By Anna Hirtenstein

U.S. stocks edged down Monday, suggesting major indexes may retreat after notching records at the end of last week.

The S&P 500 slipped 0.2% in early New York trading. The Dow Jones Industrial Average ticked down 0.2%, and the Nasdaq Composite Index retreated 0.5%.

Investors started the week on a cautious note amid concerns that the rollout of Covid-19 vaccines was facing hiccups. A string of blue-chip companies are scheduled to report earnings this week, and will offer a view on businesses' expectations for the pace of economic revival. Money managers are looking to gauge whether stocks' high valuations are justified after the Dow and S&P 500 hit closing records last week.

"After a big move, you get a pause of breath and a bit of a reassessment, " said Caroline Simmons, U.K. chief investment officer at UBS Asset Management. "People are reassessing, waiting for newsflow that might indicate that growth and inflation remain on track."

U.S. health authorities decided to recommend pausing the use of the Johnson & Johnson vaccine due to concerns about improper treatment of blood clots, The Wall Street Journal reported over the weekend. Health officials are now looking at limiting the J&J vaccine to older people, among other options, and could make public a decision as early as this week.

On the earnings front, International Business Machines is expected to report after the close. Other giant companies including Procter & Gamble are scheduled to post results later in the week.

"I expect the earnings picture is going to remain very buoyant across the picture and for the momentum to stay very positive," said Fahad Kamal, chief investment officer of Kleinwort Hambros. "As long as earnings meet what are very heightened expectations, the rally can keep going."

In bond markets, the 10-year Treasury yield ticked up to 1.587%, from 1.571% on Friday. Yields rise when bond prices fall.

Ahead of the market open, Peloton fell 6% after a federal safety agency said over the weekend that people with young children or pets shouldn't use the connected-fitness company's treadmills.

Tesla declined over 2%, after two men died in a Tesla vehicle that crashed into a tree Saturday. GameStop rose more than 9% after it announced its CEO would step down.

In currency markets, the Russian ruble weakened 0.6% against the dollar. U.S. officials warned there would be consequences if opposition politician Alexei Navalny dies in prison. Calls for mass protests in cities across Russia also mounted. The ruble has lost nearly 3% of its value this year.

Bitcoin edged up over 4% to about $57,000, regaining some ground after plunging almost 12% over the weekend, according to data from CoinDesk. Turkey's central bank said Friday it would ban the use of cryptocurrencies as a form of payment.

"The [cryptocurrency market] is really on edge right now," said Joel Kruger, a currency strategist at LMAX. "There were concerns over the weekend after Turkey came out with the news of major regulatory restrictions coming into force."

Some traders were speculating that the U.S. Treasury could make a similar decision, he said.

Overseas, the pan-continental Stoxx Europe 600 edged up 0.1%, on track to notch a record closing high for the third consecutive trading session.

In Asia, most major benchmarks ticked up by the end of the day. The Shanghai Composite Index climbed 1.5% for its best day in over three weeks. Hong Kong's Hang Seng added 0.5%. However, India's benchmark stock index fell 1.8% as Covid-19 cases continued to climb.

Write to Anna Hirtenstein at anna.hirtenstein@wsj.com

(END) Dow Jones Newswires

April 19, 2021 09:46 ET (13:46 GMT)

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