Survey study, 2015
Does a brain chemical involved in mood change during the menstrual cycle?
In women with natural cycles, GABA (a calming brain chemical) increased at ovulation. In women on hormonal contraceptives, GABA levels did not change between pill phases. GABA levels were not linked to premenstrual symptom severity.
What they did
Women had MRI scans measuring GABA (a brain chemical) in the prefrontal region at different cycle phases: 10 women with natural cycles had three scans per cycle and 21 women taking hormonal contraceptives had two scans. Researchers also collected hormone blood tests and asked women to track symptoms.
What they found
GABA concentration significantly increased at ovulation in the natural cycle group. The contraceptive group showed no phase differences in GABA. GABA did not correlate with hormone levels or premenstrual symptoms.
What it means for you
A brain chemical varies across the menstrual cycle in women with natural cycles, but this change doesn't predict how severe premenstrual symptoms will be. The natural cycle group was very small (only 10 women), making conclusions less reliable.
10
Women with natural cycles
21
Women on hormonal contraceptives
3
MRI scans per cycle in natural cycle group
About the study
- Original title
- Prefrontal GABA concentration changes in women-Influence of menstrual cycle phase, hormonal contraceptive use, and correlation with premenstrual symptoms
- Authors
- De Bondt T, De Belder F, Vanhevel F et al.
- Journal
- Brain research
- Year
- 2015
- Study design
- Survey study
- Participants
- 21
- What was tested
- Observation of natural menstrual cycle and hormonal contraceptive use
- Read the paper
- doi.org/10.1016/j.brainres.2014.11.051
Topics
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