During pregnancy, many women complain that they feel more distractible, more forgetful or less sharp than before pregnancy. A few years ago, we reviewed a study which demonstrated that performance on tests of spatial recognition memory (SRM) were adversely affected by pregnancy. Other aspects of executive function were unaffected.
A recent study assessed working memory ( WM) in pregnant women at 34-36 weeks of gestation (n = 28) and compared their performance to age- and education-matched non-pregnant controls (n = 26). The researchers found that pregnant women had more problems in working memory than nonpregnant women; however, working memory deficits were observed only in women with depressive symptoms during pregnancy. (The earlier study from Farrar et al did not observe an association between cognitive deficits and depression or anxiety.) No significant differences were observed on tests of other cognitive functions.
They also observed that serum estradiol concentrations, along with severity of depressive symptoms but not sleep disruption, significantly predicted variation in working memory scores. Consistent with others studies of estradiol and WM in other settings, higher estradiol levels were associated with better WM, whereas higher levels of depressive symptoms predicted poorer WM.
So this study suggests that while memory disturbance during pregnancy might not be as common as some believe, it is observed more frequently among women experiencing depression during pregnancy. This study also suggests that, at least for non-depressed women, the higher estradiol levels observed during pregnancy may actually improve cognitive functioning.
Ruta Nonacs, MD PhD
Hampson E, Phillips SD, Duff-Canning SJ, Evans KL, Merrill M, Pinsonneault JK, Sadée W, Soares CN, Steiner M.
Horm Behav. 2015 Aug;74:218-27.