According to Wikipedia Sources, Devi Bhagavata Purana mentions Mandodari was Sita's Mother, as well the same is mentioned in Abhuta Ramayana, If So, Where is the Respective Mentions for the Same.
Note: The story about the origin of Sîtâ Devî runs thus :-- Râvana, the king of Ceylon (Lankâ) practised very severe austerities and got extraordinary powers. He brought the three worlds under his subjection, levied taxes from all. The Devas and all the other inhabitants of the several worlds paid their taxes, as imposed by Râvana. Râvana sent messengers to the Risis and the Munis, the ascetics, dwelling in forests and asked them to pay their taxes. The Risis replied that they had no property. But Râvana insisted. The Risis gave, then, blood, cutting their thighs, in a jar that was carried to Lankâ. Râvana kept that jar under the custody of his queen Mandodarî, and instructed her that the jar contained poison and that she should not eat that. Mandodarî, however, ate a portion of that, out of curiosity, and became pregnant and gave birth to a daughter. Fearing Râvana, she floated the jar with the daughter, in the ocean, which, floating through oceans and rivers, came and touched the lands of the King Janaka. The peasants while tilling, found that and took the girl to the king, who reared her as his daughter. Thus Sîtâ, born out of the blood of the Brâhmanas, took away subsequently the kingdom, life, and all of Râvana.
Another version is this :-- As before, the messengers advised the Munis to give something; otherwise Râvana would insist and put them to various troubles. So the Munis cut their thighs and gave blood as their tax, saying that that blood in the jar would cause ruin and desolation to the country where it will be kept. Râvana, hearing this, ordered the jar to be carried to the kingdom of the king Janaka, thus causing ruin to him. The jar was brought and placed in the fields of Janaka. Now it happened that there was a very severe drought; rains were absolutely wanting; and a dire famine was imminent. The Brâhmin Pundits informed the king that if the king and his wife ploughed themselves the fields, rains would fall. So the king with his wife did that, the king holding the plough and the queen holding the hand of the king. The fore end of the plough accidentally hit upon that jar, out of which came out Sîtâ Devî with two women Riddhi and Siddhi, waving chowries on her two sides. The two ladies disappeared and Sîtâ Devî looked like a girl. The king Janaka reared her, as if his daughter. Sîtâ Devî used to lift daily with her left hand the bow of S’iva, kept in the king’s house, and daily worshipped that, and thus cleansed the place. Seeing this, the king Janaka pledged the vow that, whoever would break the S’iva’s bow, would marry Sîtâ.
Both these above accounts of Sri Sita's origin are given by the translator as notes on Devi Bhagavatam's 3rd Book's 28th Chapter.
So, as per both these stories, Ravana was somehow involved in the process but he was in neither cases the father. In both the versions it was the blood of the Munis, that Ravana brought, which was responsible for the birth of Sita.
As per the 1st version however, Mandodari, Ravana's wife, actually gave birth to Sita from her womb.
Now, coming to the question whether the aforementioned Purana itself contains these stories or not then it seems - No - because otherwise it wouldn't have been necessary for the translator to give them separately as footnotes under a chapter of that same Purana.