Bitcoin slid by almost 6% on Wednesday, having posted its worst monthly performance in April since late 2022, as investors pulled money out of cryptocurrencies ahead of an interest rate decision by the Federal Reserve later.

The value of the world's most traded cryptocurrency fell by nearly 16% in April, as investors booked profits on a sizzling rally that has taken the price to record highs above $70,000.

Bitcoin fell by as much as 5.6% to its lowest since late February. It was last down 4.8% at $57,001, while losses in ether were more modest, down 3.6% at $2,857, also at its weakest since February.

The price of bitcoin is now a full 22% below March's record of $73,803, technically putting it in a bear market. But it is still up 35% so far this year and double where it was this time last year, thanks in large part to the billions of dollars flowing into newly minted exchange-traded funds since January.

"The recent downtrend can be attributed to increased profit-taking by investors who entered the market during the downturns of 2022 and 2023, as well as ETF investors who witnessed significant price appreciation on their shares after entering the market in the early weeks of 2024," Fineqia research analyst Matteo Greco said.

Crypto-related stocks fell in U.S. premarket trading. Shares in crypto exchange Coinbase fell 4.6%, while those in miners Riot and Marathon Digital dropped 4.2-4.3%.

On the macro front, the Federal Open Market Committee (FOMC) is not expected to make any changes to interest rates, but the view is taking root among investors that the central bank may not cut rates at all this year, delivering a blow to interest rate-sensitive assets such as cryptocurrencies, emerging market stocks and bonds or even commodities.

Investors have responded accordingly. The 10 largest U.S. spot bitcoin ETFs are facing their biggest weekly outflow since their inception in January.

Outflows are up to $496 million this week, mostly as flows into BlackRock's iShares Bitcoin Trust, the largest in terms of holdings, have slowed, according to LSEG data.

Even smaller alt-coins, which can sometimes benefit from weakness in the two big tokens, have been punished. Data from crypto website Coingecko shows Solana's sol token has lost almost a quarter of its value over the last seven days, as have meme coins dogecoin and shiba inu - both made popular in 2021 in part by Tesla owner Elon Musk.

Bitcoin's so-called "halving event" last month has done little to prop up the price. Since April 20, when halving took place, bitcoin has dropped some 15%. Many investors bought into the market in the run-up to the event, which involves a change to the cryptocurrency's underlying technology designed to cut the rate at which new bitcoins are created.

From a charting perspective, Alex Kuptsikevich, a senior market analyst for the FXPro platform, said the decline in bitcoin is entering a new stage.

Not only is May a month of seasonal weakness for bitcoin, the leg down in the price in the past few weeks brings $55,700 and $51,000-52,000 into focus, he said.

"However, both FOMC announcements later today and monthly jobs data on Friday have enough potential to accelerate or reverse the downtrend," he said.

(Reporting by Amanda Cooper, additional reporting by Samuel Indyk; Editing by Stefano Rebaudo, Ros Russell and Louise Heavens)