Change in brain size during and after pregnancy: study in healthy women and women with preeclampsia.
OBJECTIVE
Qualitative decreases in maternal brain size have been observed late in pregnancy. The aim of this study was to quantitatively evaluate changes to the maternal brain during and after healthy pregnancy and to compare these changes with those observed in cases of preeclampsia.


METHODS
Three-dimensional T1-weighted MR volume images were obtained in nine healthy participants before and after delivery. Additional images were obtained in some of these participants before pregnancy, during pregnancy, and within 52 weeks after delivery. Five women with preeclampsia were examined before delivery and 6 weeks after delivery. Three of these patients were examined within 52 weeks after delivery. Images were registered, and both brain and ventricular volumes were calculated by using a semiautomated computer program.


RESULTS
Both the healthy and preeclamptic groups had a reduction in brain size during pregnancy that was maximal at term and that reversed by 6 months after delivery. The ventricular size showed a corresponding increase in size during pregnancy and a decrease in size after delivery. In the preeclamptic patients, brain size was significantly smaller (P =.05) than in healthy participants, both before and after delivery.


CONCLUSIONS
The brain decreases in size during pregnancy and increases in size after delivery. The changes follow a consistent time course in each woman. The mechanism and physiologic importance of these findings are speculative at the present time.
Oatridge
Angela
A
Robert Steiner Magnetic Resonance Unit, Clinical Sciences Centre, Imperial College School of Medicine, Hammersmith Hospital, Du Cane Road, London W12 0HS, England.
Holdcroft
Anita
A
Saeed
Nadeem
N
Hajnal
Joseph V
JV
Puri
Basant K
BK
Fusi
Luca
L
Bydder
Graeme M
GM
D000328:Adult; D001921:Brain / Q000473:pathology*; D005260:Female; D005865:Gestational Age; D006801:Humans; D009929:Organ Size / Q000502:physiology; D049590:Postpartum Period / Q000502:physiology; D011225:Pre-Eclampsia / Q000175:diagnosis* / Q000473:pathology; D011247:Pregnancy / Q000502:physiology*; D012016:Reference Values