###HUMAN: what are the four most frequent specimen tests that patients had within the same month after having been diagnosed with 29-30 comp wks gestation until 2104?, ###ASSISTANT: SELECT t3.spec_type_desc FROM (SELECT t2.spec_type_desc, DENSE_RANK() OVER (ORDER BY COUNT(*) DESC) AS c1 FROM (SELECT admissions.subject_id, diagnoses_icd.charttime FROM diagnoses_icd JOIN admissions ON diagnoses_icd.hadm_id = admissions.hadm_id WHERE diagnoses_icd.icd9_code = (SELECT d_icd_diagnoses.icd9_code FROM d_icd_diagnoses WHERE d_icd_diagnoses.short_title = '29-30 comp wks gestation') AND STRFTIME('%y', diagnoses_icd.charttime) <= '2104') AS t1 JOIN (SELECT admissions.subject_id, microbiologyevents.spec_type_desc, microbiologyevents.charttime FROM microbiologyevents JOIN admissions ON microbiologyevents.hadm_id = admissions.hadm_id WHERE STRFTIME('%y', microbiologyevents.charttime) <= '2104') AS t2 ON t1.subject_id = t2.subject_id WHERE t1.charttime < t2.charttime AND DATETIME(t1.charttime, 'start of month') = DATETIME(t2.charttime, 'start of month') GROUP BY t2.spec_type_desc) AS t3 WHERE t3.c1 <= 4