Metropolitan Police officer David Carrick has been charged with three more counts of rape, bringing the total charges against him to 44.
The 47-year-old constable already faced 41 charges involving 11 alleged victims.
His alleged crimes included rape, coercive and controlling behaviour and sexual assault between 2003 and 2020.
On Monday, the Crown Prosecution Service authorised Hertfordshire Constabulary to charge Carrick with the additional offences which relate to one complainant and are alleged to have taken place between 2008 and 2009.
He will appear at Westminster Magistrates’ Court on Friday in relation to the new charges.
The charges include 21 counts of rape, nine counts of sexual assault, five counts of assault by penetration and three counts of coercive and controlling behaviour.
The Met said: "We recognise that these are extremely serious and concerning allegations. Referrals have been made to the Independent Office for Police Conduct as the investigation has progressed.
"The Met’s Directorate of Professional Standards continues to monitor developments closely and will provide whatever support it can to Hertfordshire officers.
"National regulations dictate that any misconduct proceedings must await the outcome of the criminal case."