Objective To explore the distribution characteristics and correlations among the natures

flavors and channel entries of pregnancy contraindicated Chinese herbs. Methods Chinese Materia Medica（ 《中华本草》） and CNKI were searched

and 1136 pregnancy contraindicated Chinese herbs were found. Data on the herbs was analyzed by association rules and correspondence analysis. Results The four natures of pregnancy contraindicated Chinese herbs are most warm

cold and neutral; as for the five flavors

bitter is most

then acrid and sweet; for the channel entries

the liver channel is most

then lung

spleen

stomach

kidney

large intestine and heart. The high-frequency nature and flavor combinations are acrid-warm

bitter-cold

bitter-warm

and bitter-neutral. The high-frequency nature and channel entry combinations are warm-liver

cold-liver

neutral-liver and cold-lung. The high-frequency flavor and channel entry combinations are bitter-liver

acrid-liver

bitter-lung and sweet-liver. Conclusion During pregnancy

more attention should be paid on acrid-warm and bitter-cold Chinese herbs

so as the warm-liver and bitter-liver ones.