Purpose: Studies have shown that absolute intensity of physical activity is associated with reduced risk of preeclampsia. This analysis was performed to examine whether relative intensity may also be related to preeclampsia risk.
Methods: Using data from a case-control study conducted from 1998 to 2002, the authors assessed the relation between perceived exertion (i.e., relative intensity) during usual recreational physical activity in the year before pregnancy and risk of preeclampsia. In a structured interview conducted during postpartum hospitalization, 244 preeclampsia cases and 470 normotensive controls provided details on their recreational physical activities in the year before pregnancy.
Results: Participants who reported feeling very strenuous to maximal exertion during usual prepregnancy physical activity were 78% less likely to have developed preeclampsia than those who reported negligible or minimal exertion (adjusted odds ratio 0.22, 95% confidence interval 0.11-0.44). A significant trend was noted of decreased preeclampsia risk with increased perceived exertion (P < 0.001). This association was independent of prepregnancy adiposity, and was also apparent among the subset of participants who did not meet physical activity guidelines in the year before pregnancy.
Conclusions: In this study, relative intensity of recreational physical activity performed during the year before pregnancy was associated with a decreased risk of preeclampsia.