Michael Conway was found guilty of 14 charges on June 11 following a trial at the High Court in Livingston.
The 66-year-old targeted his victims in the West Lothian area between the late 1970’s and 2021.
His child victims were aged between four and fourteen when the abuse began.
One woman was repeatedly raped and assaulted, including on occasions when she was asleep and unable to give consent.
Conway also inappropriately touched a second adult female.
The paedophile was convicted of using indecent behaviour towards four girls under the age of 16.
He was found guilty of two further sexual assault charges against two other children.
On August 13, at the High Court in Glasgow, Conway was given an extended 18-year sentence with 14 years in custody.
His name has been added to the sex offenders register indefinitely.
Scotland’s Procurator Fiscal for High Court Sexual Offences, Katrina Parkes, said:
“Michael Conway is an opportunistic abuser who exploited his position of trust to sexually offend against these women and young girls.
“Despite his depraved actions inflicting unimaginable trauma, the victims showed incredibly bravery giving evidence which has ensured he has now been convicted and held accountable.
“We would urge any victim of similar crime not to suffer in silence but to report it, no matter how long ago the offences occurred.
“You will be listened to and supported as we seek to secure justice using all the tools available to us.”