Cognitive impairment during pregnancy: a meta-analysis

Sasha J Davies, Jarrad AG Lum, Helen Skouteris, Linda K Byrne and Melissa J Hayden
Med J Aust 2018; 208 (1): . || doi: 10.5694/mja17.00131
Published online: 15 January 2018


Objectives: Many women report declines in cognitive function during pregnancy, but attempts to empirically evaluate such changes have yielded inconsistent results. We aimed to determine whether pregnancy is associated with objective declines in cognitive functioning, and to assess the progression of any declines during pregnancy.

Study design: We undertook a meta-analysis, applying a random effects model, of 20 studies that have reported quantitative relationships between pregnancy and changes in cognition.

Data sources: Full text articles indexed by Cumulative Index to Nursing and Allied Health Literature (CINAHL) Complete, MEDLINE Complete, and PsychINFO.

Data synthesis: The 20 studies assessed included 709 pregnant women and 521 non-pregnant women. Overall cognitive functioning was poorer in pregnant women than in non-pregnant women (standardised mean difference [SMD], 0.52 [95% CI, 0.07–0.97]; P = 0.025). Analysis of cross-sectional studies found that general cognitive functioning (SMD, 1.28 [95% CI 0.26–2.30]; P = 0.014), memory (SMD, 1.47 [95% CI, 0.27–2.68]; P = 0.017), and executive functioning (SMD, 0.46 [95% CI, 0.03–0.89]; P = 0.036) were significantly reduced during the third trimester of pregnancy (compared with control women), but not during the first two trimesters. Longitudinal studies found declines between the first and second trimesters in general cognitive functioning (SMD, 0.29 [95% CI, 0.08–0.50]; P = 0.006) and memory (SMD, 0.33 [95% CI, 0.12–0.54]; P = 0.002), but not between the second and third trimesters.

Conclusions: General cognitive functioning, memory, and executive functioning were significantly poorer in pregnant than in control women, particularly during the third trimester. The differences primarily develop during the first trimester, and are consistent with recent findings of long term reductions in brain grey matter volume during pregnancy. The impact of these effects on the quality of life and everyday functioning of pregnant women requires further investigation.

  • Deakin University, Melbourne, VIC


Competing interests:

No relevant disclosures.

  • 1. Brett M, Baxendale S. Motherhood and memory: a review. Psychoneuroendocrinology 2001; 26: 339-362.
  • 2. Brindle PM, Brown MW, Brown J, et al. Objective and subjective memory impairment in pregnancy. Psychol Med 1991; 21: 647-653.
  • 3. Casey P, Huntsdale C, Angus G, Janes C. Memory in pregnancy. II. Implicit, incidental, explicit, semantic, short-term, working and prospective memory in primigravid, multigravid and postpartum women. J Psychosom Obstet Gynaecol 1999; 20: 158-164.
  • 4. Poser CM, Kassirer MR, Peyser JM. Benign encephalopathy of pregnancy: preliminary clinical observations. Acta Neurol Scand 1986; 73: 39-43.
  • 5. Parsons C, Redman S. Self-reported cognitive change during pregnancy. Aust J Adv Nurs 1991; 9: 20-29.
  • 6. Christensen H, Poyser C, Pollitt P, Cubis J. Pregnancy may confer a selective cognitive advantage. J Reprod Infant Psychol 1999; 17: 7-25.
  • 7. de Groot RHM, Hornstra G, Roozendaal N, Jolles J. Memory performance, but not information processing speed, may be reduced during early pregnancy. J Clin Exp Neuropsychol 2003; 25: 482-488.
  • 8. Glynn LM. Giving birth to a new brain: hormone exposures of pregnancy influence human memory. Psychoneuroendocrinology 2010; 35: 1148-1155.
  • 9. Parsons TD, Thompson E, Buckwalter DK, et al. Pregnancy history and cognition during and after pregnancy. Int J Neurosci 2004; 114: 1099-1110.
  • 10. Raz S. Behavioral and neural correlates of cognitive-affective function during late pregnancy: an event-related potentials study. Behav Brain Res 2014; 267: 17-25.
  • 11. Sharp K, Brindle PM, Brown MW, Turner GM. Memory loss during pregnancy. Br J Obstet Gynaecol 1993; 100: 209-215.
  • 12. Farrar D, Tuffnell D, Neill J, et al. Assessment of cognitive function across pregnancy using CANTAB: a longitudinal study. Brain Cogn 2014; 84: 76-84.
  • 13. Logan DM, Hill KR, Jones R, et al. How do memory and attention change with pregnancy and childbirth? A controlled longitudinal examination of neuropsychological functioning in pregnant and postpartum women. J Clin Exp Neuropsychol 2014; 36: 528-539.
  • 14. Crawley R, Grant S, Hinshaw K. Cognitive changes in pregnancy: mild decline or societal stereotype? Appl Cogn Psychol 2008; 22: 1142-1162.
  • 15. Cuttler C, Graf P, Pawluski JL, Galea LAM. Everyday life memory deficits in pregnant women. Can J Exp Psychol 2011; 65: 27-37.
  • 16. Henry JD, Rendell PG. A review of the impact of pregnancy on memory function. J Clin Exp Neuropsychol 2007; 29: 793-803.
  • 17. Wells GA, Shea B, O’Connell D, et al. The Newcastle–Ottawa Scale (NOS) for assessing the quality of nonrandomised studies in meta-analyses. The Ottawa Hospital Research Institute [website]. 2003. (viewed Oct 2017).
  • 18. Anderson MV, Rutherford MD. Recognition of novel faces after single exposure is enhanced during pregnancy. Evol Psychol 2011; 9: 47-60.
  • 19. Condon JT, Derham, D, Kneebone AC. Cognitive functioning during pregnancy: a controlled investigation using psychometric testing. Int J Prenatal Perinatal Psychol Med 1991; 60: 199-212.
  • 20. Harris ND, Deary IJ, Harris MB, et al. Peripartal cognitive impairment: secondary to depression? Br J Health Psychol 1996; 1: 127-136.
  • 21. Henry JF, Sherwin BB. Hormones and cognitive functioning during late pregnancy and postpartum: a longitudinal study. Behav Neurosci 2012; 126: 73-85.
  • 22. Keenan PA, Yaldoo DT, Stress ME, et al. Explicit memory in pregnant women. Am J Obstet Gynecol 1998; 179: 731-737.
  • 23. McDowall J, Moriarty R. Implicit and explicit memory in pregnant women: an analysis of data-driven and conceptually driven processes. Q J Exp Psychol A 2000; 53: 729-740.
  • 24. Onyper SV, Searleman A, Thacher PV, et al. Executive functioning and general cognitive ability in pregnant women and matched controls. J Clin Exp Neuropsychol 2010; 32: 986-995.
  • 25. Shetty DN, Pathak SS. Correlation between plasma neurotransmitters and memory loss in pregnancy. J Reprod Med 2002; 47: 494-496.
  • 26. Vanston CM, Watson NV. Selective and persistent effect of foetal sex on cognition in pregnant women. Neuroreport 2005; 16: 779-782.
  • 27. Wilson DL, Barnes M, Ellett L, et al. Compromised verbal episodic memory with intact visual and procedural memory during pregnancy. J Clin Exp Neuropsychol 2011; 33: 680-691.
  • 28. Wilson DL, Barnes M, Ellett L, et al. Reduced verbal memory retention is unrelated to sleep disturbance during pregnancy. Aust Psychologist 2013; 48: 196-208.
  • 29. Crawley RA, Dennison K, Carter C. Cognition in pregnancy and the first year post-partum. Psychol Psychother 2003; 76: 69-84.
  • 30. Casey P. A longitudinal study of cognitive performance during pregnancy and new motherhood. Arch Womens Ment Health 2000; 3: 65-76.
  • 31. Janes C, Casey P, Huntsdale C, Angus G. Memory in pregnancy. I. Subjective experiences and objective assessment of implicit, explicit and working memory in primigravid and primiparous women. J Psychosom Obstet Gynaecol 1999; 20: 80-87.
  • 32. Christensen H, Leach LS, Mackinnon A. Cognition in pregnancy and motherhood: prospective cohort study. Br J Psychiatry 2010; 196: 126-132.
  • 33. de Groot RMH, Vuurman EFPM, Hornstra G, Jolles J. Differences in cognitive performance during pregnancy and early motherhood. Psychol Med 2006; 36: 1023-1032.
  • 34. Hedges LV, Vevea JL. Fixed-and random-effects models in meta-analysis. Psychol Methods 1998; 3: 486.
  • 35. Higgins JP, Thompson SG, Deeks JJ, Altman DG. Measuring inconsistency in meta-analyses. BMJ 2003; 327: 557-560.
  • 36. Hoekzema E, Barba-Müller E, Pozzobon C, et al. Pregnancy leads to long-lasting changes in human brain structure. Nat Neurosci 2017; 20: 287-296.


remove_circle_outline Delete Author
add_circle_outline Add Author

Do you have any competing interests to declare? *

I/we agree to assign copyright to the Medical Journal of Australia and agree to the Conditions of publication *
I/we agree to the Terms of use of the Medical Journal of Australia *
Email me when people comment on this article

Online responses are no longer available. Please refer to our instructions for authors page for more information.