Officials arrested the two Bulgarian nationals on Thursday in Neunkirchen in Saarland, the 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 deals in newborn babies. Both are now in custody, said the police.
The case originated in Bulgaria, where the authorities had issued a European arrest warrant against the couple.
The two are said to have brought at least eight heavily pregnant women from Bulgaria to neighboring Greece.
After the babies were delivered in Greece, the two suspects allegedly gave the newborns to other members of their criminal gang for resale, police claim. The mothers, in turn, were promised payment.
After extensive investigations, the Saarland police authorities took the couple in while they were driving a car. The two appeared at the Saarbrücken District Court and are currently being held in two penal institutions in Saarbrücken and Zweibrücken.