Research Updates 2001-2005

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The staff of Dancing Thru Pregnancy® (DTP) regularly monitors research and applies findings to the development of best practices, in order to keep our programs and educational seminars safe, effective, and up-to-date.

Summer 2005 – moderate exercise and breast milk; adverse effects of static stretching during warm-up activity; physical activity, coping mechanisms, and women’s experience of birth; the effectiveness of strengthening exercises for postpartum pelvic girdle pain

Winter 2005 – potential mechanism whereby exercise may reduce the risk of preeclampsia; prenatal activity questionnaire; and, exercise and postpartum well-being

Winter 2004 – prenatal aerobic activity reduces risk of preeclampsia and low birth weight, and improves tolerance for labor; postpartum group exercise may benefit mom

Fall 2003 – maternal exercise and its impact on fetal oxygen, substrate delivery, hormone response

Summer 2002 – maternal exercise, oxidative stress and long term cardiovascular impact on offspring health

Spring 2002 – review of research findings on exercise in pregnancy and the early postpartum period

Summer 2001– maternal aerobics and birth outcomes in first time mothers, portal vein flow, and metabolic markers; strength training in late gestation

For research on nutrition, go to Nutrition in the section under Tips/Classes.

For research on menopause, hormone replacement and exercise, go to Menopause below.

Summer 2005

A study on breast milk in exercising moms concluded that moms who are breastfeeding can exercise moderately without diminishing the amount of vital fatty acids in their breast milk. In fact, the concentration of certain fats involved in infant growth and development may temporarily increase right after a bout of moderate activity. The authors suggest that exercise could benefit breastfeeding mothers and babies.

Source: Bopp M; Lovelady C; Hunter C; Kinsella T. (2005). Maternal diet and exercise: Effects on long-chain polyunsaturated fatty acid concentrations in breast milk. J Am Diet Assoc, 105(7):1098-1103.

Researchers found that stretching to the point of discomfort can adversely affect performance tests of static balance and movement and reaction times in healthy males. Furthermore, inserting a stretching routine within a rest period of a warm-up nullifies a small benefit in movement and reaction times and balance performance. These findings support DTP’s long-standing recommendation that range of motion (ROM) activities and games be employed, rather than static stretching, in the lead up to aerobic activity.

Source: Behm DG; Bambury A; Cahill F; Power K. (2004). Effect of acute static stretching on force, balance, reaction time, and movement time. Med Sci Sport Ex, 36(8):1397-402.

The following article lends support to the idea that physical activity that includes coping techniques for labor may well contribute to a woman’s satisfaction with her experience of birth.

The pain experiences of culturally diverse childbearing women are described based on a secondary analysis of narrative data from phenomenologic studies of the meaning of childbirth. Findings by Callister, et al. indicate that understanding the meaning of pain, women’s perceptions of pain, and culturally bound pain behaviors is fundamental in order for nurses to facilitate satisfying birth experiences for culturally diverse women. Study participants were interviewed in the hospital after giving birth or in their homes within the first weeks after having a baby. Transcripts of interviews with childbearing women who lived in North and Central America, Scandinavia, the Middle East, the People’s Republic of China, and Tonga were analyzed. Participants described their attitudes toward, perceptions of, and the meaning of childbirth pain. Culturally bound behavior in response to childbirth pain was also articulated. A variety of coping mechanisms were used by women to deal with the pain.

Source: Callister, et al. (2003). The pain of childbirth: Perceptions of culturally diverse women. Pain Manag Nurs, 4(4):145-154.

Exercises designed to strengthen the muscles that support that pelvic girdle can ease postpartum pelvic girdle pain. After treatment and at one year postpartum, women who performed stabilizing exercises reported reduced pain intensity and disability, and improved quality of life. According to researchers, an individualized treatment approach with specific stabilizing exercises appears to be more effective than physical therapy without specific stabilizing exercises for women with pelvic girdle pain after pregnancy.

Source: Stuge B; Laerum E; Kirkesola G; Vollestad N. (2004). The efficacy of a treatment program focusing on specific stabilizing exercises for pelvic girdle pain after pregnancy: a randomized controlled trial. Spine, 29(4):351-9.

Winter 2005

Based on the epidemiological findings of Sorenson et al (see Winter 2004 update) and others, the theory has been proposed that there are three mechanisms that might account for the reduced level of preeclampsia found in physically fit pregnant women. These are 1) stimulation of placental growth and vascularity, 2) reduction of oxidative stress, and 3) exercise-induced reversal of maternal endothelial dysfunction. The authors recommend future research include prospective epidemiologic case-control studies that accurately measure occupational and recreational physical activity during pregnancy, as well as controlled randomized clinical trials that look at the effect of maternal exercise on biochemical markers for endothelial dysfunction, placental dysfunction and oxidative stress.

Source: Weissgerber, TL, Wolfe , LA , and Davies, GAL. The Role of Regular Physical Activity in Preeclampsia Prevention. Medicine and Science in Sports and Exercise 36(12):2024-2031, 2004 Dec.

Researchers developed and tested a pregnancy physical activity questionnaire (PPAQ) to ascertain the type, duration, and frequency of physical activities performed by pregnant women in household/caregiving, occupational, sports/exercise, transportation and inactivity. The authors conclude that their research indicates the PPAQ is a reliable and reasonably accurate measure of a broad range of physical activities during pregnancy.

Source: Chasan-Taber, L, Schmidt , MD , Roberts, DE, Hosmer, D, Markenson, G, Freedson, PS. Development and Validation of a Pregnancy Physical Actvity Quesionnnaire. Medicine and Science in Sports and Exercise 36(10):1750-1760, 2004 Oct.

In a study that examined maternal well-being in postpartum subjects on the basis of sport/exercise (SE) activity prepregnancy to postpartum, researchers found that postpartum SE, education and socioeconomic status were predictors of maternal well-being and that family and social support were significant factors in maintaining or increasing SE. These findings support the findings of Sampselle et al (see Spring 2002 update, reference 12).

Source: Blum, JW, Beaudoin, CM, Caton-Lemos, L. Physical activity patterns and maternal well-being in postpartum women. Maternal and Child Health Journal 8(3):163-169, 2004, Sept.

Winter 2004

Recreational aerobic physical activity in early pregnancy and/or the year prior to pregnancy is associated witha a significant reduction in the risk of preeclampsia. Depending on the intensity of exercise, risk was reduced by 24% to 54%.

Source: Sorenson, TK et al. Recreational physical activity during pregnancy and risk of preeclampsia. Hypertension. 41(6):1273-80, 2003 Jun.

Recreational physical activity reduces the risk of low birth weight infants.

Source: Leiferman JA. Evenson KR. The effect of regular leisure physical activity on birth outcomes. Maternal & Child Health Journal. 7(1):59-64, 2003 Mar.

Women who do aerobic exercise through the entire pregnancy tolerate labor better physically than those who do not. Regular maternal exercise may reduce labor-induced lipid peroxidation by improving the defense capabilities against free radical generation.

Source: Kobe H. Nakai A. Koshino T. Araki T. Effect of regular maternal exercise on lipid peroxidation levels and antioxidant enzymatic activities before and after delivery. Journal of Nippon Medical School . 69(6):542-8, 2002 Dec.

There is increasing evidence that women who pursue group exercise in the postpartum period are at reduced risk for postpartum depression. This study suggest additional studies are needed.

Source: Currie J. Pramwalking as postnatal exercise and support. Australian Journal of Midwifery14(2):21-5, 2001 Jun.

Fall 2003

Sustained bouts of maternal exercise during pregnancy cause an acute reduction in oxygen and nutrient delivery to the placental site. The decreased flow also initiates a slight fall in intervillous and fetal pO2 which initiates a fetal sympathetic response. This, coupled with hemoconcentration and improved placental perfusion balance, maintains fetal tissue perfusion and oxygen uptake. Exercise training during pregnancy (regular bouts of sustained exercise) increases resting maternal (and perhaps fetal) plasma volume, intervillous space blood volume, cardiac output and placental function. These changes buffer the acute reductions in oxygen and nutrient delivery during exercise and probably increase 24 h nutrient delivery to the placental site. Thus, the effect of any given exercise regimen on fetal growth and size at birth is dependent on the type, frequency, intensity and duration of the exercise as well as the time point in the pregnancy when the exercise is performed. Maternal carbohydrate intake is yet another modifying factor. Beginning a moderate exercise regimen increases both anatomic markers of placental function and size at birth while maintaining a rigorous exercise regimen throughout pregnancy selectively reduces growth of the fetal fat organ and size at birth. Likewise, decreasing exercise performance in late-pregnancy increases size at birth while increasing exercise performance decreases it. Finally, the infants born of exercising women who eat carbohydrates which elevate 24 h blood glucose levels are large at birth irrespective of exercise performance.

Source: Clapp JF 3rd. The effects of maternal exercise on fetal oxygenation and feto-placental growth. European Journal of Obstetrics, Gynecology, & Reproductive Biology. 110 Suppl 1:S80-5, 2003 September 22.

Examining the effects of maternal exercise on substrate utilization and hormone responses, Bessinger et al found no significant differences between exercise trials in oxygen uptake, respiratory exchange ratio, or heart rate. Pregnancy elevated resting triglyceride levels but lowered plasma glucose levels. Exercise during pregnancy caused a reduction in plasma glucose levels but elevated circulating triglyceride levels (P <.05). Resting levels of cortisol, growth hormone, and insulin were elevated during pregnancy compared with after delivery, but resting glucagon levels were not affected bypregnancy. Exercise caused circulating levels of cortisol, growth hormone, and glucagon to increase (P <.05). The exercise-induced change in the cortisol level was greater during pregnancy than that after delivery. The exercise-induced changes in growth hormone and glucagon levels were greatest after delivery compared with those during pregnancy (P <.05). Exercise reduced insulin levels (P <.05), with the greatest reduction at 33 weeks’ gestation. There were no significant differences in urine urea nitrogen excretion as a result of exercise. The authors concluded that protein appears to be a relatively unimportant fuel during a 30-minute bout of moderate intensity exercise in this group of women evaluated during pregnancy and after delivery. Furthermore, a 30-minute bout of moderate intensity exercise would not be expected to compromise fetal amino acid availability.

Source: Bessinger RC. McMurray RG. Hackney AC. Substrate utilization and hormonal responses to moderate intensity exercise during pregnancy and after delivery. American Journal of Obstetrics & Gynecology. 186(4):757-64, 2002 Apr.

Summer 2002

The following excerpt from a recent review on the mechanisms of cardiovascular diseases does a good job of elucidating one of the reasons pregnant women should be exercising. Persons wishing to read the entire article and examine the references (numbers included within the text below), should refer to MedLine or the ACOG website.

Source: Napoli , Claudio MD, PhD; Lerman, Lilach O. MD, PhD

Involvement of Oxidation-Sensitive Mechanisms in the Cardiovascular Effects of Hypercholesterolemia [Review]. Mayo Clinic Proceedings 76(6):619-631, 2001

Excerpt:

EFFECTS OF HYPERCHOLESTEROLEMIA AND INCREASED OXIDATION ON EARLY ATHEROGENESIS IN HUMANS

Until recently, atherogenesis was thought to begin during late childhood, although fatty streaks had occasionally been observed in younger children.163,164 However, a systematic morphometric analysis of the entire aorta of premature human fetuses demonstrated that formation of fatty streaks, the precursors of more advanced atherosclerotic lesions, is prevalent in all fetal aortas and that their number and size are markedly increased in fetuses whose mothers had hypercholesterolemia during pregnancy.138 Fetal lesions contained typical components of early atherosclerotic lesions, such as native and oxidized LDL and macrophages, and their distribution reflected that of more advanced atherosclerosis seen in adults, ie, most extensive in the abdominal aorta, followed by the aortic arch. This suggests that, during the earlier stages of pregnancy, maternal hypercholesterolemia may promote early atherogenesis in the fetus.165,166 The assumption that LDL oxidation is a contributor to atherogenesis in fetal arteries was also supported by a later study 167 in which the middle cerebral and basilar arteries of fetuses contained significantly smaller lesions than the aorta and common carotid arteries. Determinations of the arterial activities of oxygen-radical scavengers, such as manganese superoxide dismutase, catalase, and glutathione peroxidase, indicated that overall intracranial arteries of human fetuses were better protected against oxidation than extracranial arteries.167 These results are consistent with the assumption that better protection against free radical-mediated oxidation may contribute to the greater resistance of intracranial arteries to hypercholesterolemia-induced atherogenesis and vascular dysfunction.168

To investigate whether fetal lesions regress and/or whether they influence atherogenesis during childhood and adolescence, the Fate of Early Lesions in Children (FELIC) study was designed.139 Atherosclerosis was established by computer-assisted image analysis in normocholesterolemic children and was found to progress much faster in children whose mothers had hypercholesterolemia during pregnancy than in children of normocholesterolemic mothers, despite normal lipid profiles in both groups of children. None of the risk factors of atherogenesis assessed in these children could account for the faster atherogenesis in children of hypercholesterolemic mothers. Although parental genetic differences are likely to contribute to the different susceptibility of children to the disease, we postulated that maternal-fetal hypercholesterolemia induced constitutive changes in gene expression in arterial cells, which were associated with a greater susceptibility to the disease later in life.165,166 A recent study demonstrated that fetal lesions in the rabbit can be reduced with vitamin E or cholestyramine treatment of the hypercholesterolemic mothers during pregnancy.169

Maternal hypercholesterolemia during gestation should therefore be added to the list of risk factors determining the need for monitoring and for preventive therapy.170 Current clinical guidelines place great emphasis on early detection of hypercholesterolemia,171 although such screening would not detect an increased risk associated with maternal hypercholesterolemia in normocholesterolemic subjects. An intense lipid-lowering intervention may be a therapeutic option for children with several risk factors. As indicated by a recent meta-analysis of studies on the development of coronary artery disease in children and adolescents,172 an average reduction of LDL cholesterol by 25% can be obtained with statins in combination with a lipid-lowering diet. Statins are generally well tolerated in children and adolescents, and current data do not indicate adverse effects on growth and sexual development in male adolescents. In high-risk children, follow-up may need to include an attempt for an earlier than usual noninvasive diagnosis of atherosclerosis. Potential approaches include measurement of coronary flow velocity in the distal left anterior descending ( LAD ) coronary artery with transthoracic Doppler echocardiography,173 determination of the degree of stenosis in the proximal LAD coronary artery by transesophageal Doppler study 174 or magnetic resonance imaging,175 measurement of coronary flow reserve in the LAD coronary artery by contrast-enhanced transthoracic second harmonic echocardiography/Doppler study,176 or quantification of coronary calcifications by electron beam computed tomography.177-179

Another clinical scenario that may involve dyslipidemia and oxidative stress is the pregnancy-related preeclampsia syndrome, the etiology and pathogenesis of which remain poorly understood.180 Recent evidence points to a pro-oxidant shift in preeclampsia, and ROS and/or their metabolites have been hypothesized to ultimately compromise the vasodilatory, antiaggregatory, and barrier defense functions of the endothelium. Failure of flow-induced shear stress may contribute to the gestational hypertension of preeclampsia.181 Maternal dyslipidemia and altered iron kinetics in preeclampsia may potentially affect disease progression.180 Oxidative stress as a result of interaction of fetoplacental and maternal factors and autoimmune reaction may lead to the manifestations of preeclampsia. For example, interaction of maternal neutrophils and oxidized lipids with placental cells and placenta-derived factors can engender a vicious cycle of oxidative stress that may ultimately cause widespread endothelial cell dysfunction and physiological perturbations downstream of cellular signaling. A randomized controlled trial recently showed that vitamin C and E supplementation may be beneficial in women with or at increased risk for preeclampsia,182 suggesting that the “primum movent” of the disease was increased lipid oxidation during pregnancy.

CONCLUSIONS

Hypercholesterolemia is a common clinical disorder that may begin early in life in humans, and it subsequently promotes atherogenesis by injuring the vascular wall, thereby impairing a multitude of functions and signaling pathways that it controls and leading to development of atheromatous plaques. The underlying mechanisms responsible for these abnormalities may emanate from activation of oxidation-sensitive mechanisms, increased oxidation of LDL cholesterol, and quenching of NO. This cascade of events can begin as early as during pregnancy, altering the complex framework of signaling network in the arterial wall. Novel treatment strategies* that attempt to decrease oxidation and restore bioavailability of NO have the potential to decrease morphologic and functional arterial damage and improve cardiovascular outcomes in patients with hypercholesterolemia.

* Ann’s note: “Novel treatment strategies” refers to exercise, among other things.

Spring 2002

Review of Research Findings on Exercise in Pregnancy

Note: Since the original posting of this update, Kramer, in his Cochrane review, raised doubts about the inconsistency and low numbers in the methodology of research concluding that fitness impacts labor, birth or fetal outcomes, although he does conclude that maternal exercise does lead to physical fitness, and improved self-image and confidence in one’s body. None-the-less, on the basis of subsequent research and a re-review of research previously examined, DTP holds to the view that fitness improves labor and birth outcomes, and may well be a factor in reducing the need for medical intervention in labor. However, because of the growing need for obstetricians and midwives to practice defensive medicine in the current legal climate, it may be doubtful that this outcome can be cleanly assessed.

For the last fifteen years, it has been well understood that women who are fit may have shorter active labors with a significantly lower rate of cesarean births [1,2]. More recent evidence is showing that women who begin regular, moderate exercise in the first trimester, and continue through their pregnancy, also benefit. One study has shown that first time mothers who do not exercise are 4.5 times as likely to require a cesarean birth than women who begin exercise in the first trimester [3].

Regular, moderate physical activity begun in early pregnancy is healthy for both mother and baby. One of the major reasons the baby benefits is that the placenta–the organ of circulation bringing nutrients and oxygen to the umbilical cord for delivery to the fetus–is larger and more extensively developed in exercising mothers [4-6]. In addition, blood flow to the uterus, or womb, is greater in exercising women [7]. As long as there are no medical problems, healthy women should be encouraged to participate in regular, moderate exercise once they have been screened by the obstetrician or nurse-midwife and given the okay to participate.

A reason exercise is beneficial for the mom is its ability to reduce discomfort. A well-designed prenatal regimen will help with a number of pregnancy-related physical problems [8-11]. In addition, a group class has many benefits. Research studies on various periods in women’s lives tell us that when undergoing major life changes, there are benefits from being with other similar women. In addition, women who return to vigorous activty prior to six weeks postpartum have less weight to lose, score better on maternal adaptation tests, and are in a happier mood than sedentary women [12]

1. Clapp, JF 3rd and Dickstein, S. 1984. Endurance exercise and pregnancy outcome, Med Sci Sports Exerc 16(6): 556-62.

2. Hall , DC and Kaufmann, DA. 1987. Effects of aerobic and strength conditioning on pregnancy outcomes, Am J Ob /Gyn, 157(5): 1199-1203.

3. Bungum, TJ, Peaslee, DL, Jackson , AW and Perez , MA . 2000. Exercise during pregnancy and type of delivery in nulliparae, JOGNN 29(3): 258-64.

4. Clapp, JF, et al. 2000. Beginning regular exercise in early pregnancy: effect on fetoplacental growth, Am J Ob Gyn 183: 1484-8.

5. Clapp, JF 3rd and Rizk, K. 1992. Effect of recreational exercise on midtrimester placental growth, Am J Ob Gyn 167(6): 1518-21.

6. Jackson, MR, Gott, P, Lyle, SF, Ritchie, JW and Clapp, JF 3rd. 1995. The effects of maternal aerobic exercise on human placental development: placental volumetric composition and surface areas, Placenta 16(2): 179-91.

7. Clapp, JF, Stepanchak, W, Tomaselli, J, Kortan, M and Faneslow, S. 2000. Portal vein blood flow–effects of pregnancy, gravity and exercise, Am J Ob Gyn 183(1): 167-72.

8. Ostgaard, HC, Zetherstrom, G, Roos-Hansson, E, Svanberg, B. 1994. Reduction of back and posterior pelvic pain in pregnancy, Spine 19(8): 894-900.

9. McIntyre , IN and Broadhurst, NA. 1996. Effective treatment of low back pain in pregnancy, Aust Fam Prac 25(9 Suppl 2): S65-67.

10. Andrews, CM and O’Neil, LM. 1994. Use of pelvic tilt exercise for ligament pain relief, J Nurse Midwif 39(6): 370.

11. Sampselle, CM, Miller, JM, Mims, BL, DeLancey, JO, Ashton-Miller, JA and Antonakos, CL. 1998. Effect of pelvic muscle exercise on transient incontinence during pregnancy and after birth, Ob Gyn 91(3): 406-12.

12. Sampselle, CM, Seng, J, Yeo, SA, Killion, C and Oakley, D. 1999. Physical activity and postpartum well-being, JOGNN 28(1): 41-9.

Summer 2001

Researchers assessed the association between participation in aerobic exercise during the first two trimesters of pregnancy and type of delivery in nulliparous women. They concluded that regular participation in physical activity during the firt two trimersters of pregnancy may be associated with reduced risk for cesarean delivery in nulliparous women.

Source: Bungum TJ. Peaslee DL, Jackson AW, Perez MA- Exercise during pregnancy and type of delivery in nulliparae. Journal of Obstetric, Gynecologic, & Neonatal Nursing 29(3):258:64, 2000, May-Jun.

Researchers tested the hypothesis that pregnancy increases portal vein blood flow and that regular exercise training during pregnancy limits the flow redistribution away from the splanchnic and uterine circulations in response to either gravitational or exercise-induced hemodynamic stress. Conclusions: Portal vein blood flow rises significantly during pregnancy, and flow redistribution away from the splanchnic and uterine circulations in response to severe hemodynamic stress is reduced by exercise training in mid and late pregnancy.

Source: Clapp JF 3rd, Stepanchak W., Tomaselli J., Kortan M, Faneslow S.- Portal vein blood flow-effects of pregnancy, gravity, and exercise. American Journal of Obstetrics & Gynecology. 183(1):167-72, 2000 Jul.

This study detected a strong trend that 10 weeks of moderate exercise (3 times a week, 30 minutes at RPE of 13, during weeks of 18-28) lowered the diastolic blood pressure among pregnant women at risk of hypertensive disorders. The reductions were probably due to the effect of exercise itself, not to weight or overall daily physical activity levels.

Source: Yeo S, Steele NM , Chang MC, Leclaire SM, Ronis DL, Hayashi R

Effect of exercise on blood pressure in pregnant women with a high risk of gestational hypertensive disorders. Journal of Reproductive Medicine. 45(4):293-8, 2000 Apr.

Pregnancy and exercise have opposite effects on fat mass and insulin resistance. This study tested the hypotheses that exercise during pregnancy alters the pregnancy-associated increases in the levels of tumor necrosis factor alpha and leptin, and that the changes in tumor necrosis factor alpha and leptin concentrations during pregnany continue to reflect changes in fat masses.

Conclusions: Regular weight-bearing exercise during pregnancy suppresses the pregnancy-associated changes normally seen in both tumor necrosis factor alpha and leptin. The decrease in leptin reflects decreased fat accretion, and researchers speculate that the changes in tumor necrosis factor alpha may reflect a change in insulin resistance.

Source: Clapp JR 3rd, Kiess W. Effects of pregnancy and exercise on concentrations of the metabolic markers tumor necrosis factor alpha and leptin. American Journal of Obstetrics & Gynecology. 182(2):300-6, 2000 Feb.

This study examines cardiovascular responses to strength conditioning exercises. Maternal heart rate and blood pressure and fetal heart rat (FHR) responses were measured in both the supine (30 degrees tilt) and seated postures during handgrip (HG), single-leg extension (SL), and double-leg extension (DL) exercise. Pregnant subjects exhibited higher heart rates but similar blood pressure responses to control subjects under all experimental conditions. Significant increases were observed for the frequency of FHR accelerations (0.10 to 0.27/min) from rest to DL in the sitting posture at 90% RM. Moderate fetal bradycardia was observed occasionally in the tilted supine posture at rest and both during (SL, DL) and following (HG, SL, DL) exercise, suggesting that this posture should be avoided in late gestation.

Source: Avery ND, Stocking KD, Tranmer JE, Davies GA , Wolfe LA. Fetal responses to maternal strength conditioning exercises in late gestation. Canadian Journal of Applied Physiology. 24(4):362-76, 1999 Aug.

Researchers from the Department of Ob/Gyn, University of Sydney , New South Wales , Australia , examined [maternal] postnatal distress, eating, exercise, and vomiting before and during pregnancy. They found that postnatal distress was associated with body weight and shape concerns, disordered eating before and during pregnancy, and with vomiting during pregnancy. Low intensity exercise duirng early pregnancy played a protective role. The authors recommend that women with eating disorders should be considered at risk for postnatal problems. The authors found four variables that were associated with greater distress: fear of weight gain before and during pregnancy, being distracted by thoughts of food during pregnancy, being afraid of gaining more weight than the pregnancy would explain, and vomiting more frequently during the first 3-4 months of pregnancy. Participating in low-intensity exercise for reasons of shape and weight during months 3-4 of pregnancy accounted for less distress. The most distressed mothers were suffering from an eating disorder at the time of pregnancy. The binge and/or purge type of eating disorder was associated with more distress than a food restriction type of disorder.

Source: Abraham S. Taylor A. Conti J. Postnatal depression, eating, exercise, and vomiting before and during pregnancy. International Journal of Eating Disorders. 29(4):482-7, 2001 May.

Menopause

Exercise in Midlife and Older Women

This studied examined the relationship of changes in physical activity and mortality among older women (65 and older at baseline). 9518 community-dwelling white women where assessed at baseline; 7553 assessed at follow-up, median 5.7 years later. Walking and other physical activities; cause of death tracked for up to 12.5 years after baseline (6.7 years after follow up).

Compared with continually sedentary women, those who increased physical activity levels between baseline and follow-up had lower mortality from all causes, cardiovascular disease and cancer, independent of age, smoking, body mass index, comorbid conditions and baseline physcial activity. Associations between changes in physical activity and reduced mortality were similar in women with and without chronic dieseases but tended to be weaker among women aged at least 75 years and those in poor health. Women who were physically active at both visits also had lower all-cause mortality and cardiovascular mortality than sedentary women.

Source: Gregg, EW, Cauley, JA, Stone, K, et al. Relationship of Changes in Physical Activity and Mortality Among Older Women. JAMA, 289(18):2379-2386.

2002 Annoucements by the Women’s Health Initiative Writing Group

Risks and Benefits of Estrogen and Progestin in Healthy Postmenopausal Women. JAMA, 288(3):321-333, 2002 July 17.

The release of findings from the Women’s Health Initiative study on HRT has been a bombshell for many women taking hormone placement under the assumption that it provided protection again heart disease. While we have known for some time that certain cancers are linked to HRT , especially long-duration dosage, the disappearance of the mirage of protection of HRT against heart disease was a schock. But, the whole story is complex. There are both risks and benefits. The percentage of change in risk is great, but the numbers are very small. Per 10,000 person-years, there were 7 more CHD events, 8 more strokes, 8 more pulminary embolisms, 8 more invasive breast cancer cases, 6 fewer colorectal cancers and 5 fewer hip fractures.

It is helpful to review the description of the findings as published in the July 2002 press release from the National Heart, Lung, and Blood Institute (NHLBI) of the NIH:

41% increase in stroke

29% increase in heart attack

100% increase in venous thromboembolism

22% increase in CVD

26% increase in breast cancer

37% decrease in colorectal cancer

33% decrease in hip fracture

24% decrease in total fractures

No difference in total mortality (all cause mortality)

Related articles that may be of interest include:

Lacey, JV, Jr, Mink, PJ, Lubin, JH, et al. Menopausal Hormone Replacement Therapy and Risk of Ovarian Cancer. JAMA 288(3):334-341.

Chlebowski, RT, Hendrix, SL, Langer, RD, et al. Influence of Estrogen Plus Progestin on Breast Cancer and Mammography in Healthy Postmenopausal Women: The Women’s Health Initiative Randomized Trial. JAMA 289(24):3243-3253.

Li, CI, Malone, KE, Porter, NS, et al. Relationship Between Long Durations and Different Regimens of Hormone Therapy and Rist of Breast Cancer. JAMA 289(24):3254-3263.

Menopause Fitness: Brain, Mind, Mood and Exercise

The impact of exercise on mood in midlife is profound. Both chronic and acute exercise can have a positive effect on mood and reduce the level of somatic and vasomotor symptoms compared with non-exercisers, regardless of menopause status or whether or not a woman is taking hormone replacement [321]. In one study, the degree of a woman’s psychosomatic symptoms in perimenopause was found inversely related to the degree of exercise from her thirties on (less exercise produced greater feelings of “weakness”) and from her forties on (“nervousness” and “melancholia”) [2]. The researchers concluded that the greater the degree of exercise from her forties on, the lesser the degree of her symptoms after menopause, and that exercising moderately from the subjective point of view in the perimenopausal period may alleviate symptoms [2].

Hot flashes (vasomotor symptoms) are experienced at some point by perhaps 80 or 90% of women with a changing gynecological status in Western nations [3,4,5]. Temperature regulation requires integration of autonomic, endocrine and skeletomotor responses in the hypothalamus [6]. With estrogen at a low ebb, malfunctions in the body’s thermostat occur. The sensation of being overheated is related to the metabolism of the neurotransmitter norepinephrine, which is mediated by estrogen in the hypothalamus. The condition is aggravated by stress, which results in increased norepinephrine, but generally lessens postmenopausally. In addition, the increasing levels of FSH causes altered signals concerning the internal temperature set-point. The ability of exercise to contribute to stress management may well be a factor for reduction of vasomotor symptoms.

It is likely that adequate levels of estrogen in the female brain are necessary for memory storage and learning new tasks [7]. The parietal (frontal) lobes of the cerebral cortex are important for organizational thinking and are affected in early menopause by a changing estrogen concentration. This probably accounts for the reports of “fuzzy thinking” by midlife women. Alzheimer’s disease (AD), while related to estrogen levels, has many more dimensions than fuzzy thinking.

1. Slaven, L and Lee, C. 1997. Mood and symptom reporting among middle-aged women: the relationship between menopausal status, hormone replacement therapy, and exercise participation, Health Psychol 16(3): 203-8.

2. Ueda, M and Tokunaga, M. 2000. Effects of exercise experienced in the life stages on climacteric symptoms for females, J Physiol Anthro Appl Human Sci 19(4): 181-9.

3. Northrup, C. 1994. Women’s Bodies, Women’s Wisdom. NY: Bantam.

4. Kronenberg, F. 1990. Hot flashes: Epidemiology and physiology, Ann NY Acad Sci 592: 52-86.

5. McKinlay, SM and Jefferys, M. 1974. The menopausal syndrome, Brit J Preent Soc Med 28(2): 108.

6. Kandel, ER, Schwartz, JH and Jessell, TM. 1991. Principles of Neural Science, 3rd ed. Norwalk , CT : Appleton & Lange, pp. 752-53.

7. Barinaga, M. 1994. Watching the brain remake itself, Science (Dec. 2): 1475-76.