( ( ( Approximately one-third ) ( of ( the ( susceptible mothers ) ) ) ) ( ( were ( vaccinated ( during ( ( the ( highest ( risk period ) ) ) ( for ( ( viremia ( and ( fetal defects ) ) ) ( -LRB- ( ( ( 1 week ) ( before ( to ( ( 4 weeks ) ( after conception ) ) ) ) ) -RRB- ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (QP (RB Approximately) (NN one-third))) (PP (IN of) (NP (DT the) (ADJP (JJ susceptible)) (NNS mothers)))) (VP (VBD were) (VP (VBN vaccinated) (PP (IN during) (NP (NP (DT the) (JJS highest) (NN risk) (NN period)) (PP (IN for) (NP (NP (NN viremia) (CC and) (JJ fetal) (NNS defects)) (PRN (-LRB- -LRB-) (NP (NP (CD 1) (NN week)) (PP (IN before) (PP (TO to) (NP (NP (CD 4) (NNS weeks)) (PP (IN after) (NP (NN conception))))))) (-RRB- -RRB-)))))))) (. .)))
Approximately one-third of the susceptible mothers were vaccinated during the highest risk period for viremia and fetal defects (1 week before to 4 weeks after conception).
(ROOT (S (NP (DT The) (JJ fetal) (NN period)) (VP (VBZ lasts) (NP (NP (QP (RB approximately) (CD 30)) (NNS weeks)) (NP (NNS weeks)))) (. .)))