Physical activity, sedentary behaviour and fetal macrosomia in uncomplicated pregnancies: a prospective cohort study.

OBJECTIVE: to explore maternal energy balance, incorporating free living physical activity and sedentary behaviour, in uncomplicated pregnancies at risk of macrosomia. METHODS: a parallel-group cross-sectional analysis was conducted in healthy pregnant women predicted to deliver infants weighing ≥ 4000 g (study group) or < 4000 g (control group). Women were recruited in a 1:1 ratio from antenatal clinics in Northern Ireland. Women wore a SenseWear(®) Body Media Pro3 physical activity armband and completed a food diary for four consecutive days in the third trimester. Physical activity was measured in Metabolic Equivalent of Tasks (METs) where 1 MET = 1 kcal per kilogram of body weight per hour. Analysis of covariance (ANCOVA) was employed using the General Linear Model to adjust for potential confounders. FINDINGS: of the 112 women recruited, 100 complete datasets were available for analysis. There was no significant difference in energy balance between the two groups. Intensity of free living physical activity (average METs) of women predicted to deliver macrosomic infants (n = 50) was significantly lower than that of women in the control group (n = 50) (1.3 (0.2) METs (mean, standard deviation) versus 1.2 (0.2) METs; difference in means -0.1 METs (95% confidence interval: -0.19, -0.01); p = 0.021). Women predicted to deliver macrosomic infants also spent significantly more time in sedentary behaviour (≤ 1 MET) than the control group (16.1 (2.8) hours versus 13.8 (4.3) hours; 2.0 hours (0.3, 3.7), p = 0.020). KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: although there was no association between predicted fetal macrosomia and energy balance, those women predicted to deliver a macrosomic infant exhibited increased sedentary behaviour and reduced physical activity in the third trimester of pregnancy. Professionals caring for women during pregnancy have an important role in promoting and supporting more active lifestyles amongst women who are predicted to deliver a macrosomic infant given the known associated risks.

Women's perceptions and experiences of fetal macrosomia.

OBJECTIVE: to explore women's perceptions and experiences of pregnancy and childbirth following birth of a macrosomic infant (birth weight ≥4000g). METHODS: a qualitative design utilising interviews conducted 13-19 weeks post partum in women's homes. The study was conducted in one Health and Social Care Trust in Northern Ireland between January and September 2010. Participants were identified from a larger cohort of women recruited to a prospective study exploring the impact of physical activity and nutrition on macrosomia. Eleven women who delivered macrosomic infants participated in this phase of the study. FINDINGS: four overarching themes emerged: preparation for delivery; physical and emotional impact of macrosomia; professional relations and perceptions of macrosomia. Findings highlighted the importance of communication with health professionals in relation to both prediction of macrosomia and decision making about childbirth, and offers further understanding into the physical and emotional impact of having a macrosomic infant on women. Furthermore, there was evidence that beliefs and perceptions relating to macrosomia may influence birth experiences and uptake of health promotion messages. KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: this study provides important insight into women's experiences of macrosomia throughout the perinatal period and how they were influenced by previous birth experiences, professional relations and personal perceptions and beliefs about macrosomia. Pregnant women at risk of having a macrosomic infant may require extra support throughout the antenatal period continuing into the postnatal period. Support needs to be tailored to the woman's information needs, with time allocated to explore previous birth experiences, beliefs about macrosomia and options for childbirth.