What can be the reason for IUFD?

Hi doctor,

This is about my wife, who had unfortunate IUFD, cardiomyopathy and DIC. She had an absolute normal pregnancy till 9th month. She had no BP, diabetes or other issues throughout and even today. Only issue, she has is migraine and for which she takes Diclogesic. So, it happened on a day of routine checkup when Doppler scan released little less fluid (7.3) around baby and placental calcification that doctor advised C-section. She was empty stomach after breakfast from morning till evening and developed a migraine, which is normal as she had this condition before as well. Gradually, she became breathless, tachycardia and her pulse rate shoot up to 170 or 180 while saturation was around 99 %.

While doctors were trying to stabilize her, they could not track the baby's heartbeat and then she had other above specified conditions. So, I am looking back what could have gone wrong. Below are the few things that I need your help in understanding. We have a son already who is O negative and my wife is A negative. Anti-D was given only in the 28th week of pregnancy and not after CS delivery, which is fine I guess. But, she was not given an Anti-D this time, but stillbirth (boy) was O positive. Hence, wondering if this was one factor if not for IUFD (as all scans till 9th month were normal) at least for DIC afterward? Secondly, to stabilize her migraine when she was posted for C-section she was given Dynapar 75 mg, which looks like another factor that could have caused ductus arteriosus to close before time and IUFD. Please clarify.

Thank you doctor,

Do you think Anti-D not being given can probably cause DIC? Because after IUFD, mother and baby blood contact happens and in this case little blood clot was also found after placenta biopsy. Secondly, after the baby was out, discharge summary points out adequate fluid. So, I do not really think that to be the cause of IUFD. In the last scan, the amount of fluid was 7.3 and the baby was 7 lbs. About Diclofenac, as I could read various studies on the internet, it is generally not advised and even if it is given it should be in accordance with mother weight. In our case, 75 mg was given.