The reality TV star and her rapper husband have been keen to add another child to their family, which already includes daughter North, four, and son Saint, who was born in December 2015.
Kim was warned by doctors following her last birth that another pregnancy could be life-threatening for her as she suffers from placenta accreta, where the placenta remains attached inside the uterus after birth when it should come out naturally.
Throughout the most recent season of reality show Keeping Up with the Kardashians, she considered her alternatives, and it now seems like they have found a surrogate for their baby.
According to a report from TMZ.com, the couple found the surrogate through an agency and have made a deal, agreeing to pay a total of $45,000 (£35,000) in 10 instalments of $4,500 (£3,600) each month. If there are multiple babies, the surrogate will receive an extra $5,000 (£4,000) for each additional child, and if she loses reproductive organs, she gets an extra $4,000 (£3,000).
As part of the deal, the surrogate must not smoke, drink alcohol or do drugs, go in hot tubs or saunas, handle cat litter, eat raw fish, apply hair dye, or drink more than one caffeinated drink each day for the duration of the pregnancy. She has also agreed to forgo sexual activity for three weeks after embryo implantation.
According to the site, the agreement provides that Kim and Kanye, who paid a deposit of almost $69,000 (£55,000) to the agency, "assume the legal and parental responsibilities for any child."
During the reality show, Kim's mum Kris Jenner offered to serve as her surrogate and her sister Khloe visited a doctor to see if she was a viable candidate, but the appointment made her realise she wanted her own family instead.
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