Findings from previous studies on changes in dietary intake caused by NVP have been inconsistent.
To investigate the association between NVP and dietary nutrient intake in Chinese pregnant women, a study based on data from a cross-sectional survey conducted from 2019 to 2020 was carried out.
The study was funded by Inner Mongolia Dairy Technology Research Institute Co Ltd, a subsidiary of Chinese diary giant Yili Group.
A total of 303 healthy pregnant women aged between 20 and 45, who were in their first trimester and came from 10 urban Chinese cities, were recruited for the survey.
After completing the face-to-face survey, the participants were divided into an NVP group and a non-NVP group. The former was then subdivided according to the women’s self-evaluation of severity.
Some 84.1% were included the NVP group, of which 62.4%, 25.9% and 11.8% were in the mild, moderate and severe subgroups respectively.
The findings also indicated that pregnant women in Beijing and Guangzhou were more likely to experience NVP.
The participants’ dietary nutrient and food intake were collected via a 24-hour dietary recall and a 36-item semi-quantitative food frequency questionnaire (SFFQ).
Compared to those in the non-NVP group, women in the NVP group were found to have lower intake of nutrients, including carbohydrate, protein, fat, vitamins A and E, thiamin, niacin, potassium, manganese, iron, and zinc.
Specifically, significant differences were discovered in the intake of riboflavin, calcium, phosphorus and selenium.
“The effects of NVP on dietary nutrient intake varied among the three subgroups. The more severe the NVP symptoms, the lower the dietary nutrient intake,” said the authors.
Serious consequences
Globally, about 35% to 91% of pregnant women experience varying degrees of NVP.
According to this study, the moderate and severe NVP groups tended to have a greater decrease in food intake. The latter also showed insufficient and a slower rate of gestational weight gain.
Other than reduced appetites, moderate or severe NVP could also cause electrolyte and pH imbalances, poor quality of sleep and life, and even functional impairment.
These could, in turn, lead to adverse pregnancy outcomes such as preterm birth, small-for-gestational-age infants, and an increased risk of neurodevelopmental delay.
“In our study, the consumption of mushrooms, algae, nuts and seeds, meat, eggs, and dairy products in pregnant women with NVP, especially the severe NVP group, was lower than that of those with no NVP.
“These foods are typically good sources of protein and essential for foetal growth. Some women with NVP may have chosen to avoid certain foods to control their symptoms, resulting in inadequate nutrition intake,” the authors wrote.
The aversion to these foods could negatively impact the health of both mother and baby.
“Participants with NVP generally had a lower intake of B vitamins, especially thiamin and riboflavin. Multiple studies have indicated that thiamin deficiency affects foetal brain development and may result in foetal brain dysfunction.
“Likewise, insufficient riboflavin intake may affect embryonic growth and cardiac development in the infant. Studies have also reported that women with postpartum depression had lower serum riboflavin levels,” added the authors.
Nevertheless, there were several limitations to this study. Firstly, the possibility of dietary intake affecting NVP symptoms cannot be excluded.
Moreover, the symptoms were not assessed by a validated tool but were self-reported, which might have led to recall bias. An in-person interview also had a higher chance of social-desirability bias.
“Further prospective cohort monitoring is necessary to explore the relationship between NVP and dietary intake. We also need to conduct long-term observations to determine whether NVP during early pregnancy would impact nutrition intake in the middle or later stages of gestation,” the authors concluded.
Source: Nutrients
https://doi.org/10.3390/nu15040933
“Nausea and Vomiting during Early Pregnancy among Chinese Women and Its Association with Nutritional Intakes”
Authors: Shujing Zhu, et al