!

The position has very little to do with it. It could be something to do with your cycle. You need to get the timing right. Most women only ovulate for about 3-5 days out of every month, and you're unlikely to get pregnant unless you have sex on those days.
Do you have a history of using implanted or ingested contraceptives? If so, it might take your body a while to readjust to it's normal functions.
If you keep trying and failing, you and your boyfriend should both see a doctor.
Good luck,
Kal

If you are serious getting having children the both of you need to see a doctor and make sure everything is working right. And position has nothing to do with it. You said boyfriend do you plan on getting married. Are you ready to have a family?

Sexual position doesn't have too much to do with it. Some positions like women on top allows for more semen to leak out, while positions such as missionary allow gravity to help and keep the semen in your body longer, allowing for those little guys to do their job.

The key here is to find out when you are ovulating.