Physical activity before and during pregnancy and birth weight

Transcription

1 Note: for non-commercial purposes only The Power of Programming Developmental Origins of Adiposity and Long-Term Health Physical activity before and during pregnancy and birth weight Katrine M. Owe, PhD, Postdoc Norwegian Resource Centre for Women's Health, Oslo University hospital/ Division of Mental Health, Norwegian Institute of Public Health, Oslo, Norway Munich, March Norwegian Institute of Public Health

2 The Physical Activity Paradox

3 Outline Background Physical activity and Exercise Physical activity and Birth weight Large-for-gestational-age Mean Small-for-gestational-age

4 Definition of Physical activity A behaviour defined as any bodily movement produced by skeletal muscles that result in energy expenditure Caspersen, Powell & Christenson 1985 Leisure-time physical activity (LTPA) includes all kinds of activities one participates in during free time and is selected on the basis of personal interests and needs Bouchard & Shepard 1994 For example exercise

5 Definition of Exercise planned, structured, repetitive, and purposeful activity where the objective is to improve or maintain one or more components of physical fitness Caspersen, Powell & Christenson 1985 Aerobic exercise, strength, flexibility Non-weight bearing exercise High or low impact exercise Howley 2001

6 Recommendations for PA and exercise during pregnancy Independent of pre-pregnancy PA, healthy pregnant women should accumulate at least 150 minutes per week of moderateintensity aerobic activity, during and after their pregnancy (ACOG 2002; 2008 PA Guidelines for Americans; SOGC 2003; RCOG 2006; SMA 2002; Health directorate 2013) Only around 15% of pregnant women follow current exercise guidelines during pregnancy (Gjestland et al 2012; Evenson et al 2004; Petersen et al 2005).

7 Birth weight is forever influence of the in utero environment on postnatal growth Being born too small or too big?

8 Physical activity and fetal growth Leisure time physical activity (LTPA) may reduce the risk of many complications of pregnancy a modifiable factor contributing to birth weight? Abnormal fetal growth and fetal growth restrictions in particular, have been linked to diabetes and cardiovascular conditions in later life.

9 Maternal Exercise and Birth Weight Maternal exercise birth weight Clapp et al. 2000; Hatch et al. 1993; Lewis et al. 1988; Magann et al Maternal exercise birth weight Clapp & Capeless 1990; Clapp et al. 1999; Collings et al. 1983; Marques-Sterling et al Maternal exercise have no effect on birth weight Lokey et al. 1991; Rose et al. 1991; Rice & Fort 1991; Kardel & Kase 1998 Limitations: small sample size, retrospective design, confounding A determinant of birth weight?

10 Excessive BW LTPA Mean Birth weight Low BW/ SGA

11 The Norwegian Institute of Public Health Population-based Recruitment: Countrywide since ,723 women 106,981 pregnancies Followed from pregnancy week 17 and until the child is seven years old

12 3 months Prepregnancy Conception Birth Participation rate: 40% FFQ Follow-up rate: 93.6% Q1 Q2 Q3 MBRN

13 Strolling Brisk walking Running, jogging, orienteering Bicycling Fitness center Prenatal aerobic Low impact aerobic High impact aerobic Dancing Skiing Ballgames, netball Swimming Horseback riding Other Never 1-3 t a month 1 pr week 2 pr week 3 pr week How often are you physically active?

14 Never 1-3 t a month 1 pr week 2 pr week 3 pr week Brisk walking Running, jogging, orienteering Bicycling Fitness center Prenatal aerobic Low impact aerobic High impact aerobic Dancing Skiing Ballgames, netball Swimming Horseback riding Other Frequency of Exercise: Never 1-3 times pr month 1-2 times pr week 3-5 times pr week 6 times pr week

15 Strolling Brisk walking Running, jogging, orienteering Bicycling Fitness center Prenatal aerobic Low impact aerobic High impact aerobic Dancing Skiing Ballgames, netball Swimming Horseback riding Other Never 1-3 t a month 1 t pr week 2 pr week 3 pr week How often are you physically active? Validated against ActiReg (accelerometer) in a sub-sample of 112 MoBa participants.

16 EXERCISE LEVELS FROM PRE-PREGNANCY TO WEEK 30 % 100% Non-exercise Irregular Regular 90% 80% 70% 60% 50% 46,4 28,0 31,0 20,4 26,8 40% 28,6 30% 20% 41,0 53,0 10% 24,6 0% Prepregnancy Week 17 Week 30 Owe, Nystad, Bø, SJMSS 2009

17 EXERCISE LEVELS FROM PRE-PREGNANCY TO WEEK 30 % 100% Non-exercise Irregular Regular 90% 80% 70% 60% 50% 40% 30% 20% 10% 46,4 Regular exercise Irregular exercise Non-exercise 28,6 24,6 20,4 28,0 = 3 times per week = 31,0 1-2 times per week = < Once a week 26,8 53,0 41,0 0% Prepregnancy Week 17 Week 30 Owe, Nystad, Bø, SJMSS 2009

18 LTPA and the birth weight range Excessive BW LTPA Mean Birth weight Low BW/ SGA

19 LTPA and the birth weight range LTPA Mean Birth weight Low birth weight

20 Exercise before and during pregnancy and Excessive Birth Weight N=36,869 singleton pregnancies Exercise assessment 3 months pre-pregnancy Pregnancy week 17 Pregnancy week 30 Excessive birth weight = 90 th percentile by parity (n=4033) Nulliparous: 4170 g Multiparous: 4362 g

21 Pre-pregnancy Exercise Nulliparous aor (95%CI)* Multiparous aor (95%CI)* Exercise frequency Never 1-3 t pr month 1-2 t pr week 3 t pr week Ref ( ) 0.86 ( ) 0.85 ( ) Ref ( ) 1.10 ( ) 1.05 ( ) These results are in *Adjusted for maternal age, BMI prepregnancy, smoking status. Owe, Nystad & Bø, Obstet&Gynecol, 2009

22 Exercise in pregnancy week 17 Nulliparous aor (95%CI)* Multiparous aor (95%CI)* Exercise frequency Never 1-3 t pr month 1-2 t pr week 3 t pr week Ref ( ) 0.91 ( ) 0.72 ( ) Ref ( ) 0.95 ( ) 0.90 ( ) *Adjusted for maternal age, BMI prepregnancy, smoking status, preexisting diabetes, hypertension, maternal height, weight change, energy intake Owe, Nystad & Bø, Obstet&Gynecol, 2009

23 Exercise in pregnancy week 30 Exercise frequency Never 1-3 t pr month 1-2 t pr week 3 t pr week Nulliparous aor (95%CI)* ( ) 0.90 ( ) 0.77 ( ) Multiparous aor (95%CI)* ( ) 1.00 ( ) 0.96 ( ) *Adjusted for maternal age, BMI prepregnancy, smoking status, gestational diabetes mellitus, preeclampsia, maternal height, total weight change, energy intake

24 LTPA and the birth weight range LTPA Low BW/ SGA

25 Exercise during pregnancy and Mean Birth weight MoBa (n=43,705) Mean BW= 3677 grams Exercising 5 times per week was associated with a small reduction in mean birth weight (-42g) DNBC (n=79,692) Mean BW= 3575 grams Small reductions in mean birth weight with exercise A strong association between prepregnancy BMI and mean birth weight (+20.3 g) Fleten et al. Obstet & Gynecol Juhl et al. Am J Obstet & Gynecol

26 LTPA and the birth weight range LTPA

27 First Author, Year Exercise during pregnancy and Low BW/ SGA N Outcome Exposure Result Juhl ,692 SGA Hours per week HR=0.87 ( ) Mudd / 596 SGA Insufficient LTPA Meeting LTPA Recs. Gollenberg SGA Physical activity (different domains) No association. RR=0.42 ( ) RR=2.14 ( ) Hegaard <2500 g Sports (hrs) or LTPA No association Kramer & McDonald 2010 (Cochrane Rev): 2 small RCT studies (n=61) on SGA. Results on the growth of the fetus are inconsistent. 27

28 Preterm birth (<37 weeks) n=61,098 Exercise frequency Week 17 aor (95% CI) Week 30 aor* (95% CI) Never 1-3 times per month 1-2 times per week 3-5 times per week 6 times per week Ref ( ) 0.87 ( ) 0.82 ( ) 0.83 ( ) Ref ( ) 0.77 ( ) 0.74 ( ) 0.75 ( ) Post-term birth(>42 weeks) 1-2 times per week 1.14 ( ) 1.11 ( ) 3-5 times per week 1.15 ( ) No difference in mean gestational length by exercise levels during pregnancy. Owe et al Med Sci Sports Exerc.

29 Summary: Exercise during pregnancy and Birth weight Exercise during pregnancy but not pre-pregnancy is associated with a reduced probability of giving birth to newborns with excessive birth weights Exercises performed in week 30 did not have a different impact on excessive birth weight compared to week 17 Exercise during pregnancy are not associated with mean birth weight A possible reduced risk for Small-for-gestationalage/ low birth weight babies in low risk populations 29

30 Remaining Questions What is the optimal dose of LTPA? Frequency, duration, intensity? Aerobic vs. resistance training Other modes of physical activity? When should LTPA be undertaken? What are the biological mechanisms in play? What are the long-term effects on child s health?

31 Acknowledgement Kari Bø, Professor, Norwegian School of Sport Sciences Wenche Nystad, PhD, Norwegian Institute of Public Health Hein Stigum, PhD, Norwegian Institute of Public Health Rolv Skjærven, Professor, Norwegian Institute of Public Health

32 THANK YOU!