The Role of Exercise in Reducing the Risks of Gestational Diabetes Mellitus

Abstract

Women's Health (2013) 9(6), [569][570][571][572][573][574][575][576][577][578][579][580][581] support the demands of fetal growth. A progressive and marked insulin resistance develops in maternal skeletal muscle, beginning around mid-pregnancy and progressing during the third trimester to levels that approximate the insulin resistance seen in T2DM [9]. Hormones and adipo kines secreted from the placenta, including TNF-a, placental lactogen, placental growth hormone, cortisol and progesterone, are probable triggers of insulin resistance in pregnancy, owing to rapid reversal at delivery [10].Normal pregnancy is characterized by increased insulin secretion from pancreatic b cells to compensate for peripheral insulin resistance. This can be displayed as a hyperbolic relationship between insulin sensitivity (the inverse of insulin resistance) and insulin secretion from pancreatic b cells (Figure 2). The development of GDM occurs when a mother does not secrete enough insulin in order to be able to meet the metabolic stress of peripheral insulin resistance. The reciprocal relation ship is preserved in most GDM women, but occurs at much lower level of insulin secretion. That is, women with GDM secrete 40-70% less insulin for any degree of insulin resistance [11,12]. Therefore, pregnancy-induced insulin resistance may unmask the b-cell dysfunction characteristic of GDM [13].Serial assessments of insulin sensitivity starting before pregnancy have also demonstrated slightly greater insulin resistance persisting into the third trimester in women with GDM compared with normal pregnant women [11]. This resistance applies to both the action of insulin Gestational diabetes mellitus & maternal obesityGestational diabetes mellitus (GDM) is the most common medical complication of pregnancy and is defined as glucose intolerance or high blood glucose concentrations (hyperglycemia), with onset or first recognition during pregnancy. The prevalence of GDM varies from 1 to 20% and is rising worldwide in line with increasing trends of maternal obesity and Type 2 diabetes mellitus (T2DM) [1,2]. The incidence of GDM rises disproportionately with increasing obesity. A recent meta-analysis of 20 population-based studies estimated that the risk of developing GDM is 2.14-fold higher for overweight (BMI: 25.0-29.9), 3.56-fold higher for obese (BMI: ≥30.0) and 8.56-fold higher for severely obese women (BMI: ≥40.0) compared with normal weight pregnant women (BMI: <25.0) [3]. Obesity and GDM have been recognized as independent risk factors for a number of adverse maternal and fetal outcomes, including diabetes, hypertension, operative deliveries, macrosomia and neonatal complications [4][5][6]. More recently, we have begun to understand that maternal obesity and GDM are also associated with significant lifelong consequences for the next generation [7,8]. As obesity and GDM share many of the same health consequences, obese women and their offspring are at a greater risk for adverse outcomes (Figure 1). Pathophysiology of GDMDuring normal pregnancy,...

Exercise improves glycaemic control in women diagnosed with gestational diabetes mellitus: a systematic review

“…46,[49][50][51] It remains uncertain whether adjunctive exercise, in controlling glycaemic levels in women with GDM, has the potential to reduce or delay the need for insulin therapy, which can be costly, invasive and poorly accepted by women. 45,54 This is relevant because high insulin levels, as occur in hyperglycaemia, may be associated with vascular damage; so the lower the dose of insulin required, the better. 55 In the exercise intervention groups, it was observed that there were fewer women requiring insulin (26 out of 194, 13%) compared with those receiving standard care (39 out of 190, 21%), although the meta-analysis of the studies contributing to these pooled data did not identify a statistically significant difference.…”

Role of Exercise in Reducing Gestational Diabetes Mellitus

“…6 Fetal concerns during a GDM pregnancy are excessive fetal growth and fetal distress that warrants suggested frequent fetal biophysical profiles and ultrasound assessments of fetal growth. 21 MNT and exercise in GDM women have been shown to lower rates of large-forgestational-age infants and macrosomia without increasing small-for-gestationalage babies. 22…”

“…Exercise is considered an adjunctive therapy for women with GDM by many professional societies 21 and is promoted in lifestyle change. 6 Despite professional endorsement there are only a few wellcontrolled studies examining the role of exercise in combination with MNT in GDM management.…”

“…25 Furthermore, GDM patients randomized to 45 minutes of stationary cycling at 50% of aerobic capacity showed glycemic control comparable with a group of GDM women on insulin therapy, 26 suggesting that exercise can be offered as a safe and efficient adjunctive therapy for women with GDM. 21 Because of the different exercise modalities (frequency, intensity, time/duration, and type of exercise) it is difficult to identify the best exercise prescription for women with GDM 27 ; however, a recent review suggested that women with GDM should perform both aerobic and resistance exercise at a mild to moderate intensity, for 3 to 4 times per week for 30 to 60 minutes per session. 12 Women with GDM who are receiving insulin therapy should be aware of a rare but possible complication.…”

Maternal inflammation during late pregnancy is lower in physically active compared with inactive obese women

“…The physiological and hormonal changes associated with pregnancy magnify this risk during and after pregnancy by causing an increase in adiposity and insulin resistance (Artal 2015). In pregnant women of normal body weight, physical activity reduces inflammation (Hawkins et al 2014; Wang et al 2014), as well as improves maternal insulin sensitivity (Hopkins and Artal 2013). In obese pregnant women, physical activity may decrease insulin resistance (van Poppel et al 2014).…”