A retrospective cohort study using a national surveillance questionnaire to investigate the characteristics of maternal venous thromboembolism in Japan in 2018

Table 1 Recommendations for thromboprophylaxis in Japan

Antepartum thromboprophylaxis
	Group	Risk of incidence	State during pregnancy	Thromboprophylaxis (heparin administration)	Level of recommendation
1)	1	High	Standard	Perform	B
2)	2	Moderate	Standard	Consider	B
3)	2	Moderate	Operation	Perform	B
4)	3	Low	Standard	Consider	C
Postpartum thromboprophylaxis in Japan
	Group	Risk of incidence	I. Thromboprophylaxis (heparin administration) II. Intermittent pneumatic compressions		Level of recommendation
1)	1	High	Perform I or I + II		B
2)	2	Moderate	Perform I or II		B
3)	3	Low	Consider I or II		C

Level A and B treatment are regarded as current standard care practices in Japan. Level A recommendations are stronger than level B recommendations. Informed consent is therefore required when maternity service providers do not provide care corresponding to level A or B recommendations
Level C treatment consists of possible options that may favorably affect the outcome but for which it is unclear whether the possible benefits outweigh the possible risks. Thus, care corresponding to level C recommendations is not necessarily provided

ISSN: 1471-2393