(S (S (S (BASENP (JJ Previous) (NNS studies)) (VP (VBP have) (VP (VBN shown) (SBAR (IN that) (S (BASENP (JJ other) (NNS hormones)) (VP (MD could) (VP (VB reduce) (BASENP (NN myelin) (NN damage))))))))) (CONJP (COMMA ,) (CC but)) (S (BASENP (DT this)) (VP (VBZ is) (NP (BASENP (DT the) (JJ first) (NN study)) (SBAR (S (VP (TO to) (VP (VP (VB show) (NP (BASENP (DT a) (NN mechanism)) (S (VP (TO to) (VP (VB reverse) (BASENP (NN myelin) (NN damage))))))) (CONJP (COMMA ,) (CC and)) (VP (VB establish) (NP (BASENP (DT an) (JJ empirical) (NN connection)) (PP (IN between) (NP (BASENP (DT that) (NN mechanism)) (CC and) (BASENP (NN pregnancy)))))))))))))) (PERIOD .))