By Tony Aiello

NEW HAVEN, Conn. (CBSNewYork) — A Connecticut nurse admits she swapped out anesthesia drugs for salt water, causing excruciating pain to women during infertility treatments.

It happened at a top-rated center affiliated with Yale University.

On Tuesday, one of the victims shared her story with CBS2’s Tony Aiello.

The incident happened in mid 2020 at the Yale Fertility Center in New Haven.

A patient, herself a physician, suddenly realized the anesthesia was not working as she underwent a painful egg harvesting procedure.

“It made me scream. I remember screaming in the middle of the procedure from pain. So I couldn’t … I couldn’t tolerate it,” she said.

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Months later, a letter came from federal investigators explaining how nurse Donna Monticone used a syringe to remove the potent opioid painkiller fentanyl from vials and replace it with salt water, so she could use the fentanyl, herself.

Federal prosecutors say at least 175 vials were tampered with at the facility in New Haven, and at a second site in nearby Orange.

Attorney Josh Koskoff represents four women who suffered incredible pain during IVF procedures.

“They feel betrayed, I think, is an appropriate word to convey their feelings,” Koskoff said.

Koskoff and his client said when the women told Yale Fertility staff about the pain, nothing was done.

“Our concerns, we felt, were dismissed by the providers,” the victim said.

“How is it that after the first complaint of pain they didn’t do a thorough investigation? How was this allowed to go on for as long as it apparently did?” Koskoff added.

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In a statement, Yale said the Fertility Center is, “changing procedures, recordkeeping, and (drug) storage,” so this opioid painkiller swapping can’t happen again.

“I think our health care system needs to learn from this case and implement stronger measures to prevent diversion of addictive substances,” the victim said.

The victim told Aiello she still has nightmares about the pain. It also been a nightmare for nurse Monticone, who faces up to five years in prison. The 49-year-old mother of three has surrendered her nursing license, and gone through rehab.

Prosecutors say the nurse swapped out the drugs over a period of four months. She will be sentenced in May.

Tony Aiello