Table.

GRADE evaluation of interventions for constipation, haemorrhoids, and heartburn in pregnancy

Important outcomes	Symptom relief, quality of life, adverse effects
Number of studies (participants)	Outcome	Comparison	Type of evidence	Quality	Consistency	Directness	Effect size	GRADE	Comment
What are the effects of interventions to prevent or treat constipation in pregnancy?
1 (40)	Symptom relief	Increased fibre intake v no treatment	4	–1	0	–2	+2	Moderate	Quality point deducted for sparse data. Directness points deducted for unspecific definition of constipation and for few comparators. Effect-size point added for odds ratio less than 0.2
1 (140)	Symptom relief	Stimulant laxatives v bulk-forming laxatives	4	–3	0	0	+1	Low	Quality points deducted for sparse data, uncertainty about randomisation, and no clear end-point. Effect-size point added for odds ratio less than 0.5
What are the effects of interventions to prevent or treat haemorrhoids in pregnancy?
2 (150)	Symptom relief	Rutosides v placebo	4	–2	0	0	+2	High	Quality points deducted for sparse data, and for not reporting method of randomisation. Effect-size points added for RR less than 0.2
What are the effects of interventions to prevent or treat heartburn in pregnancy?
1 (50)	Symptom relief	Antacids v placebo	4	–1	0	0	0	Moderate	Quality point deducted for sparse data

Type of evidence: 4 = RCT; 2 = Observational; 1 = Non-analytical/expert opinion. Consistency: similarity of results across studies Directness: generalisability of population or outcomes Effect size: based on relative risk or odds ratio