Gestational Weight Gain During the COVID-19 Pandemic

Abstract

Introduction

: Healthy gestational weight gain (GWG) is associated with improved pregnancy and delivery outcomes. The COVID-19 pandemic changed eating behaviours and physical activity, and thus may have impacted GWG. This study examines the impact of the COVID-19 pandemic on GWG.

Methods

Participants (N = 371, 86% of the larger study) were part of a study focused on GWG among TRICARE beneficiaries (i.e., active-duty military personnel and other beneficiaries). Participants were randomized to two treatment groups (GWG intervention (n = 149 pre-COVID and n = 98 during COVID), and usual care condition (n = 76 pre-COVID and n = 48 during COVID). GWG was calculated as the difference between screening weight and at 36 weeks gestation. Participants who delivered prior to the COVID-19 pandemic (March 1, 2020, N = 225) were compared to participants whose pregnancies occurred during the pandemic (N = 146).

Results

We found no significant difference in GWG between those who delivered prior to the pandemic (11.2 ± 4.3 kg) and those whose pregnancies occurred during COVID-19 (10.6 ± 5.4 kg), with no effect of intervention arm. While excessive GWG was higher pre-COVID (62.8%) than during the pandemic (53.7%), this difference was not significant overall or by intervention arm. In addition, we found lower attrition during the pandemic (8.9%) than in the pre-COVID period (18.7%).

Discussion

In contrast to prior research that indicated challenges with engaging in health behaviors during the COVID-19 pandemic, we found that women did not have increased GWG or higher odds of excessive GWG. This research contributes to our understanding of how the pandemic impacted pregnancy weight gain and engagement in research.

On March 11, 2020, the World Health Organization (WHO) declared the COVID-19 outbreak as a global pandemic (World Health Organization, 2020). Between March 1 and May 31, 2020, 42 US states and territories had ‘stay at home’ orders in place (Moreland et al., 2020). Many stores, restaurants and gyms closed (Arnold, 2020), while an increase in home deliveries altered food habits and outside exercise increased among young Americans (Pew Research Center, March 30, 2020). In-person healthcare was limited for routine issues (Santoli, 2020), including obstetric care, and even when available, people avoided attending in-person appointments out of fear of the virus (Czeisler et al., 2020). By March 30th schools were closed, and women were more likely than men to say the pandemic had significantly impacted their personal lives (Pew Research Center, March 30, 2020). These dramatic and sudden lifestyle changes may have altered weight management practices among pregnant women.

Excessive gestational weight gain (GWG) is determined based on the National Academy of Medicine’s guidelines and is tailored to pre-pregnancy BMI category (Institute of Medicine, 2009). Excessive GWG is associated with risk for multiple adverse pregnancy and neonatal outcomes, including gestational diabetes, fetal macrosomia and obesity of the child in later life (McDowell et al., 2019). However, insufficient GWG is also associated with risk of adverse pregnancy and neonatal outcomes, including preterm birth and low birth weight (Farias et al., 2021; McDowell et al., 2019). Therefore, achieving healthy GWG is important for the mother and child; however, there has been limited research on how the sociocultural changes during the pandemic affected GWG.

Previous research found that women in Beijing who were pregnant during early waves of the pandemic had higher rates of both insufficient and excessive GWG than those who gave birth before the pandemic (Du et al., 2021), which may have been due to sedentary behavior and a less healthy diet based on more infrequent interactions with their health care providers (Du et al., 2021). Another study found a significant increase in GWG during the lockdowns in Austria, again hypothesizing that sedentary behavior coupled with increased stress and emotional eating most likely resulted in the weight gain (Kirchengast & Hartmann, 2021). Indeed, women in China who had given birth in more severely affected areas (i.e., areas with lockdowns, Southern China and Wuhan) reported more emotional eating than those living in areas without COVID restrictions (Northern China) (Zhang et al., 2020). When levels of exercise and sociodemographic factors were controlled for in this study, they found a higher emotional eating score was associated with excessive GWG and the relationship was moderated by diet, with increased intake of carbohydrates and oils being associated with higher emotional eating and GWG (Zhang et al., 2020). In addition, more than 1/3 of pregnant women in the United States reported increased stress as a result of the pandemic (Moyer et al., 2020), and a review of 17 studies found a significant increase in symptoms of depression and anxiety as well as new, COVID-specific worries in pregnant women (Ahmad & Vismara, 2021; Braig et al., 2020). Previous research has found that pregnancy-specific stress is associated with higher overall GWG, likely moderated by emotional eating (Braig et al., 2020).

In the current study we examine how the COVID-19 pandemic may have affected GWG and consider how differences in participation in a behavioral weight management intervention may affect this relationship. We hypothesized participants would have higher GWG and higher rates of excessive GWG during the pandemic than in those who were pregnant prior to pandemic, consistent with previous research.

Methods

Participants were part of a larger study (N = 430) testing the effect of interventions targeting GWG and/or postpartum weight loss, that has been described elsewhere (Estevez Burns, 2022; Fahey et al., 2018). Briefly, the study randomized participants to stepped-care, phone-based interventions focused on behavioral strategies to prevent excessive GWG and/or postpartum weight loss. The participants who received the GWG intervention had less total GWG and were less likely to be classified as having excessive GWG compared with those who did not receive the GWG intervention (Estevez Burns, 2022).

Participants

For the overall trial, inclusion criteria were: being TRICARE beneficiaries (i.e., the health insurance provider for active-duty military personnel, spouses or other dependents) who were 18 years and older. Participants were also eligible if they were less than 12 weeks gestation at the screening visit and less than 13 weeks and 5 days gestation at randomization. Women with underweight were excluded given the infrequency of this BMI category in this population. Exclusion criteria included: women with medical conditions that may make dietary and physical activity changes unsafe, or those that may impact weight, women with a high-risk pregnancy (e.g., multiple gestation), women who regularly smoked within 6 months prior to conception, use of medication affecting weight, unmanaged psychiatric conditions (e.g., depression, schizophrenia, eating disorders), recent substantial weight loss (i.e., > 4.5 kg in the past 3 months), or bariatric surgery.

At the outset of the study, participants were required to be patients at one of two obstetric clinics; however, in April 2020, we adopted a remote assessment protocol due to the COVID-19 pandemic. With the closure of one of the original obstetric clinics in October 2019 and the remote assessment protocol due to the pandemic, we expanded recruitment in July 2020 to two additional obstetric clinics. Participants were initially eligible only if they had at least 1.5 years left in their current duty station to reduce the likelihood of attrition at the in-person follow-up visits, but this inclusion criterion was removed in April 2020 when remote assessments were approved.

For this analysis, participants were assigned to the pre-COVID group (n = 225) if they gave birth prior to March 1, 2020, and participants were assigned to the “during COVID” group (n = 146) if they were randomized after March 1, 2020. Participants already randomized prior to March 1, 2020 and whom gave birth after March 1, 2020 (n = 59, 13.7% of the larger sample) were excluded from these analyses, as some but not all of their pregnancy occurred during the pandemic. March 1 was used as the cut-off date, because U.S. states and territories started instituting “stay at home” orders on March 1, 2020 (Moreland et al., 2020).

Recruitment and Screening

Interested individuals were recruited between February 2017 to October 2020 via posters, pregnancy orientation visits within obstetric clinics, listserv advertisements, referrals from health care providers, and word-of-mouth. Potentially eligible participants presented for a screening visit where full eligibility was assessed, informed consent was obtained, and study measures were collected. Participants were then asked to track their diet and exercise for one week with MyFitnessPal, submit their military fitness scores (if they were active duty), and obtain their obstetrician’s clearance for participation. Once participants completed these tasks, they were eligible to be randomized (at the baseline visit).

Measures

All measures were obtained by unblinded data collectors at screening, baseline, 32-weeks gestation, and 36-weeks gestation unless otherwise indicated. Data were collected 2017–2021 in military obstetric clinics (prior to April 2020) and remotely during the COVID-19 pandemic using e-scales and electronic questionnaires.

Sociodemographic Characteristics

Self-reported sociodemographic characteristics (i.e., age, race, ethnicity, military rank, parity) were collected at the screening visit. Analyses were conducted based on demographic categories of military status (i.e., active duty, dependent), ethnicity, race (i.e., White, Black, or other), and parity (i.e., previous live birth or no previous live birth).

COVID-19 Diagnosis

If a confirmed COVID-19 diagnosis occurred for a study participant at any data collection visit, intervention session, or participant communication, it was recorded as an adverse event.

Anthropometrics

Weight change (kg) during pregnancy was the primary dependent measure. Weight was measured without shoes in light clothing, on a calibrated digital scale (Tanita BWB 800 S) or on their Body Trace e-scale during the COVID-19 pandemic, which was cellularly transmitted to the study team. Previous research has demonstrated the comparability between clinic and Body Trace e-scale weights (Pebley et al., 2019). The primary outcome was GWG at 36-weeks gestation. For those that did not have their GWG outcome measured at 36 weeks, the 32-week weight was used, for only those participants that delivered before week 36. Excessive GWG was defined consistent with the National Academy of Medicine’s guidelines (i.e., > 16 kg for women with normal weight, > 11.5 kg for women with overweight, > 9 kg for women with obesity) (Institute of Medicine, 2009). Height was measured in centimeters using a stadiometer at screening or self-reported during the COVID-19 pandemic. BMI was calculated using the standard formula, using the weight obtained at the screening visit as a proxy for pre-pregnancy BMI (Krukowski et al., 2016).

Study Engagement

Completion of the 36-weeks gestation visit (or the 32-week visit, if the participant delivered prior to 36 weeks) was coded dichotomously (yes/no). Study interventionists monitored participant engagement in phone-based intervention sessions; the total number of sessions in the gestational period were summed for the analyses.

Statistical Analysis

Statistical analyses were performed with SAS/STATv14.2 (SAS Institute Inc., Cary, NC). Descriptive statistics including means, standard deviations, and proportions were generated for all variables. To initially examine the difference in mean values of GWG between the two groups of interest (i.e., pre-COVID vs. during COVID), we applied two-sample t-test. This comparison was only conducted on participants (n = 316) who completed the outcome visit at the end of pregnancy (i.e., 36-weeks gestation visit or the 32-week visit, if the participant delivered prior to 36 weeks). Analyses were performed for the overall sample, and separately for the pre-COVID-19 and during COVID-19 groups, by GWG intervention condition or the comparison condition (which did not receive any behavioral intervention during pregnancy). Differences and associations were considered statistically significant at the alpha level of 0.05.

Results

A sample of N = 371 were included in the current analyses (Table 1). The majority of participants identified as white (56.9%), 15.1% identified as Black, and 28.0% of participants identified as another race group. Approximately 17% of participants identified as Hispanic. Participants were distributed across the following BMI categories (as measured at the screening visit): 32.9% with normal weight, 39.6% with overweight, and 27.5% with obesity. 47.4% of participants were active-duty personnel. Only 8 cases of COVID-19 were reported during the gestational period. Attrition was 18.7% in the pre-COVID group and 8.9% in the “during COVID” group (p = .0097); there were significant differences between the COVID groups in missing data with more data missing pre-COVID compared to during COVID, overall and for the GWG arm, but not for the comparison arm (Table 2). Examination of engagement found that individuals attended fewer intervention sessions “during COVID” than pre-COVID (pre-COVID: M = 5.5 (SD = 2.4), vs. during COVID: M = 4.7(SD = 2.4), p < .001).

Table 1.

Participant characteristics

	Overall		GWG intervention		Comparison condition
	Pre-COVID (N = 225)	During COVID (N = 146)	Pre-COVID (N = 149)	During COVID (N = 98)	Pre-COVID (N = 76)	During COVID (N = 48)
Age (years, Mean (SD))	30.7 (5)	30.5 (4.7)	30.9 (5.1)	30.3 (4.6)	30.2 (4.7)	30.9 (4.9)
Body mass index at screening (kg/m2) (Mean (SD))	27.6 (4.9)	27.9 (6)	27.5 (4.8)	27.8 (5.2)	27.7 (5.2)	28.1 (6.4)
Gestation week at screening (weeks, Mean (SD))	11.5 (1.1)	12 (1.0)	11.6 (1.1)	12.1 (1)	11.4 (1.2)	11.9 (1.0)
Weight at screening (kg, Mean (SD))	73.7 (14.2)	75.5 (17.1)	73.3 (13.7)	74.8 (16.4)	74.4 (15.2)	76.9 (18.6)
BMI category (%)
Normal weight	32.4	33.6	32.2	34.7	32.9	31.3
Overweight	39.6	39.7	40.3	38.8	38.2	41.7
Obesity	28.0	26.7	27.5	26.5	28.9	27.1
Hispanic/Latino (%)	16.9	17.8	14.8	15.3	21.1	22.9
Race (%)
White	58.7	54.1	57.7	57.1	60.5	47.9
Black	15.6	14.4	16.8	11.2	13.2	20.8
Other race groups	25.8	31.5	25.5	31.6	26.3	31.3
Active duty (%)	49.8	43.8	49.0	46.9	51.3	37.5
Previous live birth (%)	56.0	56.9	55.7	57.1	56.6	56.3
Mean (SD) or %

Table 2.

Unadjusted differences in mean GWG and excessive GWG between pre-COVID and during COVID.

	Overall			With GWG intervention			Comparison intervention
	Pre-COVID (N = 225)	During COVID (N = 146)	p-value	Pre-COVID (N = 149)	During COVID (N = 98)	p-value	Pre-COVID (N = 76)	During COVID (N = 48)	p-value
Gestational Weight Gain (kgs, Mean (SD))	11.2 (4.3)	10.6 (5.4)	0.2807	10.9 (4.2)	10.1 (5.0)	0.2352	11.8 (4.3)	11.6 (6.1)	0.8687
Excessive Gestational Weight Gain (%)	62.8	53.7	0.1007	59.2	52.8	0.3517	69.1	55.6	0.1422
Missing Data (%)	18.7	8.9	0.0097	20.8	9.2	0.0153	14.5	8.3	0.3071

Mean (SD) or %

The “during COVID” group had slightly lower GWG compared to the pre-COVID group overall (pre-COVID: M = 11.2 (SD = 4.3), vs. during COVID: M = 10.6 (SD = 5.4)) (Table 2). However, this difference was not statistically significant overall or within either of the treatment conditions. Similarly, the rate of excessive GWG was higher pre-COVID compared to during-COVID period but was not statistically significant overall (pre-COVID: 62.8%, during COVID: 53.7%, p = .10), or within either of the treatment conditions (Table 2).

Discussion

The current study explored the effects of the COVID pandemic on GWG among TRICARE beneficiaries and examined how being involved in an intervention targeting healthy GWG may have been impacted by the pandemic. We found no overall significant differences in GWG between pregnancies that occurred pre-COVID and during COVID, overall, among the women who received the GWG intervention and the women who did not receive intervention during pregnancy.

Interestingly, we observed a significantly higher percentage of participants completed the assessment visit at the end of pregnancy during the pandemic than did prior to the pandemic. It is possible that participants felt greater dedication to medical research (Cardel et al., 2020) or were more concerned with their health and so were more likely to complete the program during the pandemic. However, we found that although participants were more likely to complete the data collection visit, individuals attended fewer intervention sessions during the pandemic. Notably, data collection visits changed modalities from in-person to remote, whereas intervention sessions were always conducted via phone. The remote assessment modality during the COVID-19 pandemic may have made completing the visit easier for participants (Ross et al., 2021). However, lifestyle changes in the pandemic such as additional caregiving responsibilities may have prevented attendance at sessions.

Data on weight management behaviors during the pandemic have been mixed. Objective data from Fitbit (Fitbit, 2020), smartphone-integrated accelerometers (Tison et al., 2020) and self-reported physical activity (Flanagan et al., 2021) indicate a significant worldwide decrease in physical activity at least in the first several months of the pandemic. In contrast, research indicates that overall healthy eating may have improved with more cooking at home and less eating out (Flanagan et al., 2021). However, research focused on those with obesity found self-reported poorer eating (Almandoz et al., 2020) and increases in weight during the pandemic (Flanagan et al., 2021). In addition, individuals involved in behavioral intervention research reported the pandemic made it more difficult to engage in recommended health behaviors (Cardel et al., 2020). In contrast to this previous literature and our hypotheses, however, we found that participants in this study had slightly lower, albeit non-significant, GWG during the COVID pandemic, which could have been due to the high level of exercise in this population (Pebley et al., 2022) and potentially extra time to exercise and cook at home during the pandemic. In addition, we also demonstrated that some research studies, like the current study, may have better retention and remained just as effective during the pandemic.

The current study has several strengths, mainly due to the robust randomized controlled design of the original study investigating the effects of a GWG intervention. The pandemic was, by its nature, an unpredictable event, and a strength of this study is that we were able to examine the impact of the pandemic on GWG, in real time. However, generalizability of our findings to civilian populations and individuals with class II and class III obesity is unknown; it will be important to examine more broadly the impact of the pandemic on GWG and participation in pregnancy-related interventions. In addition, it is possible that changes in participant characteristics recruited in the pre-COVID and during COVID periods may have impacted our findings.

In conclusion, the major findings in this study were no significant differences in GWG during the COVID pandemic compared to the pre-COVID period, in contrast to previous research indicating weight gain, lower levels of physical activity, increased dietary intake, and high stress in the general population during the pandemic. In addition, we found significantly lower attrition during the COVID pandemic, particularly among women who received the GWG intervention. This research contributes to the existing literature around GWG during the pandemic by demonstrating that, for some populations, the pandemic was not associated with greater GWG and may have actually improved engagement in research.

Funding

The study was funded by the National Institute of Diabetes and Digestive and Kidney Diseases (R01 DK104872) of the National Institutes of Health, with the title of “Behavioral Weight Management for Pregnant and Postpartum Women in the Military” (Krukowski, Principal Investigator).

Declarations

Conflicts of interest

The authors declare no conflict of interest. The research represents a Collaborative Research and Development Agreement with the United States Air Force (CRADA #18-282-59MDW-C19002). The opinions expressed in this document are solely those of the authors and do not represent an endorsement by or the views of the United States Air Force, the Department of Defense, or the United States Government. The views expressed are those of the authors and do not reflect the official views or policy of the Department of Defense or its Components.

The voluntary, fully informed consent of the subjects used in this research was obtained as required by 32 CFR 219 and DODI 3216.02_AFI 40–402.

Ethical Approval

The trial is registered on clinicaltrials.gov (NCT 03057808). The protocol was approved by the Institutional Review Board (IRB) of the 59th Medical Wing and acknowledged by the University of Tennessee Health Science Center IRB. A detailed description of this study’s methods and rationale has been published (Fahey et al., 2018). The study was approved by the appropriate ethics committee and have therefore been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments.