Gold Fields backed its full-year production and cost guidance despite a drop in first-quarter output.

South Africa’s largest gold miner said Tuesday that it produced 464,000 ounces of gold in the quarter, down from 577,000 ounces in the same quarter a year prior, driving a 51% increase in all-in sustaining cost–or AISC–of $1,738 per ounce.

Attributable gold production fell across most of its operations due to weather-related events and operational challenges, particularly at Gruyere and St. Ives in Australia, South Deep in South Africa and Cerro Corona in Peru.

Following two fatalities during the quarter, the company has initiated an independent review on its safety standards. It is expected to complete during the first half of the year.

Despite the challenges, Gold Fields, one of the largest gold-producers in the world, kept its guidance for full-year production and costs, still targeting an output between 2.33 million and 2.43 million gold-equivalent ounces at an AISC between $1,410 and $1,460 an ounce.