Weight Loss and Physical Fitness Following Pregnancy in Active Duty Women

Overview

Pregnancy and delivery are major stressors on the female body and contribute significantly to permanent weight gain and associated morbidity in women. This can profoundly affect the ability of active duty (AD) women to advance in their career. The first 12 weeks postpartum are the time period during which the most significant weight loss occurs and is critical in achieving a healthy weight in the first year postpartum. Many factors contribute to effective weight loss in this period among which the most critical are diet, exercise, and sleep. Breast feeding and depression may also affect weight changes postpartum. Research has shown diet to likely be the most crucial of these factors. The PADaWL study is designed as a randomized controlled trial to assess the effects of dietary intervention on weight and physical fitness versus routine postpartum care in the first year postpartum. Subjects will be primiparous AD women from any military service recruited in the obstetric clinic in the third trimester of pregnancy at Tripler Army Medical Center. Data will collected in an ambi-directional fashion with pre-pregnancy physical fitness data, demographic and pregnancy data collected at time of enrollment. Subjects will be randomized to receive intensive virtual sessions with a dietician vs routine postpartum care for the first 12 months postpartum. We will utilize a biometric device to monitor activity levels and sleep, web-based diaries to monitor breast feeding and diet, and validated questionnaires to evaluate depression as well as diet and sleep. Subjects will be monitored weekly for the first 12 weeks postpartum and will then be further evaluated at 6, 9 and 12 months postpartum. Primary outcome is weight at 12weeks postpartum and whether subjects have achieved military standards. Secondary outcome will be weight at 12 months postpartum and whether subject has achieved weight and fitness standards. The study intends to collect large amounts of data, and we intend to analyze which factors may be contributing to weight retention postpartum. This study should provide an accurate assessment of the effects of pregnancy on AD women. It should generate a clean and accurate dataset on which multiple follow-on studies can be performed and provide data for designing further intervention studies in postpartum women. The results of this study should also be able to assist in developing policy and guidance concerning AD women and pregnancy.

RESEARCH BACKGROUND: Women naturally gain weight beyond that of the added pregnancy tissue and many gradually lose this excess weight following delivery. In the US, 15-27% of women across all ethnic groups have excess postpartum weight retention (PPWR) of \> 10lbs one year after delivery. (Lipsky, Strawderman, and Olson 2012, 1496-1502); (Gunderson et al. 2008, 178-187); (DeGroot et al. 2021a, e0255248) This issue has also been documented in AD women across multiple services with 12-15% not meeting fitness standards at one year postpartum. (DeGroot et al. 2021b, e0255248) (Rogers et al. 2020, e227-e234) This is an immediate concern for AD women as it has a detrimental effect on career progression. Weight retention also has long-term consequences for health including contributing significantly to the risk of obesity, diabetes, heart disease and hypertension. It is shown that women who return to their pre-pregnancy weight by about six months have a lower risk of being overweight 10 years later. (Amorim Adegboye and Linne 2013, CD005627) This critical postpartum time period in a woman's life has major repercussions on her well-being. A significant number of women are never able to effectively lose weight and achieve fitness postpartum. Long-term, the added weight and resulting metabolic effects of postpartum weight retention lead to chronic health conditions such as obesity type II diabetes, chronic hypertension and other components of metabolic syndrome. (Linne et al. 2003, 1516-1522) Many AD women succumb to this cycle of weight retention and are unable to serve effectively in the military. This affects 10-20% of AD women who become pregnant while serving and was highlighted by retrospective research performed at Tripler Army Medical Center. (DeGroot et al. 2021a, e0255248) Our literature review reveals five factors that contribute significantly to weight changes following delivery in AD women: diet, exercise, breastfeeding, sleep and depression. RESEARCH GOALS AND OBJECTIVES: The PADaWL study seeks to determine if dietary interventions by a licensed dietician in the first year postpartum will lead to more effective weight loss and ultimately physical fitness than routine postpartum care among a cohort of AD service members. The primary goal of this research is to determine how effectively AD women lose weight and recover fitness after delivery. Specifically, aims of this study are to: Aim#1: Identify factors that influence the timing of active duty servicewomen return-to-duty fitness postpartum. Aim #2: Characterize the utility of a biometric device to monitor multi-factorial influences on achieving pre-pregnancy fitness postpartum Aim #3: Determine the effectiveness of intensive dietary counseling in the first year postpartum on weight loss and physical fitness. STUDY PROCEDURES: I. Recruitment will be performed using multiple methods and can be recruited at any time during their pregnancy: Passive recruitment will occur in the TAMC OB/GYN clinic. Posters will be displayed throughout the OB/GYN clinic with tabs showing phone numbers allowing the patients to contact researchers directly to inquire about the study. Active recruitment will occur in the TAMC OB/GYN clinic. Providers will directly ask AD women who are obstetric patients whether they are interested in participating and direct them to the research staff. If necessary, appointments in MHS Genesis will be screened for healthy primiparous AD women with an uncomplicated singleton pregnancy who would be candidates for the study. II. Screening for Eligibility: Potential participants will be approached and screened for inclusion and exclusion criteria by either one of the researchers or research assistants. This will be done via telephone call. If they are interested in participating in the study, they will be sent a flyer detailing the study via email. If they maintain interest in participating in the study, they will be asked to meet with the research team at the time of their 34-37week appointment. III. Enrollment: Eligible potential participants will meet a member of the research team either before or after their 34-37week appointment. They will bring a copy of their pre- pregnancy fitness report. During this appointment they will be rescreened. Informed Consent and HIPPA consent will be obtained. Randomization will occur. Subjects will be assigned a de-identified study subject number. An anonymous myfitnesspal.com account will be opened, and they will be asked to familiarize themselves with the website. Subjects will be asked to obtain a scale for home use. Subject will be given a hand- out on all the data which will be collected on her during the course of the study. IV. Data collection at Enrollment: After signing the consent, subjects will be asked to complete questionnaires on fitness and diet during their pregnancy. These questionnaires will be on-line, and they will enter their data utilizing their anonymous study ID. A demographic, cultural and social questionnaire will be obtained. V. Retrospective Data collected after Enrollment: Weight gain in pregnancy, Conditions complicating pregnancy, EPDS score at 28weeks VI. Delivery: All AD women participants in the PADaWL study coming to TAMC L\&D for their delivery after 35 weeks will be identified based on the posted website list, via screening of patients on the postpartum ward, or will contact research personnel via telephone call or text. Lipid profile labs will be drawn at the time of their admission with the remainder of their obstetric labs. Subjects will deliver their newborn and after stabilization will be transferred to the postpartum ward. On postpartum day #1 or #2, the subject will be approached by the research team in the postpartum ward. Subjects will be given the Garmin fitness tracker and given instructions on use. The subject will use their initials and only their birthday year to set up the app. She will be asked to start recording diet and activity levels (primarily measured as steps and caloric expenditure) on the day after being discharged from hospital. She will be given repeat instructions on appropriate monitoring of diet and exercise. Before discharge she will obtain a 6-week postpartum appointment with one the researchers. Intervention group will obtain their first virtual nutrition counseling appointment to occur within the first month postpartum VII. Randomized groups to active vs routine dietary management: Both groups will receive the following: Nutrition education handouts pertaining to healthy postpartum eating, Nutrition education handouts pertaining to calorie counting procedures to include websites, apps, and methods of estimating caloric intake, General calorie recommendations based on participant age, height, weight, and activity level Intervention group will receive: One-on-one appointments with a Registered Dietitian via virtual health within the first month postpartum, three months postpartum, six months postpartum, and 12 months postpartum VIII. First 12 weeks postpartum: Period of intense data collection: All subjects will be collecting daily diet information via myfitnesspal.com. All subjects will be collecting activity as well as sleep levels via the Garmin fitness tracker. This data will be downloaded automatically to the website via their smart phone. All subjects will document her breast feeding weekly in the myfitnesspal.com app. All subjects will obtain weekly weights and place data onto their myfitnesspal.com website. The intervention group will have a virtual nutrition counseling appointment within the first month postpartum and a second appointment in the third month postpartum. At the 6- week postpartum appointment with one of the research investigators, subjects will submit a EPDS questionnaire to assess depression. This weekly data will be collected through their 12weeks postpartum. The data will be accessible by the research personnel via the internet. If data is missing, the subject will be contacted by research personnel to improve compliance. IX. 6 months postpartum: Subjects will undergo telephonic interview with research team. The following data will be obtained: Weight, Dietary questionnaire, Fitness questionnaire, Sleep questionnaire, EPDS, Breast feeding data, The intervention group will have a 3rd virtual nutrition counseling in this timeframe. X. 9 months postpartum: The intervention group will undergo a fourth and final virtual nutrition counseling appointment in this timeframe. XI. 12 months postpartum: The patient will undergo her first military fitness evaluation for record at 1 year postpartum including weight and height. She will be asked to bring a copy of these data to her 12month postpartum visit. XII. 12 months postpartum: Subjects will undergo a clinic visit with physical exam with one of the research investigators. In addition, they will submit the following data: Weight, Dietary questionnaire, Fitness questionnaire, Sleep questionnaire, EPDS, Breast feeding data, Post-study questionnaire. The intervention group will have a final virtual nutrition counseling appointment. STAISTICAL ANALYSIS Aim#1: The outcomes evaluated are 1) the ability of AD women to achieve military weight standards at 12 weeks, 6months and 1 year postpartum, and 2) improvement in mandated physical fitness assessment at 12 months postpartum. Odds ratio and t-test will be used to compare pre-pregnancy and postpartum fitness results for the collective enrollment. ANOVA with repeated measures over time will be used to evaluate differences between pre pregnancy, at delivery, and different time points post pregnancy for weight. Regression analysis will be used to determine the linear regression algorithm for weight loss over time for each participant from delivery through up to one year postpartum to determine the x intercept of the time point when weight equals pre pregnancy weight for each participant. This time period of return to pre pregnancy weight can be used along with percent weight loss at 12 weeks post pregnancy as the metrics to examine the relationship with other variables of sleep, breast feeding, activity, etc.Multiple variate stepwise regression analysis will be used to identify which variables most strongly independently influence weight loss (period of time before pre pregnancy weight is achieved, and/or percent weight loss at specific timepoints (1eg. 2 weeks, 6 months, 1 year) from delivery date). Which variables are covariates with other variables will also be determined. Aim #2: The efficacy of the fitness tracker to monitor postpartum women as they regain fitness in the year after pregnancy will be evaluated based on 1) the ability to generate consistent useable data, and 2) the acceptance by the study participants as a wearable device Descriptive statistics will be used to characterize how many events of interrupted data or non-collected data missing data occurs each week for 12 weeks postpartum Aim #3: Determine the effectiveness of intensive dietary counseling in the first year postpartum on weight loss and physical fitness. To test the effectiveness of dietary intervention the participants will be randomized to two groups. Group 1 (n=32) will receive routine postpartum care. Group 2 (n=32) will receive dietary interventions by a licensed dietician. The metric for efficacy of the intervention will be detecting an effect size of 20% in weight, sleep score, breast feeding score ANOVA will be used to compare the two groups with repeated measures over time at 16 time points over time (pre-pregnancy, time of delivery, weekly for 12 weeks, 6 months and 12 months postpartum) for weight, sleep score, breast feeding score. For fitness and activity ANOVA at two time points (pre-pregnancy and 12 months postpartum) by group interaction effect will be analyzed. An addendum was approved on 27 AUG 2025 in which we ask participants in the PADaWL study to undergo physiologic testing at the Armed Forces Wellness Center at between 12-18 weeks postpartum and 1 year postpartum. These phyisologic tests will be measuring body fat % and CO2 max. These data will be included in the analysis. This part of the protocol is optional for all participants.