Coming off a big year for IPOs in 2014 and a strong economy, many observers expected that the first three months of 2015 would see the momentum for public stock offerings continue.

Nope.

According to the Q1 stats released today by Renaissance Capital, the U.S. IPO market fell to its slowest pace in two years, despite healthy economic fundamentals. Renaissance said the drop-off for tech-related IPOs was likely due to the growing volume of late-stage capital being pumped into companies like Uber, which has spawned a growing number of private companies with valuations over $1 billion.

In other words: Blame the unicorns.

“Technology IPO issuance was likely dampened by the widespread availability of private funding at very high valuations, which produced little urgency for companies to seek IPO capital,” said the report from Renaissance.

According to Renaissance, there were 34 IPOs in the U.S. that raised $5.4 billion in the first quarter. That was down from 64 in the same quarter a year ago, and it was the fewest since the first quarter of 2013.

The amount raised was down from $10.6 billion raised in the same period a year ago, and the smallest amount raised in a quarter since Q3 2011.

And within those diminished numbers, biotech and health care accounted for about half the IPOs. Things get uglier when you just look at tech, where there were only 4 IPOs that raised $1.2 billion in the quarter. That includes Box, which got off to a strong start early in the year.

Still, Renaissance said the few tech companies that went public may not have inspired a ton of confidence.

“Because recent high-profile tech deals like Box, Hortonworks and New Relic came public at valuations below their most recent private financing rounds, some pending VC-backed technology companies may have chosen to delay their IPOs,” the report said.

What’s more, the road ahead is not looking much brighter for IPOs.

“Only 47 companies submitted initial filings in the 1Q 2015, down from 98 in the 1Q 2014,” Renaissance said. “The total IPO pipeline now contains 122 IPOs looking to raise $22 billion, about the same number of deals as one year ago but 33 percent lower in terms of proceeds.”

In the tech sector, Renaissance noted, “There are just five up-to-date technology filers and three consumer deals, indicating the dry spell for these sectors could carry on through April.”