| Effect | Decrease |
| Trial Design | Double blind |
| Trial Length | 1-6 months |
| Number of Subjects | 70 |
| Gender | Female |
| Age Range | 18-29, 30-44 |
2g of krill oil (1g twice a day; 18% EPA and 12% DHA) starting 8 days prior to the menstrual cycle for 90 days was able to significantly reduce all symptoms of PMS measured by the first assessment (day 45) with further improvement on day 90 relative to the control group, which was given fish oil