Portland-based MaineHealth, the state’s largest private employer, is adding paid parental leave to its employee benefits package beginning Oct. 1.

Several of Maine’s largest employers now offer some form of paid leave for mothers and fathers following the birth or adoption of a child, including Hannaford, Walmart, L.L. Bean, Unum, Wex and Idexx.

MaineHealth’s new benefit includes four weeks of leave at full pay and applies to birth mothers, non-birth parents and adoptive parents following the arrival of their new child, the health care group said in a news release.

“MaineHealth is committed to the health of our communities, and that means strengthening families as they grow by creating policies that are flexible and inclusive for our over 19,000 employees,” MaineHealth Chief Human Resources Officer Judy West said in the release. The benefit applies to all eligible full- and part-time employees.

MaineHealth said the new benefit positions it among the nation’s leading health care organizations investing in robust benefits programs to attract and retain a talented workforce.

Scarborough-based Hannaford Supermarkets, Maine’s second-largest employer, announced in August that it was adding a paid parental leave benefit for all employees with at least a year on the job and working at least 30 hours per week.

Walmart, Maine’s third-largest employer, began offering paid parental leave in February 2018 for full-time employees. Freeport-based L.L. Bean, Maine’s fifth-largest employer, implemented a similar policy in January 2018. Like at Hannaford, L.L. Bean’s parental leave policy also applies to all year-round employees working at least 30 hours per week.

Other large employers in the state also have instituted parental leave policies in recent years. Unum Group began offering paid parental leave in February 2018. Wex Inc. of Portland began offering it in 2016, and Idexx Laboratories Inc. in Westbrook implemented a “bonding leave” benefit in 2014, which provides two weeks of fully paid leave to non-birth-mother parents to bond with their newborn or adopted child.

The state’s fourth-largest employer, Bath Iron Works, does not disclose the specifics of its employee benefits policy. Company spokesman David Hench said the reason is that the largely unionized business has “varied accommodations in different contracts that have been negotiated with the different bargaining units.”

Most employers in Maine have faced challenges attracting and retaining employees as a result of the state’s stagnant job creation and an unprecedented period of extremely low unemployment. Maine’s unemployment rate has been below 4 percent for 44 consecutive months, the longest period on record.

According to a 2018 employee absence and disability management survey by New York-based consulting firm Mercer, at least 40 percent of employers nationwide now offer paid parental leave to non-birthing parents, up from 25 percent in 2015.