Two-thirds of women who had their first child between 2001 and 2003 worked during their pregnancy compared with just 44 percent who gave birth for the first time between 1961 and 1965, according to a report released yesterday by the U.S. Census Bureau.

The report, Maternity Leave and Employment Patterns: 1961–2003, analyzes trends in women's work experience before their first child, identifies their maternity leave arrangements before and after the birth and examines how rapidly they returned to work.

Women are more likely to work while pregnant than they were in the 1960s, and they are working later into their pregnancies. Eighty percent who worked while pregnant from 2001 to 2003 worked one month or less before their child's birth compared with 35 percent who did so in 1961-1965.

Women are also returning to work more rapidly after having their first child. In the early 1960s, 14 percent of all mothers with newborns were working six months later, increasing to 17 percent within a year. By 2000-2002, the corresponding percentages had risen to 55 percent and 64 percent. (The period of analysis is restricted to women who gave birth by 2002 because some who gave birth in 2003 did not have one full year of employment data by the time of the interview in 2004.)

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