* ADP report shows 156,000 jobs added in April vs. est. 196,000
* Priceline falls after forecast misses expectations
* Indexes down: Dow 0.6 pct, S&P 0.6 pct, Nasdaq 0.8 pct (Updates to close)
By Caroline Valetkevitch
May 4 (Reuters) - U.S. stocks declined for a second day on Wednesday, weighed down by tepid data on private sector U.S. jobs and a retreat in biotech shares.
Weaker-than-expected results from Priceline added to the weaker tone.
The Nasdaq Biotech Index dropped 2.9 percent, its seventh session of losses out of the last eight.
The ADP private sector employment report showed hiring in April fell to its lowest levels in three years. The report acts as a precursor to the more comprehensive government nonfarm payrolls data, which is expected on Friday.
A strengthening labor market is expected to influence the pace of future rate hikes, although traders are pricing in only one hike later this year.
An accommodative Fed, along with a recovery in oil prices, have helped U.S. stocks rally back from sharp losses at the start of the year. The S&P 500 is up 0.3 percent since Dec. 31.
"The market is absorbing the move from the February bottom. That would make sense to me at this point, given the seasonality and that the market came close to its all-time high. I'm seeing a lot of comments on 'sell in May and go away,'" said Bruce Zaro, chief technical strategist, Bolton Global Asset Management in Boston.
'Sell in May and go away' is a Wall Street adage that refers to stocks being less likely to make big gains in the summer months.
The Dow Jones industrial average was down 99.65 points, or 0.56 percent, to 17,651.26, the S&P 500 had lost 12.25 points, or 0.59 percent, to 2,051.12 and the Nasdaq Composite had dropped 37.59 points, or 0.79 percent, to 4,725.64.
Shares of Priceline fell 7.5 percent to $1,253.04 and was among the biggest drags on the S&P and the Nasdaq. The online travel services company's forecast fell short of expectations.
After the bell, shares of Tesla rose 6 percent following its results. Whole Foods Market Inc rose 3.8 percent after better-than-expected quarterly profit.
Other economic data on Wednesday showed the U.S. services sector expanded in April as new orders and employment accelerated, helping assuage some of those fears.
For the jobs report Friday, a Reuters survey of economists showed nonfarm payrolls likely rose by 202,000 jobs in April after rising 215,000 in March. The unemployment rate is forecast holding at 5 percent.
About 7.7 billion shares changed hands on U.S. exchanges, above the 7.2 billion daily average for the past 20 trading days, according to Thomson Reuters data.
Declining issues outnumbered advancing ones on the NYSE by 1,812 to 1,196, for a 1.52-to-1 ratio on the downside; on the Nasdaq, 1,882 issues fell and 928 advanced for a 2.03-to-1 ratio favoring decliners.
The S&P 500 posted 18 new 52-week highs and 6 new lows; the Nasdaq recorded 30 new highs and 64 new lows. (Additional reporting by Tanya Agrawal; Editing by Nick Zieminski)