US natural and organic retailer Sprouts Farmers Market has forecast comparable-store sales in the first quarter of its financial year will rise by 12.5%.

Sprouts, which operates 170 stores in nine states, made the announcement ahead of its planned publication of its results for the quarter to 30 March.

The disclosure came as investors, including private-equity firm Apollo Global Management, sold more shares in Sprouts, which floated last summer.

The retailer said it expects net sales for the quarter to rise 26% to around US$720m.

Gross margin will be in the range of 30.5-31%, compared to 30.3% for the same period of fiscal 2013, it said.