Understanding Post-Ovulation Bleeding: Causes & When to Worry

Question
My wife is in mid of her period cycle, she ovulated on 29th Nov. We had sex on 27th and 28th. She is started getting back pain on 3rd Dec and her vagina is spotting on 4th dec evening and now today morning it started bleeding thin red color blood. We asked doctor she asked to wait for 2 day more if bleeding doesn't stop we will visit doctor. But do you know what could cause the bleeding? She never had mid cycle bleeding and her cycle is of 30 to 33 days. She is due period on 14th Dec.

Answer
Santy
My assumption is that this can be a miscarriage of a chemical pregnancy. This is an unrecognized pregnancy that occurs and ends before the first missed menstrual period. However, if your wife is above 40, this can be the start of the hormonal imbalance that starts to occur around this age.