(QT (DQL ``) (QTC (S (ADVP (RB However)) (COMMA ,) (S (BASENP (DT no) (JJ previous) (NN study)) (VP (VBZ has) (VP (VBN tested) (SBAR (IN whether) (S (BASENP (NN pregnancy)) (VP (ADVP (RB actually)) (VP (VBZ results) (PP (IN in) (NP (NP (BASENP (DT the) (NN production)) (PP (IN of) (BASENP (JJ new) (NN myelin)))) (COMMA ,) (SBAR (WHNP (WDT which)) (S (VP (MD may) (VP (VB lead) (PP (TO to) (NP (BASENP (NN improvement)) (PP (IN of) (BASENP (NNS symptoms))))))))))))))))))) (PERIOD .)) (DQR ''))