US insurer MetLife Inc topped estimates for quarterly profit on Wednesday, as premiums and net investment income rose. Life insurers make money by investing coverage premiums into stocks and bonds, hoping to earn more than what they pay out in claims. The company's net investment income rose 34.1% to $4.64 billion, driven by favourable changes in the fair value of securities.

Premiums and fees rose 24% to $13.76 billion in the quarter. MetLife's Asia unit's adjusted earnings grew 21.3% to $341 million, buoyed by volume growth and higher investment margins, while those at its EMEA business grew 20%.

Adjusted earnings at its Latin America business grew 17.5% to $161 million, partially driven by higher sales in Brazil and Mexico.However, MetLife reported a 1.5% fall in adjusted profit in its domestic business, hurt by weakness in its retirement, and property and casualty segments.

The company reported derivative losses of $1.47 billion for the quarter, compared with gains of $939 million, a year earlier. Excluding items, MetLife's profit rose to $1.83 billion, in the fourth quarter ended Dec. 31, from $1.34 billion, a year earlier.