(S (S (S (BASENP (DT An) (JJ ectopic) (NN pregnancy)) (VP (VBZ occurs))) (SBAR (WHADVP (WRB when)) (S (BASENP (DT a) (JJ fertilised) (NN egg)) (VP (VP (VBZ implants) (PP (IN in) (NP (BASENP (DT a) (NN woman) (POS 's)) (NN body)))) (PP (IN in) (NP (BASENP (DT a) (NN location)) (ADJP (JJ other) (PP (IN than) (BASENP (DT the) (NN uterus)))))))))) (PERIOD .))