Taking aspirin

Have started on aspirin since Week 16/18 (don't exactly remember) on gynae's instruction due to having twins. I do remember gynae mentioned that usually there should be some test to show if there is high risk of high blood pressure but as multiple pregnancy has higher risk, we started anyway. Nurse did mention usually my gynae will stop the aspirin 1 month b4 delivery, hence i don't overbuy. The instruction is to take before sleep. No side effects for me though.