They believe the woman has "critical knowledge" of the case.
Maryland State Police released screenshots of the woman, taken from a video recorded in 2020.
The images show an adult woman with "distinctive tattoos," police said. She has a chest tattoo with multiple arm and wrist tattoos. One wrist tattoo appears to read "Dugo" or "Drigo" and has the numbers 12-17-16, police said.
"Investigators believe this woman has specific knowledge related to the identity of a female infant that was sexually abused," police said in a news release.
The child victim is now believed to be 4 to 5 years old.
Further details were not released due to the nature of the case and to protect the integrity of the investigation, Maryland State Police said.
Anyone with information is asked to contact the Maryland Internet Crimes Against Children Task Force at 443-486-3335. Anonymous callers can contact Metro Crime-Stoppers Maryland at 1-866-756-2587.
All callers should reference case #22-MSP-043527.