Nausea and vomiting of pregnancy: associations with personal history of nausea and affected relatives.

Purpose: To examine whether personal history of nausea or history of nausea and vomiting of pregnancy (NVP) in relatives are risk factors for a woman to suffer from NVP. Further, to evaluate if these factors are associated with the severity of NVP.

Methods: Cohort study of 2411 pregnant women recruited from maternity health care clinics. The severity of NVP was categorized according to Pregnancy-Unique Quantification of Emesis (PUQE) questionnaire into no/mild/moderate/severe NVP. History of nausea was assessed in connection with motion sickness, seasickness, migraine or other kinds of headache, after anesthesia, related to the use of contraceptives, and other kinds of nausea. History of NVP in relatives was categorized into first-degree (mother/sister) and second-degree relatives (more distant).

Results: In multivariable analysis including previous personal history of nausea, motion sickness (OR 3.17, 95% CI 1.81-5.56, p < 0.0001) and nausea in migraine (OR 3.18, 95% CI 1.86-5.45, p < 0.0001) were associated with severe NVP. History of nausea in other kinds of headache was associated with moderate NVP (OR 1.91, 95% CI 1.34-2.72, p = 0.001). Women with affected first-degree relatives had higher odds for moderate (OR 3.84, 95% CI 2.72-5.40) and severe (OR 3.19, 95% CI 1.92-5.28) NVP (p < 0.0001). All these results remained significant after adjusting for parity, body mass index, smoking, employment and age.

Conclusion: Women with personal history of nausea or family history of NVP have an increased susceptibility of NVP. This information is useful in pre-pregnancy counselling.