Officers arrested the two Bulgarian nationals in Neunkirchen, in the state of Saarland, on Thursday, police said in a statement.
The 58 year-old-man and his 51-year-old wife are accused of being part of a criminal organization that trades in newborn babies. Both are in custody, police said.
The case originated in Bulgaria, where authorities had issued a European Arrest Warrant for the couple.
The two are thought to have brought at least eight heavily pregnant women from Bulgaria to neighboring Greece.
Once the babies were delivered in Greece, the two suspects allegedly handed the newborns to other members of their criminal gang for resale, the police allege. The mothers in turn were promised payment.
After extensive investigations, Saarland police authorities took in the couple while the two were driving a car. The two have appeared at the Saarbruecken district court and are now being held in two correctional facilities, in Saarbruecken and Zweibruecken, respectively.