Khloe Kardashian is reportedly having fertility treatment.
The 27-year-old socialite - who has been married to basketball player Lamar Odom for two years - is said to have started preparing for in-vitro fertilisation (IVF) treatment in September after having difficulty getting pregnant.
It is believed the couple have had several consultations and Khloe is currently taking pre-natal vitamins, though they have not yet started IVF.
A source told Us Weekly magazine: "They have been trying everything to get pregnant but nothing works.
"She is desperate for a baby with Lamar and will do whatever it takes. They have faith the IVF will work."
Khloe is said to have made the decision to get medical help after her sister Kourtney - who already has a 23-month-old son Mason with her boyfriend Scott Disick - announced she is pregnant again.
The source added: "She's thrilled for Kourtney, but she's really sensitive. And it's hard to see your sister get something you want so badly."
The 'Keeping Up with the Kardashians' star has previously admitted she feels under pressure to have a baby.
Earlier this year, she said: "People keep saying, 'Why aren't you pregnant yet?' That's what scares me, when people are like, 'Did you go to the doctor? Do you know if everything's working?' It's nerve-racking. Sometimes I feel like I'm letting everyone down."
Lamar already has two children, Destiny, 13, and 10-year-old Lamar Jr., from a previous relationship.