WASHINGTON Senate Democrats want to postpone confirmation hearings for Rep. Tom Price (R-Ga.), President-elect Donald Trumps nominee to head the Department of Health and Human Services, until investigations of his stock trading end.

Sens. Elizabeth Warren (D-Mass.), Tammy Baldwin (D-Wis.) and Al Franken (D-Minn.) on Tuesday called for postponement of the hearings, and sent a letter to Price asking for details of his purchase of an Australian biotech stock.

Democratic Senate Leader Chuck Schumer (D-N.Y.), meanwhile, took to the floor of the Senate to call for a delay, citing his request that the Office of Congressional Ethics investigate Prices investments. Sen. Kirsten Gillibrand (D-N.Y.), author of the 2012 STOCK Act that bars insider trading by members of Congress, also asked the Securities and Exchange Commission to investigate.

A Senate committee has scheduled a confirmation hearing for Price on Wednesday amid a barrage of news stories raising questions about his stock trading while in office.

Kaiser Health News reported on Friday that Price received shares of an Australian biotechnology firm at a discounted rate not available on the open market. CNN reported on Monday that Price invested in a medical device manufacturer prior to introducing legislation specifically tailored to help that company. On Tuesday, Time reported that Price had purchased shares in six health care companies in 2016 while introducing legislation those companies lobbied to enact. The Wall Street Journal reported last month that Price had traded around $300,000 in shares of health care companies while working on legislation that would directly affect their bottom lines.

Price has claimed that his stock trades were made from a broker-directed fund operated by Morgan Stanley. All trades were made by his financial adviser, according to a fact sheet put out by the Trump presidential transition team. A spokesman for Morgan Stanley said the bank does not comment on private client accounts.

The Trump fact sheet was released in response to the CNN report that Price introduced legislation to help medical-device maker Zimmer Biomet soon after purchasing stock in the company. The statement said Prices financial adviser purchased $2,698 in Zimmer Biomet on March 17, 2016. Price reportedly did not learn about the purchase until April 4, 2016 12 days after he introduced legislation to delay a Medicare payment model for a specific medical device manufactured by Zimmer Biomet. Price had made $296 on the trade as of Jan. 13, according to the statement.

Price reached an agreement with the Office of Government Ethics to divest his stock holdings upon his confirmation as HHS secretary.

Ethics experts told HuffPost that they endorse an investigation into Prices trades because there arent enough public facts to know whether he violated the STOCK Act or House ethics rules regarding conflicts of interest and the acceptance of improper gifts.

I have no idea whether Rep. Price had any insider information, Common Causes Paul S. Ryan, a campaign finance and ethics lawyer, said, referring to the Zimmer Biomet trade.