Helicobacter pylori Exposure in Nausea and Vomiting of Pregnancy Increases Risk of Preterm Delivery

Table 1

Diagnostic codes and prior evidence for associations with nausea and vomiting of pregnancy, H. pylori, and preterm delivery. The cited literature in this table represents manual selection and is not intended to reflect a complete or systematic literature review. The associations may be either positive or negative and were not necessarily causative or detected in all relevant prior studies. Asterisk indicates that all subclassifications under the indicated category were included.

Diagnosis	ICD codes	Association evidence in prior studies
		NVP (Ref.)	HP (Ref.)	Preterm delivery (Ref.)
Vomiting in pregnancy	O21; R11	N/A	Yes [9, 10]	Yes [2]
Hyperemesis gravidarum	O21.1
Low birth weight	P07	Yes [17]	Yes [15]	Yes [32]
Preterm delivery	O60.1	Yes [2]	Yes [33]	N/A
Second trimester preterm delivery	O60.12
Obesity/overweight	E66	Yes [34]	Yes [35]	Yes [36]
Multiparity-associated	Z64.1; O09.4	Yes [37]	No	Yes [38]
Housing and economic problems	Z59	Yes [3]	Yes [24]	Yes [26]
Education and literacy problems	Z55
Tobacco, alcohol, other drug use	Z72.0; F10-19	Yes [34]	Yes [39]	Yes [26]
High-risk pregnancy	O09	Yes [40]	No	Yes [41]