|Year : 2021 | Volume
| Issue : 3 | Page : 165-172
Effect of daily walking program on glucose level among overweight pregnant women
Rania Mahmoud Abdel Ghani
Department of Maternal and Newborn Health Nursing, Faculty of Nursing, Cairo University-Giza-Egypt; Department of Maternal and Newborn Health Nursing, Faculty of Nursing, Galala University-Egyptian National University-New Galala City-Sokhna-, Egypt
|Date of Submission||15-Jul-2020|
|Date of Decision||23-Mar-2021|
|Date of Acceptance||05-Aug-2020|
|Date of Web Publication||23-Jul-2021|
Rania Mahmoud Abdel Ghani
6 El Manshia Street, Beside Saudi School, Safwa Tawer, Faisal.
Source of Support: None, Conflict of Interest: None
Background: Overweight and obese pregnant women are more than twice at the risk of developing gestational diabetes mellitus in comparison to nonobese women. Objective: The objective of the study was to examine the effect of daily walking program on glucose level among overweight pregnant women. Methods: A quasi-experimental study was conducted in 2019 at Kasr El Aini, Cairo University Maternity Hospitals, at the antenatal outpatient clinic. A purposive sample of 100 primigravida, singleton, overweight, had an uncomplicated pregnancy, at 14 weeks of gestation were recruited in the study. A structured interview scheduled questionnaire, an anthropometric measurement scale, the pregnancy physical activity questionnaire, and a pedometer/step counter were used for data collection. The walking program was an 8-week program with six interviews and emphasized practice walking. The walking program started after the third interview and continued for 8 weeks. All women in the study group were instructed to practice daily walking for 8 weeks. They instructed to walk 30 min (brisk steps) on daily base, started by 15 min and gradually increase the timing of walking up to 30 min for at least 5 days weekly. The hypothesis was tested through student’s t-test and Chi-square test. Results: The intervention group had lower fasting plasma glucose mg/dl levels with mean of 110.80 ± 5.86 versus 114.80 ± 8.07 in the control group and HbA1c with mean of 6.38 ± 0.62 versus 6.60 ± 0.52 in the control group (P ≤ 0.05). Conclusion: Prediabetic, overweight pregnant women who have completed an average of 6,000 steps walking or more per day early in the second trimester may have lower levels of insulin resistance and lower frequency of exposure to gestational diabetes.
Keywords: Daily walking program, glucose level, overweight pregnant women
|How to cite this article:|
Abdel Ghani RM. Effect of daily walking program on glucose level among overweight pregnant women. Nurs Midwifery Stud 2021;10:165-72
| Introduction|| |
Overweight and obesity are the greatest health challenges worldwide, especially throughout the childbearing age. Overweight and obesity are generally recognized as having an effect on the entire pregnancy and as being the major risk factors for perinatal complications, such as gestational diabetes mellitus (GDM), hypertension, fetal development disorders, and cesarean section. Overweight and obese pregnant women are more than twice at the risk of developing GDM in comparison to nonobese women. GDM is of particular concern because of its effects on certain adverse pregnancy outcomes, such as preeclampsia, macrosomia, or cesarean delivery. GDM incidence is as high as 15%–20% of all births and increases with older maternal age, overweight, and obesity by 29.3%. Importantly, women with GDM are likely to become overweight. Physical activity (PA) has been demonstrated to minimize glucose levels, improve insulin sensitivity, and play a critical role in reducing the risk of GDM. It has been shown that moderate-to-vigorous PA and daily walking have beneficial impacts on insulin sensitivity, glucose tolerance, and overall risk reduction for GDM before and during pregnancy., However, there are limited studies investigating the impact of daily walking during pregnancy and few focusing on pregnant women who are overweight. Furthermore, there are conflicting results from the few randomized controlled trials that investigated these topics. A study reported that the exercise program conducted during pregnancy reduced the prevalence of GDM by preserving glucose tolerance. Some studies also concluded that previously sedentary women who began exercising at 12–14 weeks of gestation improved fitness and delivery outcomes, and regular moderate-intensity exercise performed over the second-third trimesters of pregnancy can be used to attenuate important GDM-related adverse outcomes. On contrast, a study concluded that a behavioral intervention addressing diet and PA in women with obesity during pregnancy is not adequate to prevent gestational diabetes or to reduce the incidence of large-for-gestational-age infants. However, Simmons etal. compared the effectiveness of three lifestyle interventions (healthy eating [HE], PA, and both HE and PA [HE+PA]) with usual care in reducing GDM risk. They found that, the combined HE+PA intervention was able to limit gestational weight gain but did not reduce fasting glycemia. Thus, lifestyle changes alone are unlikely to prevent GDM among women with a body mass index (BMI) of ≥29kg/m2. In addition, a study reported that the antenatal lifestyle advice used in their study for women who were overweight or obese did not reduce the risk delivering a baby weighing above the 90th percentile for gestational age and sex or improve maternal pregnancy outcome. Another study also concluded that there are no evidence that offering women a 12-week standard exercise program during the second half of pregnancy prevent gestational diabetes or improve insulin resistance in healthy pregnant women with normal BMI. Therefore, the question remained that can a daily walking program reduce the glucose level among overweight pregnant women.
The aim of the study was to examine the effect of daily walking program on glucose level among overweight pregnant women.
| Methods|| |
Study design and participants
A quasi-experimental study was conducted in 2019 at Kasr El Aini, Cairo University Maternity hospitals, at the outpatient antenatal clinic. The present study is based on the theory of self-regulation which emphasizes the importance of setting goals, planning, and self-monitoring in changing behavior. A purposive sample of one hundred pregnant women who attended the antenatal clinic for routine follow-up, between 18 and 35 years of age, educated (i.e., had at least primary education), primigravida, singleton, overweight (i.e., prepregnancy BMI 25.0 – 29.9kg/m2) had an uncomplicated pregnancy, at 14 weeks of gestation, physically inactive prepregnancy (i.e., did not obtain the proposed level of standard PA, 30 min or progressively essential 5 events per week, prediabetic (i.e., hemoglobin A1c [HbA1c] <5.6 mmol/L, and fasting blood sugar between 80 and 92mg/dL), and with a family history of diabetes were recruited into the study. Those who experienced complication during this pregnancy, who exercised walking fewer than 5 days/week in the current walking program, who skipped two or more follow-ups, and who unable to understand the consequences of participation, were excluded from the study.
Given a confidence level of 95%, a power of 0.80, and based on the proposed intervention effect size of 0.67, the sample size for each group was estimated at 50. Then, the pregnant women with inclusion criteria were consecutively recruited and using random sample table to assign them randomly to an intervention group and a control group, 50 women in each.
Data collection instruments
Data were collected using the following: (1) an structured interview scheduled questionnaire, (2) anthropometric measurements, (3) pregnancy PA questionnaire (PPAQ), and (4) pedometer/step counter.
The interview structured scheduled questionnaire was designed to gather the data as follows: (1) sociodemographic data (i.e., age, education level, and the occupation) and (2) baseline assessment, obstetric history such as parity, last menstrual period, expected date of delivery, and gestational age.
Anthropometric measurements included BMI (to the nearest 0.1kg) and height (to the nearest cm) were measured using a calibrated medical scale and measuring tape, respectively. BMI was calculated as body mass in kilogram over the squared height in meter.
PPAQ is a valid self-administered questionnaire and determines the degree of PA in pregnant women in particular. Women are asked to choose an exemplary classification that approximates the amount of time spent in 32 tasks, including household/care (13 questions), occupational (5 questions), sports/exercise (8 questions), transport (3 questions), and inactivity (3 questions) throughout the current trimester. An open-ended segment at the end of the PPAQ enables the respondent to have feature activities which are no longer identified. The period of time spent in each activity is multiplied by its intensity to meet a calculation attributable to each task of typical weekly energy expenditure (MET-h·week-1). Metabolic equivalent (MET)-minutes is the energy expended while sitting at rest. The MET value of activity and exercise is calculated relative to rest (for example, walking at a pace equivalent to 5 METs for 30 min: 5 METs × 30 min = 150 MET min). MET-h·week represents metabolic equivalent hours/week. Compendium-based MET values are used to measure the other PPAQ activities’ strength. Moderate-intensity physical activities were given an average MET value of 4, although household tasks got an average MET of 3. The MET values of 4.5, 3.5, and 2.8 were allocated to brisk walking, pace walking, and slow walking. Scoring calculation details for duration and intensity described by Chasan-Taber et al.
Pedometer/step counter is a small device that provides the steps/day average as a standard measure for PA assessment. In this analysis, the pedometer model used was the New Lifestyle DIGI-WALKER SW-200 (NLSW-200; Oregon). The NL SW-200 is a small, lightweight pedometer, which comes with a safety clip and measures steps entirely. Steps of the pedometer were represented as mean steps/day and graded as sedentary <5000 steps/day; low active 5000–7499 steps/day; and active >7500 steps/day.
The walking program was an 8-week program with six interviews, the program emphasized walking practice. The first interview was approached when pregnant women were at 14-week gestation, while waiting for routine examination in an outpatient antenatal clinic. Baseline assessment of sociodemographic data, obstetric history, gestational weeks, pre-pregnancy BMI, and the present BMI was taken. The pregnant women were asked to do fasting blood sugar and HbA1c and bring the results within 1 week. The second interview was approached 1 week after the first interview. All pregnant women in both groups were assessed for their physical activities by PPAQ and calculate the MET per week (MET-min/week). The pregnant women in both groups have been handed the pedometer after detailed explanation on its use. They instructed to attach the pedometer to the waistbands of their skirts during waking hours for 7 days. Before bedtime, the pregnant women were asked to log the daily steps and reset the device in the morning. The participants have been informed to remove the pedometer for bathing and sleeping only. The third interview was 1 week after the second one, the average of daily steps were calculated and recorded for each pregnant woman using the pedometers in both groups, and the researcher recorded the steps/day for the previous 7 days (stored in the memory on the device) and compared it with women’s records of daily steps. The walking program started after the third interview and continued for 8 weeks. All women in the intervention group were instructed to practice daily walking for 8 weeks. They instructed to walk 30 min (brisk steps) on daily base and started by 15 min walking and gradually increased to 30 min for at least 5 days weekly. They received information about the health benefits of increasing PA both verbally and written. Furthermore, every pregnant woman in the intervention group was contacted once a week by telephone, while women in the control group were followed according to their antenatal schedule and received the standard follow-up care. All women in both groups were instructed to avoid dessert, sweets, and soft drink in their daily dietary intake as well as to reduce the amount of starchy foods and increase vegetable and protein consumption. The fourth interview was at 20-week gestation for all pregnant women in both groups for routine follow-up. All pregnant women received antenatal care in both groups and followed up according to their antenatal schedule. The fifth interview was conducted during the last 7 weeks of the walking program for further evaluation of the pedometer steps. All participants in both groups received the pedometer again to identify the average of their walking steps at the end of the study. Finally, the six interviews were approached to assess the HbA1c and fasting blood sugar at 24-week gestation as well as to record the pedometer steps [Table 1] and [Figure 1].
The research ethical committee of the Faculty of Nursing, Cairo University, accepted the research protocol with number of 00004025. Each participant was given detailed information on the study protocol, and all signed a written informed consent. The participants were also given information about the voluntary nature of the study and that they could withdraw from the study at any time without explanation.
The statistical package for the social science (SPSS) for data analysis, version 16 (SPSS Inc., Chicago, IL, USA) was utilized. Descriptive analyses were conducted on the characteristics of women in both intervention and control groups (means, standard deviations, and proportions). Further, the hypothesis was tested through Student’s t-test (continuous data) to compare data of both groups and identify the statistical differences that presented in the form of mean and standard deviation, paired t-test to compare between both groups and identify the statistical differences before and after the interventions, and Chi-square tests to compare the statistical differences between both groups for data represented in nominal and categorical way. Statistical significance level was set to <0.05.
| Results|| |
Most of pregnant women in both groups had normal HbA1c level, had secondary education, and were employed. There were no significant differences among the two groups regarding their age, gestational age, BMI at study entry, HbA1c, fasting blood sugar, education levels, and occupation (P ≥ 0.05) [Table 2].
|Table 2: Characteristics of the pregnant women among the study and the control groups|
Click here to view
Regarding women’s physical activities at the study entry, the participants reported participation in light-intensity activities (1.5–2.9 METs) with a mean of 77.48 ± 4.35 MET-h/week in the intervention group versus 76.64 ± 4.44 MET-h/week in the control group. Furthermore, the mean household type activities in the intervention and the control groups were 56.42 ± 1.87 and 56.12 ± 2.52 MET-h-week, respectively. Pedometer step analysis classified women as “low active” with mean of 2530 ± 466.42 steps/day in the intervention group versus 2579 ± 472.55 in the control group (ranged between 2011 and 3216 steps/day), with no statistical differences between the two groups P > 0.05 [Table 3].
|Table 3: Baseline pregnant women’s physical activity scores among the study and the control group (n=50)|
Click here to view
With regard to the glucose levels following the completion of walking plan at the 24-week gestation, data showed that there were no significant differences between the two groups with respect to the incidence of GDM (P = 0.16). Data reflect a decline in GDM incidence which is clinically significant. Furthermore, the intervention group had lower fasting plasma glucose levels and HbA1c compared to the control group (P ≤ 0.05). On the other hand, there were no statistical differences between the intervention and the control groups concerning weight gain during program’s duration [Table 4].
|Table 4: Comparison between the study and the control group related to the glucose level at 24-week gestation|
Click here to view
Comparing the intervention group with the control group related to their physical activities at 24-week gestation, data revealed that although the majority of women in both groups were classified as low active without significant differences (P > 0.07), there were statistically significant differences between the intervention and the control groups related to the mean of total pedometer steps/day, total minutes of walk/week, and walking MET min/week (P ≤ 0.0001). The pedometer steps in the intervention group ranged between 5123 and 7123 steps/day as compared to the 3862–6132 steps/day in the control group [Table 5].
|Table 5: Comparison between the study and the control group related to physical activities at 24-week gestation|
Click here to view
On comparison of results before and after walking program in the intervention group, data denoted that there were a statistical differences between the two groups readings related to HbA1c, fasting plasma glucose, pedometer steps counts (steps/day), total minutes of walk/week, and walking MET. Although walking steps and walking MET increased, the HbA1c and fasting plasma glucose mg/dl were increased (i.e., pre-diabetic phase). On the other hand, on comparison between two readings before and after walking program in the control group, data denoted that there were statistical differences between the two readings related to HbA1c, fasting plasma glucose, pedometer steps counts (steps/day), and walking MET [Table 6].
|Table 6: Comparison within each group; the intervention and the control groups of the glucose level and women’s physical activity scores before and after walking program|
Click here to view
| Discussion|| |
The results revealed that the middle-aged prediabetic, overweight pregnant women in the intervention group who walked 6000 steps or more per day had significantly lower rates of insulin resistance at 24 gestational weeks and lower frequency of gestational diabetes exposure than pregnant women in the control group. It is important to change lifestyle habits such as diet and exercise as GDM preventive measures. In the absence of any contraindications, it is advised that pregnant women perform physical exercise on most days of the week with moderate intensity of 30 min duration. The precise pathogenesis of increasing insulin sensitivity for physical activities and then reducing GDM frequency remains unclear. It may include many mechanisms, such as increasing insulin sensitivity through muscle contraction, enhancing antioxidant defense mechanisms, and altering adipokine profiles (i.e., adiponectin, leptin, and resistin). Although younger women may have lower expectations of risk and less desire to change conduct.
Further, the present study results denoted that although women’s physical activities increased in the intervention group as compared to the control group, there was a noticeable increasing in HbAc1 and fasting plasma glucose (i.e. pre-diabetic phase) among those women as women in the control group. The possible interpretation is that all women in the present study were already had one or more risk factors of diabetes, while the pregnancy in progress the risk was increased. In addition, all women recruited in the present study were physically inactive and risky to be diabetic, so shifting their life style from inactive to walk might not be enough to avoid an increasing in the plasma glucose level and to keep it in the normal range, and the only and the primary motive of women to walk an average of 6000 steps was to be healthy to deliver healthy newborns. Further, although all women in both groups received the nutritional instructions, the compliance with these instructions differs between women and not measured in the present study. Our results go along the same lines with Davenport et al. who reported that walking intervention could significantly reduce fasted glucose levels and 1 hour after meals in women with GDM. Moreover, women with walking intervention required fewer units of insulin per day and less frequency of injection. The middle-aged women can avoid metabolic syndrome by taking 6000 steps or more per day. Actually, walking about 6000 steps per day in healthy pregnant women in the second trimester can lessen the glucose levels. Further, a study reported that HbA1c level improvement is proportional to exercise intensity. On the other hand, other studies did not show a link between the levels of PA and the levels of fasting plasma glucose. A study also concluded that there is no or poor association between PA and levels of blood glucose in pregnant women with GDM.
Studies indicate that excessive gestational weight gain is another important independent risk factor for GDM. GDM risk increases as gestational weight gain levels rise. In addition, research showed that the correlation between the rate of gestational weight gain and GDM is mainly due to the increased the first trimester weight gain., Importantly, there was no significant difference in gestational weight gain found in this study between the intervention and the control groups at the end of 24 weeks’ gestation. We could not rule out the effect of meals (i.e., the number of meals, the amount, and type of food in each meal) although all women in both groups had dietary guidance. The present study which goes on the opposite with many studies reported that physical exercise at the beginning of pregnancy decreases mean gestational weight gain with no restriction on dietary intake.,,
The findings of the present study may be influenced by the degree of compliance of the pregnant women with the walking plan, quality and quantity of food they routinely received, and the fact that they believed, it was safe. Further, the follow-up of women was a difficult issue to be handled. Further studies that examine the effect of PA on overweight and obese pregnant women are needed.
| Conclusion|| |
Prediabetic, overweight pregnant women who have completed an average of 6000 steps walking or more per day early in the second trimester may have lower levels of insulin resistance and lower frequency of exposure to gestational diabetes. This walking program had been specifically designed to overcome many of the perceived barriers to be active during pregnancy reported in previous researches, including lack of time, work commitments, fatigue, and no access to exercise equipment. The study results are important in determining the efficacy of daily walking program in improving health outcomes of prediabetic, overweight pregnant women.
The author is thankful of all women who participated in this study.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Poston L, Caleyachetty R, Cnattingius S, Corvalán C, Uauy R, Herring S, et al
. Preconceptional and maternal obesity: Epidemiology and health consequences. Lancet Diabetes Endocrinol 2016;4:1025-36.
Silva JC, Amaral AR, Ferreira BD, Petry JF, Silva MR, Krelling PC. Obesity during pregnancy: Gestational complications and birth outcomes. Rev Bras Ginecol Obstet 2014;36:509-13.
Wei YM, Yang HX, Zhu WW, Liu XY, Meng WY, Wang YQ, et al
. Risk of adverse pregnancy outcomes stratified for pre-pregnancy body mass index. J Matern Fetal Neonatal Med 2016;29:2205-9.
Srichumchit S, Luewan S, Tongsong T. Outcomes of pregnancy with gestational diabetes mellitus. Int J Gynaecol Obstet 2015;131:251-4.
Hod M, Kapur A, McIntyre HD, FIGO Working Group on Hyperglycemia in Pregnancy, FIGO Pregnancy and Prevention of early NCD Committee. Evidence in support of the International Association of Diabetes in Pregnancy study groups’ criteria for diagnosing gestational diabetes mellitus worldwide in 2019. Am J Obstet Gynecol 2019;221:109-16.
Kim SY, England L, Wilson HG, Bish C, Satten GA, Dietz P. Percentage of gestational diabetes mellitus attributable to overweight and obesity. Am J Public Health 2010;100:1047-52.
van Poppel MN, Oostdam N, Eekhoff ME, Wouters MG, van Mechelen W, Catalano PM. Longitudinal relationship of physical activity with insulin sensitivity in overweight and obese pregnant women. J Clin Endocrinol Metab 2013;98:2929-35.
Khan T, Macaulay S, Norris SA, Micklesfield LK, Watson ED. Physical activity and the risk for gestational diabetes mellitus amongst pregnant women living in Soweto: A study protocol. BMC Womens Health 2016;16:66.
Cordero Y, Mottola MF, Vargas J, Blanco M, Barakat R. Exercise is associated with a reduction in gestational diabetes mellitus. Med Sci Sports Exerc 2015;47:1328-33.
Price BB, Amini SB, Kappeler K. Exercise in pregnancy: Effect on fitness and obstetric outcomes-a randomized trial. Med Sci Sports Exerc 2012;44:2263-9.
Barakat R, Pelaez M, Lopez C, Lucia A, Ruiz JR. Exercise during pregnancy and gestational diabetes-related adverse effects: A randomised controlled trial. Br J Sports Med 2013;47:630-6.
Poston L, Bell R, Croker H, Flynn AC, Godfrey KM, Goff L, et al
. Effect of a behavioural intervention in obese pregnant women (the UPBEAT study): A multicentre, randomised controlled trial. Lancet Diabetes Endocrinol 2015;3:767-77.
Simmons D, Devlieger R, van Assche A, Jans G, Galjaard S, Corcoy R, et al
. Effect of physical activity and/or healthy eating on GDM risk: The DALI lifestyle study. J Clin Endocrinol Metab 2017;102:903-13.
Dodd JM, Turnbull D, McPhee AJ, Deussen AR, Grivell RM, Yelland LN, et al
. Antenatal lifestyle advice for women who are overweight or obese: LIMIT randomised trial. BMJ 2014;348:g1285.
Stafne SN, Salvesen KÅ, Romundstad PR, Eggebø TM, Carlsen SM, Mørkved S. Regular exercise during pregnancy to prevent gestational diabetes: A randomized controlled trial. Obstet Gynecol 2012;119:29-36.
Baumeister RF, Heatherton TF, Tice DM. Losing control: How and why people fail at self-regulation. San Diego, CA: Academic Press;1994.
Chasan-Taber L, Schmidt MD, Roberts DE, Hosmer D, Markenson G, Freedson PS. Development and validation of a pregnancy physical activity questionnaire. Med Sci Sports Exerc 2004;36:1750-60.
Ainsworth BE, Haskell WL, Whitt MC, Irwin ML, Swartz AM, Strath SJ, et al
. Compendium of physical activities: An update of activity codes and MET intensities. Med Sci Sports Exerc 2000;32:S498-504.
White DK, Tudor-Locke C, Zhang Y, Fielding R, LaValley M, Felson DT, et al
. Daily walking and the risk of incident functional limitation in knee osteoarthritis: An observational study. Arthritis Care Res (Hoboken) 2014;66:1328-36.
Nascimento SL, Surita FG, Godoy AC, Kasawara KT, Morais SS. Physical activity patterns and factors related to exercise during pregnancy: A cross sectional study. PLoS One 2015;10:e0128953.
Golbidi S, Laher I. Potential mechanisms of exercise in gestational diabetes. J Nutr Metab 2013;2013:285948.
Morrison MK, Lowe JM, Collins CE. Perceived risk of Type 2 diabetes in Australian women with a recent history of gestational diabetes mellitus. Diabet Med 2010;27:882-6.
Davenport MH, Mottola MF, McManus R, Gratton R. A walking intervention improves capillary glucose control in women with gestational diabetes mellitus: A pilot study. Appl Physiol Nutr Metab 2008;33:511-7.
Colpani V, Oppermann K, Spritzer PM. Association between habitual physical activity and lower cardiovascular risk in premenopausal, peri-menopausal, and postmenopausal women: A population-based study. Menopause 2013;20:525-31.
Hayashi A, Matsuzaki M, Kusaka M, Shiraishi M, Haruna M. Daily walking decreases casual glucose level among pregnant women in the second trimester. Drug Discov Ther 2016;10:218-22.
Tamura Y, Tanaka Y, Sato F, Choi JB, Watada H, Niwa M, et al
. Effects of diet and exercise on muscle and liver intracellular lipid contents and insulin sensitivity in type 2 diabetic patients. J Clin Endocrinol Metab 2005;90:3191-6.
Idowu AT. Physical activity and glucose tolerance in overweight and obese pregnant women (Master’s Thesis). Norway, Trondheim;2015. Available from: https://core.ac.uk/reader/52117943. [Last accessed on 2020 Jan 20].
Mishra S, Kishore S. Effect of physical activity during pregnancy on gestational diabetes mellitus. Indian J Endocrinol Metab 2018;22:661-71.
Hedderson MM, Gunderson EP, Ferrara A. Gestational weight gain and risk of gestational diabetes mellitus. Obstet Gynecol 2010;115:597-604.
Wang C, Wei Y, Zhang X, Zhang Y, Xu Q, Sun Y, et al
. A randomized clinical trial of exercise during pregnancy to prevent gestational diabetes mellitus and improve pregnancy outcome in overweight and obese pregnant women. Am J Obstet Gynecol 2017;216:340-51.
Hantoushzadeh S, Sheikh M, Bosaghzadeh Z, Ghotbizadeh F, Tarafdari A, Panahi Z, et al
. The impact of gestational weight gain in different trimesters of pregnancy on glucose challenge test and gestational diabetes. Postgrad Med J 2016;92:520-4.
Koivusalo SB, Rönö K, Klemetti MM, Roine RP, Lindström J, Erkkola M, et al
. Gestational diabetes mellitus can be prevented by lifestyle intervention: The Finnish gestational diabetes prevention study (radiel): A randomized controlled trial. Diabetes Care 2016;39:24-30.
Oostdam N, Van Poppel MN, Wouters MG, Eekhoff EM, Bekedam DJ, Kuchenbecker WK, et al
. No effect of the fit for 2 exercise programme on blood glucose, insulin sensitivity, and birth weight in pregnant women who were overweight and at risk for gestational diabetes: Results of a randomized controlled trial. BJOG 2012;119:1098-107.
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]