How red is the eye? Is it pinky red at one side? If so this could be due to allergy eg hayfever, or irritation of some sort. It could also be something called episcleritis which is an inflammation of the blood vessels. It is quite harmless and will go on its own over time.
Does the eye/s feel sore or gritty at all? If so it colud be a dry eye which is common in pregnancy due to the change in hormones. I couldn't wear my contact lenses during this pregnancy and my first pregnancy due to this. I couldn't wear lenses in first tri with second pregnancy but it settled in second and third tris.
Is the eye bright red? If so then this could be a sub conjuctival haemorrhage. This is basically a burst blood vessels, there are several causes. If you've had a cold and been snezzing and/or coughing a lot then that can cause it. If you are constipated and straining to go to toilet (sorry if a bit personal/tmi) this can also be a cause. Yet another cause can be high blood pressure. This is only likely though if it is happening a lot, eg every couple of weeks. However as you are pg no harm getting blood pressure checked if you have a sub conj. haem.
This will clear on its own but depending on severity can take a good week to clear.
Hope this helps.
Take Care,
Caroline
