Announcing a boost up to $59.9 billion in its full-year revenue forecast in comparison to its previous estimate of $59.5 billion, WellPoint Inc.'s (WLP) announced a 5.7% rise in its first-quarter earnings with better margins and increased investment gains.

Firm’s Chairwoman and Chief Executive, Angela Braly stated, “We are pleased with our positive start to 2011. Our membership and earnings results are higher than we originally anticipated and we are continuing to become a more efficient and effective company”.

Bringing a change in its outlook on WellPoint, Standard & Poor believes that the firm has benefited from lower-than-expected use of medical services by members in the last year and its business is much stronger in comparison to its rivals.

Sources suggest that in the wake of a recent forecast of $1.87 a share on $14.57 billion in operating revenue, the operating revenue declined 1.3% to $14.65 billion, while total revenue declined 1.2% to $14.89 billion.

The rise in full-year earnings outlook by the largest U. S. health insurer was followed by an increase in the forecast by the rivals UnitedHealth Group Inc. and Humana Inc.