Longitudinal relationship of physical activity with insulin sensitivity in overweight and obese pregnant women

Physical behaviours during pregnancy may alter the association of maternal insulin sensitivity with neonatal adiposity: a prospective pre-birth cohort of mother-child pairs

BACKGROUND

Lower maternal insulin sensitivity during pregnancy is associated with greater fetal adiposity. Physical activity can improve insulin sensitivity, but it is not known if physical behaviours influence the known association of maternal insulin sensitivity with offspring adiposity. This study aimed to investigate the moderating impact of physical behaviours on this association.

METHODS

Pregnant women (n = 812) from the Gen3G cohort were recruited during the first trimester of pregnancy and followed until delivery. At the first (V1) and second trimester (V2) hospital visits, Gen3G staff measured anthropometry, and participants reported sleep duration as well as leisure physical activity and sedentary behaviour via lifestyle questionnaires. We used plasma glucose and insulin values from the 75 g oral glucose tolerance test at V2 to calculate insulin sensitivity using the Matsuda index. We recorded birthweight from electronic medical records. Among a subset of neonates (n = 265), trained research staff measured skinfold thickness using a calibrated skinfold caliper following standardized protocols to estimate neonatal adiposity. Linear regression analyses assessed the association of insulin sensitivity with birthweight z-score and sum of neonatal skinfold thickness, adjusting for maternal age, race/ethnicity, gravidity, smoking, with and without adjustment for maternal body mass index at V1. We evaluated moderation by physical activity, sedentary behaviour, or nighttime sleep duration using interaction terms and stratified analyses for the association of maternal insulin sensitivity with offspring birthweight and with offspring adiposity.

RESULTS

Lower Matsuda index was associated with higher birthweight z-score (ß±SE= -0.180 ± 0.056, p = 0.001) and with higher sum of skinfold thickness (neonatal adiposity) (ß±SE=-0.877 ± 0.383, p = 0.02) in fully adjusted models. The association between Matsuda index and sum of skinfold thickness was weaker in women with higher levels of physical activity at V2 ([high ≥ 1.26 kcal/kg/day] ß±SE=-0.15 ± 0.65) compared to women with lower levels [low < 1.26 kcal/kg/day] ß±SE=-1.36 ± 0.51, P-interaction = 0.01). We also observed potential interactions of sleep and sedentary behaviour at V2 with Matsuda index for the association with birthweight z-score. We did not observe effect modification by levels of physical behaviours assessed at V1.

CONCLUSION

The association between lower insulin sensitivity and higher neonatal adiposity was attenuated in women with higher physical activity levels in the second trimester, independent of maternal body mass index.

Effects of Physical Activity on Blood Lipids and Hemoglobin A1c in Healthy Pregnant Women: The FitMum Randomized Controlled Trial

OBJECTIVE

Maternal blood lipid and glucose concentrations during pregnancy affect fetal growth and the risk of pregnancy and delivery complications. We aimed to investigate the effects of physical activity (PA) during pregnancy on maternal blood lipid and hemoglobin A1c (HbA1c) concentrations. We hypothesized that higher PA was associated with improved lipid profile and glycemic control.

METHODS

In a secondary analysis of a randomized controlled trial, we included 216 pregnant women before week 15 + 0 and tested the effects of two different PA interventions throughout pregnancy compared to standard care on maternal blood lipid and HbA1c concentrations. Additionally, we investigated the effect of PA per se measured by an activity tracker. Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglyceride, and HbA1c concentrations were measured at week ≤15 + 0, 28+0-6, 34+0-6, and at delivery (week 32 + 1 to 42 + 0). Effects of the interventions and PA per se were tested using linear mixed effects models and linear regression analyses, respectively.

RESULTS

No effects of the PA interventions were detected on maternal lipids or HbA1c during pregnancy. In PA per se analyses, more minutes per week of moderate-to-vigorous intensity PA were associated with less increase in TC (-1.3E-04, P = .020) and LDL-C (-8.5E-05, P = .035) as pregnancy progresses. More active kilocalories were associated with less increase in TC (-5.5E-05, P < .001), HDL-C (-9.5E-06, P = .024), and LDL-C (-3.2E-05, P = .005).

CONCLUSION

Whilst there were no effects of offering PA interventions, higher PA was associated with reduced increases in TC, HDL-C, and LDL-C as pregnancy progressed.

Determinants of insulin therapy among women with gestational diabetes mellitus: A cross-sectional study

Background

Gestational diabetes mellitus (GDM) is a common complication in pregnancy that occurs during the second half of pregnancy. In the majority of patients, medical nutritional therapy (MNT) alone is sufficient to achieve the glycemic goal.

Aim

To evaluate the clinical and biochemical factors that predict the need for insulin therapy in women with GDM.

Materials and Methods

Between March 2020 and November 2021, an analytic cross-sectional study was conducted on 127 women diagnosed with GDM at their final antenatal visit. Multivariate logistic regression was used to determine the variables associated with the likelihood of insulin requirement in patients with GDM.

Results

To achieve glycemic control, 56.7% of the study population required insulin treatment. Fasting glucose, pre-conceptional body mass index (BMI), parity, and third-trimester glycated hemoglobin levels were all higher in the insulin-treated group (P = 0.00, 0.01, 0.01, and 0.02), respectively. Fasting glucose level is the main determinant of insulin use in patients with GDM (odds ratio [OR]: 1.110; 95% confidence interval [CI]: 1.001-1.191; P = 0.004).

Conclusions

Fasting glucose level is the most important predictor of the need for insulin therapy.

Physical Activity, Body Composition, and Cardiometabolic Health during Pregnancy: A Compositional Data Approach

PURPOSE

The aim of this study was to examine the cross-sectional and longitudinal associations of 24-h movement behaviors (sleep, sedentary behavior (SB), light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA)) with body composition and cardiometabolic health in i) early and ii) late pregnancy (gestational weeks 14 and 37).

METHODS

This observational study utilized cross-sectional ( n = 273) and longitudinal data ( n = 242) from the HealthyMoms trial. Time spent in movement behaviors over seven consecutive 24-h periods (ActiGraph wGT3x-BT accelerometer), body composition (Bod Pod), and cardiometabolic health indicators (glucose levels, homeostatic model for insulin resistance (HOMA-IR), systolic and diastolic blood pressure, metabolic syndrome (MetS) score) were measured in early and late pregnancy.

RESULTS

In early pregnancy, reallocating time to MVPA from LPA, SB, and sleep was associated with lower MetS score (adjusted γ = -0.343, P = 0.002). Correspondingly, reallocating time to LPA from SB and sleep in early pregnancy was associated with lower body weight (adjusted γ = -5.959, P = 0.047) and HOMA-IR (adjusted γ = -0.557, P = 0.031) at the same time point. Furthermore, reallocating time to LPA from SB and sleep in early pregnancy was associated with lower fat mass index (adjusted γ = -0.668, P = 0.028), glucose levels (adjusted γ = -0.315, P = 0.006), HOMA-IR (adjusted γ = -0.779, P = 0.004), and MetS score (adjusted γ = -0.470, P = 0.027) in late pregnancy. The changes in behaviors throughout pregnancy were not associated with body weight, body composition, and MetS score in late pregnancy.

CONCLUSIONS

Our results demonstrated that increasing LPA or MVPA while reducing SB and sleep was associated with lower weight and more favorable cardiometabolic health in early pregnancy. In contrast, LPA in early pregnancy seems to be a stimulus of enough intensity to improve body composition and cardiometabolic health indicators in late pregnancy.

Physical Activity during Pregnancy: Comparisons between Objective Measures and Self-Reports in Relation to Blood Glucose Levels

Objective: to quantify pregnant women’s physical activity during pregnancy using wearable accelerometers and a self-reported scale and to examine the variation in these two physical activity measures in relation to fasting plasma glucose (FPG) levels and presence of gestational diabetes mellitus (GDM). Methods: this prospective observational study included 197 pregnant women from one of the largest regional hospitals in South China. Women with singleton pregnancy, absence of pre-existing comorbidities and pre-specified contraindications, wore an accelerometer on their waist for 7 consecutive days to objectively record their physical activity, followed by completing a past-7-day physical activity questionnaire, three times, respectively, in three trimesters. GDM was determined by 2-h 75 g oral glucose tolerance test (OGTT) in 24–28th week’s gestation and FPG was obtained in both 1st and 2nd trimesters following standard practice. Results: pregnant women engaged highest levels of various physical activity types in 2nd trimester, except accelerometer-based moderate-to-vigorous physical activity which gradually decreased in pregnancy. Pregnant women were more likely to walk in 3rd trimester. The relationship between objective total physical activity and self-reported total physical activity was non-linear. Increased trend of FPG from 1st trimester to 2nd trimester disappeared when adjusting for accelerometer-based light physical activity and attenuated when including walking. Self-reported moderate physical activity was surprisingly positively associated with GDM. Conclusions: different patterns in physical activity between objective measure and self-report in relation to gestational glucose levels were observed. Short-term increase in moderate physical activity prior to OGTT may not be necessary for reducing presence of GDM. Future glucose management for pregnant women may be targeted at lower intensity physical activity.

Leisure-time physical activity in Amazonian pregnant women and offspring birth weight: A prospective cohort study

Compelling evidence supports the current international recommendation of at least 150 min/week of leisure-time physical activity (LTPA) during pregnancy. However, the potential relationship between LTPA and birth weight (BW) remains unclear in low- and middle-income countries. The purpose of this study was to examine the association between LTPA during pregnancy and offspring BW in an Amazonian population. Prospective cohort study was carried-out with 500 pregnant women and their offspring followed-up in the MINA-Brazil study, which was conducted in Cruzeiro do Sul, Western Brazilian Amazon. LTPA was assessed in the second (mean 19.6, SD 2.4 weeks) and third (mean 27.8, SD 1.6 weeks) gestational trimesters by a standardised interview and categorised according to the recommended cut-off of at least 150 min/week. We calculated offspring BW z-scores by sex and gestational age. We then explored the effect of LTPA during pregnancy on offspring BW, the association between LTPA and small-for-gestational-age (SGA) or large-for-gestational-age (LGA) births, and the mediating role of excessive and insufficient gestational weight gain (GWG). At least 150 min/week of LTPA during the third gestational trimester was associated with an offspring BW decrease of -0.35 z-score (95% CI: -0.65, -0.05) or -147.9 grams (95% CI: -260.9, -14.8), without increasing the frequency of SGA foetuses either in the second or third gestational trimester (p > 0.05). Excessive GWG mediated the effect of LTPA on the offspring BW (indirect effect = -0.05 z-score [95% CI: -0.10, -0.00] or -34.7 grams (95% CI: -66.1, -3.3]). This mediation effect was not observed for insufficient GWG. LTPA in the third, but not in the second, trimester of pregnancy was inversely associated with offspring BW without increasing the frequency of SGA, an effect that was partly mediated by excessive GWG.

Postprandial interval walking-effect on blood glucose in pregnant women with gestational diabetes

BACKGROUND

During pregnancy, postprandial hyperglycemia may increase the risk of complications such as fetal macrosomia. However, evidence on beneficial effects of physical activity on postprandial hyperglycemia is sparse.

OBJECTIVE

This study aimed to investigate the effect of 20 minutes of postprandial interval walking on glycemic control and glycemic variability in pregnant women diagnosed as having gestational diabetes mellitus.

STUDY DESIGN

A crossover controlled trial including 14 pregnant women (gestational age 31.8±1.3 weeks) diagnosed as having gestational diabetes mellitus (75 g oral glucose load with 2-hour venous plasma glucose of ≥9.0 mmol/L) was conducted. Participants completed a 4-day intervention period and a 4-day control period with 3 days in between. In each study period, participants received a fixed and identical diet. In the intervention period, participants engaged in 20 minutes of postprandial interval walking after breakfast, lunch, and dinner. Interval walking comprised alternating 3 minutes of slow and fast intervals. Interstitial glucose concentrations were determined during both study periods with a continuous glucose monitor. The mixed effects model was used to compare differences between exercise and no exercise.

RESULTS

Of note, 20 minutes of postprandial interval walking significantly reduced glycemic control during daytime hours relative to the control period (4-day mean glucose, 5.31 [5.04-5.59] vs 5.53 [5.25-5.81] mmol/L [95.6 (90.7-100.6) vs 99.5 (94.5-104.6) mg/dL]; P<.05). On each individual trial day, interval walking significantly reduced glycemic control during daytime hours on day 1 (mean glucose, 5.19 [4.92-5.47] vs 5.55 [5.27-5.83] mmol/L [93.4 (88.6-98.5) vs 99.9 (94.9-104.9) mg/dL]; P=.00), day 2 (mean glucose, 5.32 [5.05-5.60] vs 5.57 [5.29-5.84] mmol/L [95.8 (90.9-100.8) vs 100.3 (95.2-105.1) mg/dL]; P=.00), and day 3 (mean glucose, 5.27 [5.00-5.54] vs 5.46 [5.19-5.74] mmol/L [94.9 (90.0-99.7) vs 98.3 (93.4-103.3) mg/dL]; P=.00), but not on day 4.

CONCLUSION

A total of 20 minutes of postprandial interval walking seems to be an effective way to control postprandial glucose excursions in women with gestational diabetes mellitus.

Markers of branched-chain amino acid catabolism are not affected by exercise training in pregnant women with obesity

Despite the role of branched-chain amino acids (BCAAs) in physiological processes such as nutrient signaling and protein synthesis, there is ongoing debate about the link between circulating BCAAs and insulin resistance (IR) in various populations. In healthy women, IR mildly increases during pregnancy, whereas both BCAAs and markers of BCAA catabolism decrease, indicating that fetal growth is being prioritized. Exercise reduces IR in nonpregnant adults, but less is known about the effect of exercise during pregnancy in women with obesity on IR and BCAA breakdown. The aim of this study was to determine the effect of a moderate-intensity exercise intervention during pregnancy on maternal circulating BCAAs and markers of BCAA catabolism [short-chain acylcarnitines (ACs)], and their associations with IR. Healthy obese [n = 80, means ± SD; body mass index (BMI): 36.9 ± 5.7 kg/m²] pregnant women were randomized into an exercise (n = 40, aerobic/resistance 3×/wk, ∼13th gestation week until birth) or a nonexercise control (n = 40) group. Blood was collected at 12.2 ± 0.5 and 36.0 ± 0.4 gestation weeks and analyzed for BCAA-derived acylcarnitine concentrations as markers of BCAA breakdown toward oxidative pathways, and glucose and insulin concentrations [updated homeostatic model assessment of IR (HOMA2-IR)]. After adjusting for HOMA2-IR, there were no interaction effects of group by time. In addition, there was a main positive effect of time on HOMA2-IR (12 wk: 2.3 ± 0.2, 36 wk: 3.0 ± 0.2, P = 0.003). A moderate-intensity exercise intervention during pregnancy in women with obesity was not associated with changes in BCAA-derived ACs versus standard of care. The decrease in BCAA-derived ACs throughout gestation could not be explained by IR.NEW & NOTEWORTHY This research showed an increase in insulin resistance (IR) and decrease in branched-chain amino acid catabolism throughout gestation in women with obesity, and addition of a moderate exercise intervention (known to attenuate IR in nonpregnant populations) did not alter these shifts. Findings provide support for metabolic safety of exercise during pregnancy.

Objectively measured sedentary time and physical activity levels in Spanish pregnant women. Factors affecting the compliance with physical activity guidelines

The aims of this cross-sectional study were to describe objectively measured sedentary time (ST) and physical activity (PA) levels in Spanish pregnant women, to analyze the degree of compliance with PA guidelines during the early second trimester of pregnancy and to explore sociodemographic and clinical factors associated with meeting these PA guidelines. One hundred and thirty-four Caucasian pregnant women were recruited between October 2015 and October 2017 to participate in this study. Triaxial accelerometers were used to analyze ST andPA levels for seven consecutive valid days. Womenspent512 ± 92.1 minutes daily in sedentary behaviors, and 85 ± 108.2 minutes in moderate-to-vigorous physical activity (MVPA) in bouts of at least 10 minutes. They walked on average 7436 ± 2410steps per day. Only 22% of the study sample complied with the PA guidelines. Having an University degree was related with threefold higher odds of compliance with the PA guidelines (95% confidence interval: 0.096-0.913, p < .05). Binary logistic regressions showed that being primiparous was associated with fivefold higher odds of compliance with the PA guidelines (95% confidence interval 1.658-18.039, respectively, p < .01). Maternal age, BMI, marital status, working status, and previous miscarriages were not associated with compliance with PA guidelines. Pregnant women spent more than a third of the day in sedentary behaviors and the compliance with PA guidelines was less than desirable. Finally, not having an university degree or having children could be factors related to lower odds of compliance with these guidelines, and therefore require special attention from healthcare professionals.

Maternal prepregnancy body mass index and physical activity during pregnancy assessed by accelerometer

BACKGROUND

Maternal prepregnancy overweight and obesity increase the risk of adverse pregnancy outcomes, whereas physical activity during pregnancy has a beneficial effect on both the mother and the fetus. Limited data are available on how maternal prepregnancy overweight and obesity affect physical activity during pregnancy.

OBJECTIVE

The purpose of this study was to describe the association between prepregnancy body mass index and physical activity during pregnancy.

STUDY DESIGN

An observational prospective cohort study of 400 singleton pregnant women who were attending routine antenatal care at Aarhus University Hospital, Denmark (2010-2015), was conducted. Physical activity was assessed by an accelerometer (SenseWear Armband) for 7 days for each trimester. Participants were stratified in 3 different groups of prepregnancy body mass index: normal weight (body mass index <25 kg/m²), overweight (body mass index 25-29.9 kg/m²), and obese (body mass index ≥30 kg/m²). Physical activity was measured as the number of steps per day, metabolic equivalent of task per day, time in moderate- to vigorous-intensity physical activity (>3 metabolic equivalent of task), and time in vigorous-intensity physical activity (>6 metabolic equivalent of task). Linear regression and multilevel mixed-effects models were used to explore the association between prepregnancy body mass index and physical activity variables during pregnancy.

RESULTS

We found an inverse linear relationship between prepregnancy body mass index and both mean number of steps per day and mean metabolic equivalent of task per day (P<.001). At baseline, women with normal weight walked a median of 1214 steps per day (95% confidence interval, 576-1852) more than women who were obese (P<.05), and women who were overweight walked a median of 948 steps per day (95% confidence interval, 218-1677) more than women who were obese (P<.05). Independent of prepregnancy body mass index, all variables of physical activity decreased over the course of pregnancy (P<.05), with the greatest decrease in the third trimester.

CONCLUSION

Maternal physical activity measured by an accelerometer decreased across pregnancy independent of maternal body mass index status and was inversely associated with prepregnancy body mass index. Thus, being overweight or obese before pregnancy increased the risk of sedentary behavior during pregnancy.

Physical Activity Patterns among 9000 Pregnant Women in Poland: A Cross-Sectional Study

The aim was to analyze the knowledge and experience of women regarding physical activity during their latest pregnancy. An anonymous questionnaire was completed electronically, in 2018, by 9345 women who gave birth at least once, with 52% of the women having performed exercises during pregnancy. Physically non-active respondents suffered from gestational hypertension (9.2% vs. 6.7%; p < 0.01) and gave birth prematurely (9% vs. 7%; p < 0.01) to newborns with a low birth weight significantly more often (6% vs. 3.6%; p < 0.001). Physically active women delivered vaginally more often (61% vs. 55%; p < 0.001) and were more likely to have a spontaneous onset of the delivery as compared with non-active women (73.8% vs. 70.7% p = 0.001). The women who were informed by gynaecologist about the beneficial influence of physical activity during pregnancy exercised significantly more often (67% vs. 44% p < 0.001). In addition, 13% of the women felt discrimination due to their physical activity during a pregnancy, 22% of respondents' physical activity was not accepted by their environment, and 39.1% of the women were told by others to stop physical exercise because it was bad for the baby's health. Physical activity during pregnancy is associated with improved fitness, decreased pregnancy ailments occurrence, and therefore influences the course of pregnancy and delivery in a positive way.

The association of human milk oligosaccharides with glucose metabolism in overweight and obese pregnant women

BACKGROUND

Human milk oligosaccharides (HMOs) were recently found in serum of normal-weight pregnant women, with concentrations increasing from early to mid- and late pregnancy. Whether HMOs have effects on maternal metabolism is unknown.

OBJECTIVES

We aimed to study the presence and changes in HMOs throughout pregnancy and assess associations with maternal glucose metabolism throughout pregnancy.

METHODS

The study was a prospective longitudinal cohort study including 87 overweight or obese women. Blood samples were taken at 15, 24, and 32 wk of pregnancy. In serum, 4 HMOs [2'-fucosyllactose (2'FL), lactodifucotetraose (LDFT), 3'-sialyllactose (3'SL), and 3'-sialyllactosamine (3'SLN)] were measured. In linear regression models, the associations between HMOs and (changes in) maternal metabolic parameters were assessed.

RESULTS

All 4 HMOs showed a significant increase from 15 to 32 weeks of gestation. 3'SL and 3'SLN, but not 2'FL or LDFT, at 15 wk were positively associated with (changes in) fasting glucose at 24 and 32 wk. LDFT was positively associated with (changes in) insulin and HOMA-index at 24 but not 32 wk. A model to predict the development of gestational diabetes mellitus (GDM) that included fasting glucose, prepregnancy BMI, gestational weight gain, age, parity, smoking, and history of macrosomia resulted in an area under the curve (AUC) of 0.81 (95% CI: 0.70, 0.92). Adding 3'SL to this model increased the AUC to 0.91 (95% CI: 0.84, 0.97).

CONCLUSIONS

The sialylated HMOs 3'SL and 3'SLN were associated with fasting glucose; LDFT was associated with fasting insulin and HOMA-index. Furthermore, 3'SL was more predictive of future GDM diagnoses than was fasting glucose in early pregnancy. Causal relations are unclear and need further investigation.

Prevalence of gestational diabetes mellitus and associated factors among women attending antenatal care at Gondar town public health facilities, Northwest Ethiopia

Background

Globally, Gestational Diabetes Mellitus (GDM) is rising, but it is a neglected health threat to mothers and their children in low resource countries. Although, GDM is known in Ethiopia, information regarding it remains scarce by recent diagnostic criteria. Therefore, this study aimed to determine the prevalence of GDM and associated factors among women attending antenatal care at Gondar town public health facilities, Northwest Ethiopia.

Methods

A cross-sectional study was conducted among 1027 pregnant women selected by the systematic random sampling technique. The universal one-step screening and diagnostic strategy was done using a two-hour 75 g oral glucose tolerance test. GDM was diagnosed using updated diagnostic criteria (2017 American Diabetes Association (ADA) or 2013 World Health Organization (WHO) or modified International Association of the Diabetes and Pregnancy Study Groups diagnostic criteria (IADPSG)). Binary logistic regression model was used to identify factors associated with GDM.

Results

Of the total 1027 pregnant women, 12.8% (95% CI: 10.8–14.8) were diagnosed with GDM. Overweight and/or obesity (MUAC ≥28 cm) (AOR = 2.25, 95% CI: 1.18–4.26), previous history of GDM (AOR = 5.82, 95% CI: 2.57–13.18), family history of diabetes (AOR = 4.03, 95% CI: 1.57–10.35), low physical activity (AOR = 3.36, 95% CI: 1.60–7.04), inadequate dietary diversity (AOR = 1.9, 95% CI: 1.02–3.53), and antenatal depression (AOR = 4.12, 95% CI: 1.85–9.20) were significantly associated with GDM.

Conclusions

The prevalence of GDM among women attending antenatal care at Gondar town public health facilities was high. Previous history of GDM, antenatal depression, family history of diabetes, low physical activity, overweight and/or obesity and inadequate dietary diversity were significantly associated with GDM. Routine screening of pregnant women and healthy lifestyle are strongly recommended.

Exercise in Pregnant Women with Diabetes

PURPOSE OF REVIEW

Diabetes affects an increasing number of pregnancies. Regular exercise is recommended for pregnant women without diabetes, but whether exercise during pregnancy also benefits women with gestational diabetes (GDM) or preexisting (type 1 or type 2) diabetes or if these women have any specific risks is unclear.

RECENT FINDINGS

Recent evidence suggests that low- to moderate-intensity exercise improves blood glucose and may delay insulin initiation for women with GDM. Exercise is also safe, with no reports of increased maternal or neonatal complications. Few studies evaluated exercise as adjunct therapy for pregnant women with preexisting diabetes, precluding a thorough assessment in this population. Low- to moderate-intensity exercise during pregnancy safely improves glycemic control among women with GDM. More studies are needed to evaluate the impact of exercise in pregnant women with preexisting diabetes. Whether a specific type, volume, or timing of activity is most effective is not known.

Prepregnancy Fat Free Mass and Associations to Glucose Metabolism Before and During Pregnancy

OBJECTIVE

Our aim was to quantify the individual contribution of prepregnancy (PP) fat-free mass (FFM), expressed as [PP-FFM index (PP-FFMI) = FFM (kg)/height (m2)], on markers of glucose homeostasis before and during pregnancy.

METHODS

Body composition was assessed in 43 women before pregnancy using air-displacement plethysmography. Blood was drawn at PP and gestational weeks ∼8 and 30. Relationships between body composition (independent) variables and glucose homeostasis (dependent) variables were assessed using adjusted correlations and simple and multiple linear regression analyses.

RESULTS

PP-FFMI was the strongest predictor of plasma insulin concentration [squared partial correlation (Pr2) = 17, P = 0.007] and homeostasis model assessment of insulin resistance (HOMA2-IR) (Pr2 = 16, P = 0.010). At gestation week 30, PP-FFMI and gestational weight gain (GWG) were the strongest predictors of insulin concentration (PP-FFMI: Pr2 = 20, P = 0.010; GWG: Pr2 = 12, P = 0.052) and HOMA2-IR (PP-FFMI: Pr2 = 19, P = 0.012; GWG: Pr2 = 13, P = 0.045). After accounting for PP fat mass index (PP-FMI), PP-FFMI and GWG were independently associated with first-phase insulin response (PP-FFMI: Pr2 = 20, P = 0.009; GWG: Pr2 = 15, P = 0.025) and second-phase insulin response (PP-FFMI: Pr2 = 19, P = 0.011; GWG: Pr2 = 17, P = 0.016). PP-FMI was the strongest predictor of an oral glucose tolerance test‒derived estimated metabolic clearance rate of glucose (PP-FMI: Pr2 = 14, P = 0.037) and estimated insulin sensitivity index (PP-FMI: Pr2 = 13, P = 0.047).

CONCLUSIONS

PP-FFMI was a predictor of markers of glucose homeostasis before and during pregnancy. Studies assessing the effect of skeletal muscle quality on metabolic regulation during pregnancy are warranted.

Associations between maternal physical activity in early and late pregnancy and offspring birth size: remote federated individual level meta-analysis from eight cohort studies

OBJECTIVE

Evidence on the impact of leisure time physical activity (LTPA) in pregnancy on birth size is inconsistent. We aimed to examine the association between LTPA during early and late pregnancy and newborn anthropometric outcomes.

DESIGN

Individual level meta-analysis, which reduces heterogeneity across studies.

SETTING

A consortium of eight population-based studies (seven European and one US) comprising 72 694 participants.

METHODS

Generalised linear models with consistent inclusion of confounders (gestational age, sex, parity, maternal age, education, ethnicity, BMI, smoking, and alcohol intake) were used to test associations between self-reported LTPA at either early (8-18 weeks gestation) or late pregnancy (30+ weeks) and the outcomes. Results were pooled using random effects meta-analyses.

MAIN OUTCOME MEASURES

Birth weight, large-for-gestational age (LGA), macrosomia, small-for-gestational age (SGA), % body fat, and ponderal index at birth.

RESULTS

Late, but not early, gestation maternal moderate to vigorous physical activity (MVPA), vigorous activity, and LTPA energy expenditure were modestly inversely associated with BW, LGA, macrosomia, and ponderal index, without heterogeneity (all: I2  = 0%). For each extra hour/week of MVPA, RR for LGA and macrosomia were 0.97 (95% CI: 0.96, 0.98) and 0.96 (95% CI: 0.94, 0.98), respectively. Associations were only modestly reduced after additional adjustments for maternal BMI and gestational diabetes. No measure of LTPA was associated with risk for SGA.

CONCLUSIONS

Physical activity in late, but not early, pregnancy is consistently associated with modestly lower risk of LGA and macrosomia, but not SGA.

TWEETABLE ABSTRACT

In an individual participant meta-analysis, late pregnancy moderate to vigorous physical activity modestly reduced birth size outcomes.

Determinants of Maternal Insulin Resistance during Pregnancy: An Updated Overview

Insulin resistance changes over time during pregnancy, and in the last half of the pregnancy, insulin resistance increases considerably and can become severe, especially in women with gestational diabetes and type 2 diabetes. Numerous factors such as placental hormones, obesity, inactivity, an unhealthy diet, and genetic and epigenetic contributions influence insulin resistance in pregnancy, but the causal mechanisms are complex and still not completely elucidated. In this review, we strive to give an overview of the many components that have been ascribed to contribute to the insulin resistance in pregnancy. Knowledge about the causes and consequences of insulin resistance is of extreme importance in order to establish the best possible treatment during pregnancy as severe insulin resistance can result in metabolic dysfunction in both mother and offspring on a short as well as long-term basis.

Angiopoietin-like protein 4 (ANGPTL4) is related to gestational weight gain in pregnant women with obesity

Angiopoietin-like protein 4 (ANGPTL4) is a circulating protein involved in the regulation of adipose tissue metabolism. However, its role in obesity and pregnancy is unknown. To evaluate the relationship between gestational weight gain (GWG) and circulating concentrations of ANGPTL4 in pregnant women with overweight and obesity, weight gain and fasting maternal blood samples of thirty-one pregnant women was drawn at 15, 24 and 32 weeks of gestation. ANGPTL4 concentrations continuously rose throughout gestation, whereas VEGF and leptin did not show the same trend. NEFA and glycerol concentrations remained stable during pregnancy. In contrast, total concentrations of saturated, monounsaturated and n-6 fatty acids, but not n-3 fatty acids, increased with pregnancy. In multiple regression analysis, the increase in plasma ANGPTL4 and decrease in linoleic acid concentrations were the most significant predictors of GWG, although only ANGPTL4 was significantly associated with the weight gain from early pregnancy (area under the ROC curve was 0.80 p < 0.01(95% CI 0.61-0.99)). In conclusion, in pregnant women with overweight and obesity, an increase in plasma ANGPTL4 concentrations throughout pregnancy is positively associated with GWG and could be used as an early marker of increased susceptibility to excess gestational weight gain.

Prepregnancy Fitness and Risk of Gestational Diabetes: A Longitudinal Analysis

PURPOSE

This study aimed to assess the associations of prepregnancy cardiorespiratory fitness, moderate- to vigorous-intensity physical activity (MVPA), and time spent watching television with subsequent development of gestational diabetes mellitus (GDM).

METHODS

Participants were 1333 women enrolled in the Coronary Artery Risk Development in Young Adults study who did not have diabetes either at baseline (1985-86) or before births occurring after baseline. Baseline fitness was estimated using a graded symptom-limited maximal exercise treadmill test and expressed in MET units. Baseline MVPA (exercise units per day) was measured using the Coronary Artery Risk Development in Young Adults physical activity history questionnaire, and television viewing (h·d) was assessed by self-report in 1990-1991. Logistic regression analysis was used to derive odds ratios and 95% confidence intervals, adjusting for time from baseline to delivery and baseline study center, age, race, education, parity, family history of diabetes, smoking, alcohol, saturated fat intake, waist circumference, homeostasis model assessment of insulin resistance, and HDL cholesterol.

RESULTS

Over 25 yr of follow-up, 164 women developed GDM. The odds of developing GDM were 21% lower for each 1 SD increment in baseline level of fitness (2.3 METs, odds ratio = 0.79, 95% confidence interval = 0.65-0.96). Prepregnancy MVPA and television viewing were not statistically associated with the development of GDM.

CONCLUSION

Study findings indicate that objectively assessed prepregnancy fitness, but not self-reported MVPA or television time, is associated with GDM. Clinicians should counsel women on the benefits of improving fitness in the preconception period, particularly among women at greater risk for GDM.

Origins in the Womb: Potential Role of the Physical Therapist in Modulating the Deleterious Effects of Obesity on Maternal and Offspring Health Through Movement Promotion and Prescription During Pregnancy

Maternal obesity and associated metabolic disease contribute to adverse outcomes in women and their offspring, and many of these outcomes have significant acute and chronic implications for both mother and neonate. Targeted movement (ie, physical activity or exercise training) during pregnancy has been shown to be safe and effective for improving many of these outcomes in women at a healthy weight and women who are obese. However, movement prescription and advice during pregnancy are often not addressed by health care providers; this situation creates a unique opportunity for physical therapists to use their expertise in movement with patients who are pregnant. The objective of this article is to briefly review the adverse maternal and neonatal outcomes associated with maternal obesity, the benefits of intentional maternal movement during pregnancy for women who are obese, the evidence-based guidelines for prescribing intentional movement during pregnancy for women who are obese, and the potential for physical therapists to become the driving force behind a necessary increase in movement levels in women who are pregnant. Physical therapists can play a significant role in encouraging movement in women who are healthy and women who have metabolic challenges during pregnancy and thus assist in combating the vicious cycle of obesity by improving maternal and offspring health.

Physical activity and the risk for gestational diabetes mellitus amongst pregnant women living in Soweto: a study protocol

Background

Over the past decade the prevalence of gestational diabetes mellitus (GDM) has increased rapidly in both developed and developing countries and has become a growing health concern worldwide. A recent systematic review highlighted the paucity of data available on the prevalence and potential burden of GDM in Africa, which was emphasised by the fact that only 11 % of African countries were represented in the review. In South Africa, the prevalence of GDM remains unknown, although one would estimate it to be high due to urbanisation and the growing obesity epidemic. In addition, the association between physical activity (PA), sedentary behaviour (SB) and GDM is not well understood in this population. The aim of the proposed research is to determine whether there is an association between physical activity, sedentary behaviour and risk for GDM in pregnant black women living in urban Soweto in South Africa.

Methods/Design

This prospective cohort study of 80 participants will include pregnant women from Soweto enrolled into the Soweto First 1000 Days Study (S1000) at the MRC/Wits Departmental Pathways for Health Research Unit (DPHRU) based at the Chris Hani Baragwanath Academic Hospital in Soweto, South Africa. Women will be enrolled into the S1000 Study at <14 weeks gestation, and baseline demographic and anthropometric measures will be taken at 14–18 weeks gestation (visit 1). In addition, participants will complete the Global Physical Activity Questionnaire (GPAQ) to measure self-reported physical activity and will be given an ActiGraph accelerometer to wear for seven days to measure habitual physical activity at 14–18 weeks gestation (visit 1), and at 28–33 weeks gestation (visit 3). At visit 2 (24–28 weeks gestation) an oral glucose tolerance test (OGTT) will be conducted.

Discussion

Physical activity during pregnancy has been associated with minimum risk to a pregnancy and may play a role in improving glucose metabolism and therefore decreasing risk for GDM. This is particularly pertinent to assess amongst black South African women who are a potentially high risk population due to the high prevalence of obesity and type 2 diabetes (T2D). The findings of the study will assist in developing targeted interventions as well as feasible healthcare strategies.

Antenatal physical activity: a qualitative study exploring women's experiences and the acceptability of antenatal walking groups

BACKGROUND

Regular physical activity (PA) can be beneficial to pregnant women, however, many women do not adhere to current PA guidelines during the antenatal period. Patient and public involvement is essential when designing antenatal PA interventions in order to uncover the reasons for non-adherence and non-engagement with the behaviour, as well as determining what type of intervention would be acceptable. The aim of this research was to explore women's experiences of PA during a recent pregnancy, understand the barriers and determinants of antenatal PA and explore the acceptability of antenatal walking groups for further development.

METHODS

Seven focus groups were undertaken with women who had given birth within the past five years. Focus groups were transcribed and analysed using a grounded theory approach. Relevant and related behaviour change techniques (BCTs), which could be applied to future interventions, were identified using the BCT taxonomy.

RESULTS

Women's opinions and experiences of PA during pregnancy were categorised into biological/physical (including tiredness and morning sickness), psychological (fear of harm to baby and self-confidence) and social/environmental issues (including access to facilities). Although antenatal walking groups did not appear popular, women identified some factors which could encourage attendance (e.g. childcare provision) and some which could discourage attendance (e.g. walking being boring). It was clear that the personality of the walk leader would be extremely important in encouraging women to join a walking group and keep attending. Behaviour change technique categories identified as potential intervention components included social support and comparison of outcomes (e.g. considering pros and cons of behaviour).

CONCLUSIONS

Women's experiences and views provided a range of considerations for future intervention development, including provision of childcare, involvement of a fun and engaging leader and a range of activities rather than just walking. These experiences and views relate closely to the Health Action Process Model which, along with BCTs, could be used to develop future interventions. The findings of this study emphasise the importance of involving the target population in intervention development and present the theoretical foundation for building an antenatal PA intervention to encourage women to be physically active throughout their pregnancies.

Trajectories of objectively-measured physical activity and sedentary time over the course of pregnancy in women self-identified as inactive

There is a need for investigations that document the daily course of pregnancy-related changes in PA and sedentary behavior. The purpose of this study was to describe the trajectory of PA and sedentary behavior and whether they differ among weight status in pregnant women self-identified as inactive. Eighty inactive pregnant women (8-16 weeks) were recruited from a nationwide text-message intervention. PA was measured using a Fitbit. Chi-square analyses and t-tests were used to analyze univariate demographic and PA variables. Mixed model-repeated measures ANOVA was used to analyze trajectory changes in daily PA and sedentary behavior. Light activity (beta [SE] = 2.79 [0.30], p < .001), active time (b [SE] = 1.62 [0.16], p < .001), and steps (b [SE] = 112.21 [10.66], p < .001) increased during the second trimester followed by a precipitous decline during the third trimester. Sedentary behavior followed an opposite pattern (b = - 9.88 [1.07], p < .001). Overweight and obese women took significantly fewer steps/day (b [SE] = - 742.37 [362.57], p < .05 and - 855.94 [381.25], p < .05, respectively) than normal weight women, and obese women had less "active" minutes/day (~> 3.0 metabolic equivalents; b [SE] = - 12.99 [5.89], p < .05) than normal weight women (P's < 0.05). Women who self-identify as inactive, become more sedentary and less physically active as pregnancy progresses. This study was among the first to describe the trajectory of daily PA and sedentary behavior throughout pregnancy. This study may help inform health care provider and patient communication related to PA, sedentary behavior, and the time in which to communicate about these behaviors.

Application of objective physical activity measurement in an antenatal physical activity consultation intervention: a randomised controlled trial

BACKGROUND

Physical Activity (PA) during pregnancy has many health benefits, however, inactivity in this population is common and PA often declines with increasing gestation. PA consultations have been useful in promoting PA in the general population, however their use for addressing PA in pregnancy is unknown. This study aimed to examine if a theory-based intervention using PA consultations would reduce the magnitude of decline in objectively measured PA between the first and third trimesters of pregnancy.

METHODS

A RCT was carried out in an urban maternity unit in Northern Ireland between September 2012 and June 2013. 109 low-risk, primigravida pregnant women were randomised to a control (n = 54) or intervention group (n = 55). Intervention participants received three face-to-face individual PA consultations. Daily PA was measured in each trimester using seven day accelerometry. The study was approved by a NHS trust (12/NI/0036). PA data in counts per minute (CPM) were categorised into intensity using Freedson cut points and mean minutes of PA were compared between groups using repeated measures ANOVA with a sub-analysis stratifying participants per PA level in trimester one.

RESULTS

Intention to treat analysis was performed on data from 97 participants. Time in moderate, vigorous and moderate-vigorous intensity PA (MVPA) significantly declined between trimesters one and three in both groups (P < 0.001). There were no statistically significant differences in PA between groups in any trimester. Women in the intervention group who were less active in trimester one did not demonstrate a significant decline in MVPA throughout pregnancy (in contrast with the decline identified in the more active participants).

CONCLUSIONS

The findings indicate that PA consultations were not effective in reducing the decline of MVPA in throughout pregnancy, however, women who were less active in trimester one and received PA consultations had a lesser decrease in MVPA. It is possible that pregnant women, specifically those who are more active at the start of pregnancy, have differing needs for PA behaviour change and maintenance, requiring more intense interventions than less active women.

TRIAL REGISTRATION

Current Controlled Trials Register ISRCTN61829137.

Exercise in pregnancies complicated by obesity: achieving benefits and overcoming barriers

An increasing number of women are entering pregnancy in an overweight or obese state. Obese women and their offspring are at increased risk of adverse perinatal outcomes, which may be improved by regular moderate-intensity antenatal exercise. Current guidelines recommend that all pregnant women without contraindications engage in ≥30 minutes of moderate-intensity exercise on a daily basis. However, obese women are usually less physically active and tend to further reduce activity levels during pregnancy. This commentary summarizes the potential short- and long-term benefits of antenatal exercise in obese pregnant women, highlights the challenges they face, and discusses means of improving their exercise levels. In addition, we make recommendations on exercise prescription for pregnancies complicated by obesity.

Review of impacts of physical activity on maternal metabolic health during pregnancy

Our purpose was to review relations between physical activity during pregnancy, gestational diabetes, and other maternal metabolic markers (i.e., lipids, tumor necrosis factor alpha (TNFα), interleukin six (IL-6), leptin, and adiponectin). While observational studies indicate a protective effect of physical activity on gestational diabetes, interventions that promote recommended levels of physical activity during pregnancy (i.e., 150+ min/week) have failed to show significant effects. However, interventions have been often underpowered and with low protocol adherence. Maternal lipids, TNFα, IL-6, and leptin all increase and adiponectin decreases with a healthy pregnancy. Although the evidence base is small, preliminary results indicate a beneficial effect of physical activity on lowering triglycerides, TNFα, and leptin levels while increasing muscle-derived IL-6 levels during pregnancy. Future studies are needed to examine relationships among prospectively measured physical activity and metabolic markers throughout pregnancy, as well as theoretically based physical activity interventions to prevent gestational diabetes.

The relationship between moderate-to-vigorous intensity physical activity and insulin resistance, insulin-like growth factor (IGF-1)-system 1, leptin and weight change in healthy women during pregnancy and after delivery

CONTEXT

Childbearing is considered to be a significant risk factor for developing overweight and obesity. Physical activity might influence weight change via hormonal changes.

OBJECTIVE

To test the hypothesis that higher levels of moderate-to-vigorous intensity physical activity (MVPA) are positively associated with maternal insulin sensitivity and reduce IGF-1, IGFBP-3, leptin levels, bodyweight gain/retention and birth weight.

METHODS

In healthy nulliparous women, weight measurements were carried out and blood was collected during pregnancy in the 15th, 25th and 35th week, and after delivery at 6, 26 and 52 weeks. At 15 and 35 weeks of pregnancy and 26 weeks postpartum, MVPA was measured using accelerometers. In linear regression models, the relationship between MVPA below or above the median with metabolic and weight outcomes was assessed, adjusted for maternal BMI, age and smoking.

RESULTS

Moderate-to-vigorous intensity physical activity (MVPA) decreased significantly during pregnancy, but was very low already in early pregnancy. Insulin resistance and leptin levels increased during pregnancy and decreased significantly after delivery (all P < 0·05). After adjustment, insulin, IGFBP-3 and BMI were significantly lower at 15 weeks of pregnancy in women with MVPA above the median compared to those with MVPA below the median. After 15 weeks of pregnancy, no significant associations were observed between hormonal levels and MVPA. MVPA was neither related to weight retention, nor to birth weight.

CONCLUSION

Except in early pregnancy, MPVA was not related to metabolic outcomes. In addition, MVPA during pregnancy was not related to weight retention or birth weight.

Physical activity in overweight and obese pregnant women is associated with higher levels of proinflammatory cytokines and with reduced insulin response through interleukin-6

OBJECTIVE Previously, we reported the positive association of moderate-to-vigorous physical activity (MVPA) with insulin sensitivity in overweight and obese pregnant women. We sought to assess whether these MVPA-induced changes in insulin sensitivity are mediated by changes in interleukin (IL)-6, IL-10, tumor necrosis factor (TNF)-α, and IL-1β. RESEARCH DESIGN AND METHODS A prospective longitudinal study was conducted in 46 overweight and obese women at risk for gestational diabetes mellitus. Objective physical activity measurements and fasting blood samples were taken at 15, 24, and 32 weeks of pregnancy. At 24 and 32 weeks, a 100-g oral glucose test was performed in addition. Cytokines, C-reactive protein, and glucose and insulin levels were measured, and insulin sensitivity and first-phase insulin response were calculated. Relationships between the different parameters were assessed using linear regression models, adjusting for maternal age and BMI. RESULTS All cytokines were elevated in women with higher levels of MVPA at 15 weeks of gestation. Higher IL-6 was related to a lower first-phase insulin response (β -810.5 [95% CI -1,524.5 to -96.5]; P = 0.03). TNF-α and IL-1β had different effects in women with low MVPA (with low IL-6 levels) compared with more active women. CRP was not related to MVPA. CONCLUSIONS The association of MVPA with insulin sensitivity and first-phase insulin response may be (partly) mediated by IL-6, since this cytokine was related to reduced first-phase insulin response. The possible positive effects of the elevated cytokine profile in active obese pregnant women warrant further study.