Stitch Fix is bracing for a more challenging environment in the new fiscal year, which is projected to temper sales.

The curated clothing company expects revenue in the current first quarter of $323 million to $328 million, which would be a decline of 4.1% to 5.6% year over year. Stitch Fix on Wednesday said it is starting the year with a lower number of active clients.

Stitch Fix said its sales outlook for the quarter was affected by its decision to adjust the timing of some shipments to the fourth quarter. There was also an unintended change made to post-checkout offer flow in August that limited the number of clients eligible to request another order. That issue has been corrected and won't affect results after the first quarter, the company said.

For the year, Stitch Fix is anticipating $1.31 billion to $1.36 billion in annual sales. That would be below Wall Street estimates of $1.40 billion, according to a survey of analysts by FactSet.

The company posted a fourth-quarter net loss of $2.1 million, or 2 cents a share, compared with a loss of $8.6 million, or 7 cents a share, a year earlier.

Revenue in the quarter rose 4.2% to $324.4 million. Analysts surveyed by FactSet forecast revenue of $325.5 million.

The number of active clients decreased 1.4% to 2.28 million. Net revenue per active client increased nearly 8%.

Shares dropped 16% to $2.36 in after-hours trading.