( ( ( The symptoms ) ( of menopause ) ) ( ( are ( caused ( by ( changes ( in ( estrogen ( and ( progesterone levels ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NNS symptoms)) (PP (IN of) (NP (NN menopause)))) (VP (VBP are) (VP (VBN caused) (PP (IN by) (NP (NP (NNS changes)) (PP (IN in) (NP (NN estrogen) (CC and) (NN progesterone) (NNS levels))))))) (. .)))
The symptoms of menopause are caused by changes in estrogen and progesterone levels.
(ROOT (S (NP (NNP Estrogen)) (VP (VBZ causes) (NP (NP (DT the) (NNS changes)) (PP (IN of) (NP (NN puberty))))) (. .)))