Any baby’s arrival is a cause for a celebration, but when the baby comes too early -- as may have happened in the case of Kim Kardashian’s child -- complications can mar the happy event. (Happily, the Kardashians have reported that Mom and baby are both healthy and doing well.)

Over the weekend, Kardashian delivered her daughter with rapper Kanye West, five weeks ahead of her reported due date. There is some speculation that the reality star may have been somewhat misleading about the due date in order to dodge the paparazzi. But stress and anxiety can be a risk factor for premature delivery, and the reality star has certainly had her fair share of distress in recent months. Her divorce from the basketball player Kris Humphries was finalized in April, after an acrimonious separation following a very publicized marriage. And her partner, West, has been accused of infidelity by a Canadian model who claims to be the other woman. (His rep denied the accusations.)

Doctors define “premature” as any birth that happens after less than 37 weeks of pregnancy (three weeks shorter than the usual gestation period). Early delivery means that a baby has had less time to develop in the womb, so he or she is more vulnerable. According to the Mayo Clinic, a baby born after the usual 40 weeks has a median weight of 7.9 pounds, while a baby born five weeks premature (like Kardashian’s and West’s child may have been) has a median weight of 5.6 pounds.

Premature babies can experience both short-term and long-term complications after arriving into the world. Their immature organs -- heart, lungs, gastrointestinal system, et cetera -- usually don’t function as well as those of a fully-developed baby. This can lead to an array of problems, including trouble breathing, heart defects, low blood pressure, anemia, jaundice and necrotizing enterocolitis (where portions of the infant’s bowel die). Possible long-term complications can include impaired cognition, including a raised risk for learning disabilities, cerebral palsy, vision, hearing and tooth problems, and other chronic health issues. One 2010 study of thousands of middle-aged Danish people found an association between premature birth and type 2 diabetes.

Luckily, many hospitals have facilities to take care of premature babies, and minimize any health risks. Incubators help a baby regulate its body temperature (premature babies lose body heat quicker). Doctors will treat jaundiced premature babies with special lights that help the child break down excess bilirubin (the compound that gives a yellow color to urine, bruises and jaundiced skin). Intravenous tubes can deliver nutrients, fluids and blood, if necessary. Doctors may squirt special liquids into a premature baby’s lungs to help his or her lungs mature, and administer antibiotics to counter possible infections.

Generally, a premature baby is safe to go home with its parents when it can maintain a stable body temperature outside of an incubator, breathe and feed unassisted, and exhibits steady weight gain. Parents of premature babies may have to be more vigilant than most about limiting their child’s exposure to infections. Given the size of the extended Kardashian clan, the new arrival should have plenty of people looking out for her.