Physical activity during pregnancy and its effects on fetal parameters in the second trimester

The physical activity (PA) during pregnancy still remains controversial due to the risk and protective effects on the fetal parameters (cephalic perimeter, abdominal perimeter, femur length and fetal weight). The American College of Sports Medicine (ACSM) recommends that pregnant women do, at least, 150 weekly minutes of moderate PA during a week (WK). This study aimed to (1) verify the relation between the accomplishment of ACSM guidelines PA and the maternal individual characteristics; (2) verify the relation between accomplishment of these guidelines and the fetal parameters in the second trimester. Prospective study was conducted at Hospital S. João, with a sample of 137 pregnant women. Socio-demographic characteristics and lifestyle factors were assessed via questionnaire. PA was assessed by accelerometry (used for 7 consecutive days) in the second trimester (20–22 weeks). The fetal parameters were assessed by ultrasound between the 20th and 22nd gestational week, always by the same medical. No relation was found between the participants’ individual characteristics and the accomplishment of the ACSM’s recommendations, with p-value for all the variables being >0.05. There is no difference between the fetal parameters in the second trimester of the women who follow the recommendations (p>0.05). The pregnant women’s individual characteristics were not related with the accomplishment of the ACSM’s recommendations. Any relation between the recommendations accomplishment and the fetal parameters in the second trimester was not found and no negative influence was found in the same parameters.