Republican senators have released a series of text messages from Dr Anthony Fauci’s government-issued phone, including a January 2021 discussion about the potential risks of Covid vaccines during pregnancy. Senators Ron Johnson and Rand Paul published the messages on Monday, saying they were taken from Fauci’s phone and involved Fauci, Rochelle Walensky, then director of the Centers for Disease Control and Prevention (CDC), and Vivek Murthy, who was US Surgeon General at the time.

One of the messages shows Fauci expressing concern that the second dose of a Covid vaccine “theoretically could be associated with miscarriage in the 1st trimester” of pregnancy.

The messages date from 25 and 26 January 2021, shortly after Covid vaccines began to be rolled out in the US.

The senators said the phone contains more than 34,000 text messages and 522 voicemails.

“Oddly, only three contacts are listed; all other text messages are identified only with phone numbers rather than contact names,” they said in a statement. “It is too early to determine whether any data has been deleted,” they added.

Johnson has requested transcribed interviews with Fauci and other Food and Drug Administration (FDA) officials as part of his investigation into the government’s response to the pandemic.

He has alleged that senior FDA officials ignored warnings that the agency’s Covid vaccine safety monitoring system was failing to detect potential safety signals.

The newly released messages come after Fauci appeared before the Senate Homeland Security and Governmental Affairs Committee last month.

During that hearing, Fauci invoked the Fifth Amendment 111 times while being questioned by senators. Mr Paul later referred a contempt vote against Fauci to the Department of Justice.

In his opening remarks at the hearing, Fauci accused Paul of having an “unhinged obsession” with him.

The hearing became heated at several points.

Republican Senator Bernie Moreno called Fauci a “total disgrace” and said he had felt compelled to run for office after seeing a mother arrested while watching a football game outside with her family for allegedly violating Covid-related government guidelines.

“Who the f**k do you think you were for doing that? It was a total disgrace to this country,” Moreno said.

Fauci’s lawyer, David Schertler, was also removed from the hearing by security after attempting to speak on his client’s behalf.

“I didn’t invite you here to testify,” Paul told him before ordering guards to remove him.

Democratic Senator Richard Blumenthal later read a statement from Schertler accusing Paul of conducting something other than “a serious effort to seek information”.

The statement said Paul had “built a personal brand” around his pursuit of Fauci.

Paul rejected the criticism, saying that a witness who invokes the Fifth Amendment cannot then have their lawyer testify on their behalf. “The attorney is complaining and testifying, saying you didn’t do it. The prosecution is unfair. You don’t get to do that,” Paul said. “That’s one thing you give up when you take the Fifth Amendment and say I’m not going to testify.”

“He was not invited to testify, he was out of order, and it was appropriate to have him ejected,” Paul later told reporters and attendees.

The latest texts are part of a wider Republican examination of the US government’s handling of the Covid pandemic.

Paul released Fauci’s personal diaries last month, which he said provided an insight into Fauci’s activities and interactions with public figures during the pandemic.