Coventry Health Care Inc. on Tuesday revealed that soaring membership, rates hikes and lower costs have nudged the company's profit by 24% during the fourth quarter, exceeding profit expectations, as overall membership rose while medical costs fell.

In line with the estimates by analysts, health insurer Coventry Health Care reported a 52 percent plunge in its fourth-quarter profit, largely due to an increase in medical costs, which resulted in increase in costs of claims, while it membership fell.