Name the medicine field related to pregnancy that starts with letter W
SELECT DISTINCT ?sbj ?sbj_label WHERE { ?sbj wdt:P31 wd:Q35456 . ?sbj wdt:P3489 wd:Q28123568 . ?sbj rdfs:label ?sbj_label . FILTER(STRSTARTS(lcase(?sbj_label), 'w')) . FILTER (lang(?sbj_label) = 'en') } LIMIT 25 
essential medicine: Q35456 : Q28123568