Nausea and vomiting in pregnancy (NVP) is common with reported rates ranging from 35% to 91% of pregnancies. Symptoms range from mild nausea to the serious condition hyperemesis gravidarum. Experiences of NVP vary greatly, but it typically begins around 4-6 weeks gestation, peaks between 8 and 12 weeks, and then diminishes so that by 20 weeks, a markedly reduced number of women suffer from it.Previous analyses in the UK Southampton Women's Survey (SWS) cohort demonstrated little overall change in dietary quality from before to early pregnancy but did not evaluate the changes according to NVP or consider changes in energy intake. Relatively little is known about the effects of NVP on diet in pregnancy, although a frequent assumption is that NVP causes a reduction in appetite and reduced food intake. The limited cross‐sectional evidence comparing NVP and reported dietary intakes reveals inconsistent associations. In a recent study, women with NVP had slightly higher intakes of fruit and vegetables and more noticeably higher intakes of sugar‐containing soft drinks than other pregnant women. In a smaller study women with NVP ate less meat and somewhat fewer vegetables than other pregnant women, whereas an ecological study across 21 countries suggested that high rates of NVP are associated with high intakes of meat, milk and eggs, and low intakes of cereals and pulses. Some of the inconsistencies in findings may be due to the use of cross‐sectional data, and reporting differences among women whose diets have changed in early pregnancy. However, none of these studies had measures of pre‐pregnancy diet to enable description of changes in diet resulting from NVP.The present study describes the effects of NVP on change in diet in a cohort of 2270 women whose diets were assessed before and during pregnancy. This provides a valuable opportunity to evaluate change in diet in pregnancy in response to NVP. We consider reported changes in the amount of food and types of foods consumed in early pregnancy, as well as effects on diet quality.