New research out of England backs up what parents have been saying forever: having a baby takes a toll on your sleep.

The study, released Monday, indicates mothers tend to sleep an hour less than normal within the first three months after childbirth, while both parents can expect sleep disruptions up to six years later.

The research group out of the University of Warwick -- in collaboration with the German Institute for Economic Research and West Virginia University -- studied sleep patterns among 4,659 parents who had a child between 2008 and 2015 and also conducted yearly interviews with the subjects about their sleep tendencies.

The researchers also found women can expect to sleep 20 minutes less than normal six years after the birth of their first child, while men had their sleep disrupted by 15 minutes throughout the same time frame.

"While having children is a major source of joy for most parents it is possible that increased demands and responsibilities associated with the role as a parent lead to shorter sleep and decreased sleep quality even up to six years after birth of the first child,” Dr. Sakari Lemola with the University of Warwick’s psychology department, said in a news release.

Researchers also say new parents and parents who breastfeed were among those whose sleep was most significantly impacted by childbirth.