how many times should i ejaculate to get her pregnant (in one night)?

It really doesn't work like that. If you ejaculate in her right before ovulation, she has a 20% chance of getting pregnant. If you ejaculate in her twice right before ovulation, she has a 20% chance of getting pregnant. If you ejaculate in her three times right before ovulation, she has a 20% chance of getting pregnant. If you ejaculate in her four times right before ovulation, she has a 20% chance of getting pregnant.

Need I go on?

it only takes one time cause there is thousands of sperm... however if the problem is that you are having trouble getting ehr pregnet then there can be reasons... like some woman cannot conceive witch means they caonnot have kids or will have a very hard time getting pregnet.. and some guys dont have a big enoiugh sperm count or even abnormally shaped sperm cannot fertilize an egg.

but a good tip that works really well is after u ejaculate in her have her lay upside down for a few min... it really wokrs

What matters is how strong your sperm is not how many times you come..thats why girls get pregnant on their first time ever to have sex because the guys sperm must of been strong

It only takes once but as many as you can will increase your chances.

What matters the most is if she is ovulateing try after her period

you really only have to once.