A source tells PEOPLE Kardashian West, 35, suffered from placenta accreta, the same condition she experienced during her first pregnancy with daughter North, now 2.
"She had a really tough birth because of the issues with her placenta," the source says.
Placenta accreta occurs when blood vessels and other parts of the placenta grow too deeply into the uterine wall and remain attached. Though typically a woman's placenta is delivered following the birth of the baby, in the case of North, Kardashian West's placenta did not detach. As result of the high-risk condition, a doctor had to scrape it out by hand.
The reality star opened up about her past pregnancy complications in a post on her website and app last month when discussing her concerns about childbirth the second time around.
Calling the procedure to have the placenta removed following North's birth the "the most painful experience" of her life, the reality star admitted that she was at risk of having placenta accreta again.
"There's not a whole lot I can do to prevent it, so my anxiety is a little high leading up to my delivery," Kardashian West said.
The Keeping Up with the Kardashians star also discussed the condition during an interview for the September issue of C Magazine.
"They think I’ll have placenta accreta again, so if the placenta grows a little bit deeper than it did last time, then they are prepared to have my uterus removed, which is a little scary for me," she told the magazine.
Despite the difficulties, Kardashian West gave birth to her son, who was born weighing 8 pounds and 1 ounce, on Saturday in Los Angeles. On Monday, she and husband Kanye West, 38, revealed they had chosen to name their newborn Saint.