Analysis and sorting of motile cells

A method for analyzing sperm, comprising:

• introducing a population of sperm into an inlet port at a first end of a microfluidic channel;
• incubating the population of the sperm in the microfluidic channel without an externally driven fluid flow to allow at least a first portion of the population of sperm to move through the microfluidic channel to an outlet port at a second end of the microfluidic channel, thereby separating the first portion of the population of sperm at the outlet port from a second portion of the population of sperm at the inlet port or within the microfluidic channel;
• acquiring a plurality of images of at least the first portion of the population of sperm within the microfluidic channel while the first portion of the population of sperm moves through the microfluidic channel;
• and
• determining a characteristic of at least the first portion of the population of sperm based on the plurality of images.

A device for sorting motile cells, comprising:

• a microfluidic channel, the height of the microfluidic channel selected to be less than 50 μm;
• an inlet port connected to a first end of the microfluidic channel and configured to receive a population of sperm;
• an outlet port connected to a second end of the microfluidic channel,
• wherein the microfluidic channel is configured to provide a first portion of the population of sperm at the outlet port without an externally driven fluid flow in the microfluidic channel and to provide a second portion of the population of sperm within the microfluidic channel or at the inlet port, the first portion of the population of sperm having an average motility higher than an average motility of the second portion of the population of sperm.