Shared eating habits of couples impact pregnancy weight gain, study suggests

In a recent article published in the journal Nutrients, researchers assessed how gestational weight gain (GWG) is associated with the eating behaviors of pregnant people and their non-pregnant partners through a cohort study in the United States.

Their results indicate that poor cognitive restraint was associated with higher GWG, suggesting that restrained eating by couples could reduce GWG and, therefore, the risk of infant macrosomia, cesarean section, pre-eclampsia, and gestational diabetes mellitus (GDM).

Study: Healthful Eating Behaviors among Couples Contribute to Lower Gestational Weight Gain. Image Credit: El Nariz / Shutterstock

Background

Excess GWG is associated with increased risks of infant macrosomia, pre-eclampsia, cesarean section, and GDM. It is also associated with pre-gravid body mass index (BMI), and diet-centric interventions during pregnancy are effective in reducing GWG.

Though pregnancy is often associated with eating and snacking more, less is known about what eating behaviors may contribute to excess GWG. The influence of the eating habits of the non-pregnant partner has also not been studied.

About the study

In this study, researchers theorized that the non-pregnant partner can influence household food consumption and encourage healthy eating attitudes and food habits during pregnancy.

They hypothesized that the couple’s behaviors would be most strongly linked with GWG, followed by the pregnant person’s behaviors alone. They expected to see the weakest association between the non-pregnant person’s behaviors and GWG.

Pregnant people included in the study had a BMI between 18.5 and 35, were over 21 years old, had only one other child, and were either planning their pregnancy or had a gestational age of under 10 weeks.

People receiving fertility treatments, with existing medical conditions, taking medications such as insulin, which could influence fetal growth, drinking alcohol, or smoking during pregnancy were excluded.

Demographic factors such as marital status, age, ethnicity and race, individual income, and educational attainment were included. The pregnant person’s weight and GWG were measured during the first and third trimesters, while the partner’s weight was measured once. Weight and height were used to calculate the BMI, while GWG was classified as normal, overweight, or obese.

An eating inventory was used to assess eating behaviors and attitudes, such as perceived hunger, dietary disinhibition, and cognitive restraint. A higher score for each of these components indicated poorer eating behavior. A couple’s score was calculated as the average of the two individual scores.

The perceived hunger component scored between 0 and 14, assesses how susceptible an individual is to feelings of hunger, while dietary disinhibition (0-18) evaluates the tendency to overeat palatable foods. The cognitive restraint component (0-21) examines an individual’s ability to restrict their food intake for weight maintenance.

During data analysis, adjusted general linear models were used to examine statistical associations and odds ratios were calculated.

Findings

The study included 218 pregnant persons (average age 30.3) and 157 non-pregnant partners (average age 31.4). The average BMI for pregnant persons was 26.1, while the partners had an average BMI of 28.5. Non-pregnant partners were more likely to be obese, earn more than USD 40,000, and be at least college graduates.

For the entire cohort, the mean GWG was 11.8 kg, and nearly half showed excess GWG. Only one in three pregnant people with normal weight experienced excess GWG compared to 63% of overweight people and 52.2% of obese people.

Nearly 57%, 86%, and 89% of pregnant participants received low scores on the cognitive restraint, dietary disinhibition, and perceived hunger components, respectively. People with normal weight were more likely to receive low scores. Non-pregnant partners received, on average, lower scores than their partners, indicating healthier eating habits.

Results from the unadjusted models showed that higher scores for each of the components were associated with higher GWG. The association remained significant for the cognitive restraint score after adjusting for BMI during early pregnancy and demographic factors.

There were no significant associations between the non-pregnant partner’s scores and GWG. However, there was a significant positive association between a couple’s score for cognitive restraint and GWG. Specifically, if cognitive restraint increased by one unit, GWG increased, on average, by 0.23 kg; this finding persisted after adjusting for BMI and demographic factors.

Conclusions

Findings from this study indicate that cohesive partnerships can foster better eating behaviors and lead to optimal GWG. The implication is that involving both partners in dietary interventions could lead to better outcomes than if the pregnant person alone is targeted.

One limitation of this study is that it did not assess dietary or energy intake, which could be predicted by eating behavior. Sleep and physical activity, which may both contribute to GWG, were also not accounted for in this analysis.