UnitedHealth Group has replaced Aetna as the nation's largest health insurance provider.

UnitedHealth Group had more than 16.5 million members as of Dec. 31, 2001, and projects that its January 2002 enrollment will exceed 17 million. Meanwhile, Aetna's enrollment fell to 15.6 million in December 2001, which is down from 17.2 million from December 2000.

UnitedHealth Group, of Minnesota, has been experiencing growth in enrollment for the last several consecutive years. According to Roger Krusin, a spokesperson for UnitedHealth Group, "We are not striving to become the largest health insurer, we're growing organically through a consistent approach in health care coverage." Krusin would not speculate whether the company has any acquisitions plans.

Aetna projects its enrollment continued to decline in January. According to Jill Griffiths, a spokesperson for Aetna, the decline in enrollment reflects the company's downsizing strategy. Aetna experienced a net loss of $279.6 million in 2001, compared to a net loss of $127.1 million for 2000. According to Chairman, CEO and President Dr. John W. Rowe, in order to become profitable, the company will continue to downsize and eliminate unprofitable operations. Aetna maintains that the composition of its membership is more important than the size of its membership.

CIGNA Corp. is ranked as the nation's third-largest health insurer with an enrollment of 14.3 million.