You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Queen_Victoria

Context:
In 1853, Victoria gave birth to her eighth child, Leopold, with the aid of the new anaesthetic, chloroform. Victoria was so impressed by the relief it gave from the pain of childbirth that she used it again in 1857 at the birth of her ninth and final child, Beatrice, despite opposition from members of the clergy, who considered it against biblical teaching, and members of the medical profession, who thought it dangerous. Victoria may have suffered from post-natal depression after many of her pregnancies. Letters from Albert to Victoria intermittently complain of her loss of self-control. For example, about a month after Leopold's birth Albert complained in a letter to Victoria about her "continuance of hysterics" over a "miserable trifle".

Question:
Hysteria and loss of control after the birts of many of her children were likely caused by what?

post-natal depression