Khloe Kardashian has chosen Tristan Thompson as her sperm donor.

The 35-year-old reality TV star is freezing embryos in order to potentially have a second baby, and the basketball star - with whom she has two-year-old daughter True - will be assisting in the process, despite her having reservations about his involvement.

During the latest episode of 'Keeping Up With the Kardashians', Khloe shared: ''I might be able to freeze 25 eggs, but that doesn't mean any of them will end up healthy.

''The only way of having the knowledge that you have a strong embryo is if you mix egg and sperm together - and if you're going to go through this process, you want to go through it with the best guarantee that it's going to be a success at the end of the day.

''What if you're 40 and you want to thaw your eggs and create embryos and they tell you, 'Ah! Well, all your eggs are bad!' It's like a tug of war and I don't really know what to do.''

Khloe discussed the issue - and the identity of her donor - with her sisters Kourtney Kardashian and Kendall Jenner.

She said: ''I've been doing hormone injections for about five days and the injection process has been fine. I don't know why, I'm like, 'Oh, OK, it's not that bad.'

''I do have a sperm donor. Yeah, Tristan.''

However, the TV star admitted the scenario was ''weird'' as she and Tristan are no longer together.

Speaking to her sisters, she explained: ''He has to sign, like, legal paperwork that he would just be my sperm donor.

''But you never know. What if, in three years, I get married to someone and I'm like, 'You know what, I don't want that.'''

The 29-year-old sportsman - who split from Khloe after he kissed model Jordyn Woods - pledged to support his ex-girlfriend through the process.

He told her: ''I'm open to doing that and down for doing that.

''At the end of the day, I want whatever is gonna make you feel comfortable and also makes you feel safest and everything, that's what I'm on board with ... so however I can help.

''When I come out in the summertime I can do it and we can go from there.''

Khloe also hinted they could rekindle their romance in the future.

She said: ''I have no idea what the future holds for Tristan and I, but I really think I'll feel a lot better knowing I have five embryos in a freezer somewhere.''