(S (S (NP (BASENP (NNS Doctors)) (VP (VP (VBG performing) (BASENP (DT a) (NNP Caesarian) (NN delivery))) (PP (IN in) (NP (DT a) (NP (BASENP (NNP Darwin) (COMMA ,) (NNP Australia)) (NN hospital)))))) (VP (VBD were) (VP (VBN stunned) (S (VP (TO to) (VP (VB discover) (BASENP (DT a) (JJ rare) (JJ ovarian) (JJ ectopic) (NN pregnancy)))))))) (PERIOD .))