flushleft adds empty page when used for bibliography

Question

I have a small problem in my thesis:

I need the Bibliography to be left-justified and used a simple \begin{flushleft} command to realize that:

\bibliographystyle{unsrtnat} 
\lhead{\emph{Bibliography}}
\begin{flushleft}
\bibliography{Bibliography} 
\end{flushleft}

I realized though, that when adding this flushleft command, that a blank page gets created in front of the Bibliography. Any idea as to why that is happening?

I am using:

\documentclass[a4paper, 11pt, oneside]{Thesis}
\usepackage[square, numbers, comma, sort&compress]{natbib}