My poor queen

Question
Dear Norman
I've been having cats for some years but a few days before i experienced one of the most horrible events regarding my cats . my white Persian queen Princess was pregnant and about to give birth .we were extremely glad and everything was going ok , but at Tuesday morning when we got up we realized that our queen sounds so dull and awfully pale and feeble ,while she was pregnant for exactly 62 days . we immediately took her to pet hospital and over there we get shocked , as due to X ray it got obvious that all kittens are death! we couldn't believe it as until last night(Monday night) we could see them moving and playing inside their mom's womb , and our queen also was totally healthy .
soon they operate her as her situation was so critical . i had asked them to save her womb at least but after the operation they told me that they didn't have any other choice but spaying her ,as some parts of her womb had been destroyed totally due to the infection caused by the dead kittens . they show us some pictures taken during operation that showed her womb twisted four times ! you see, they told us that the part of the womb that had twisted , had included 2 kittens that died soon after this . then it caused the inflections which led to the death of other 4 kittens and destruction of the womb and mom's serious situation .
they said that this might happened few day before as those 2 kittens had been fetid badly , but it was obvious that other 4 kittens were alive till few hours before .
the condition of my queen also was so bad as inflection has made her so feeble as she can't even walk properly . vets told us that she was so lucky that survived .thank God she's started to recover slowly.
we all are in terrible mood nowadays as we had not expected her to be spayed at the age of 2 and half .I personally can't forget the scene of 6 death kittens that i saw inside the operation room . its a terribly sad fact that she wont be able to give birth any more .we are just furious and frustrated as we can't detect why it happened ,and vets also can't say anything about the main cause of this tragedy .
you see doctor , we were so careful and cautious about her . feeding her in the best way and taking care of her days and nights , we had not expected this to happen at all .having inspected on her every time , i can firmly tell you that till Monday night she had not shown any sign of any problem inside . but , at Tuesday morning she had suddenly changed to a pale dying cat !
can you please tell us why it happened to her ? why her womb had twisted four times !? she had given birth at first time when she was one year old , and her second litter was about 6 months before . however , between her second litter and this one once she got pregnant about 3 months before , and then when an irresponsible vet squeezed her while she was about one month pregnant ,she miscarriage . and immediately after that she got pregnant of this last one . can i regard this soon pregnancy after the miscarriage as a main cause of the recent tragedy ?
i must add also that she used to jump on high niches many time each day . even in last few weeks she enjoyed to do so while she had turned so heavy and big. can this be the main cause? should i prevent her to do so? I'm just so needy to know the cause of the tragedy as i have an other queen and i absolutely don't want to experience something same . we just can't understand why it happened as she had given birth 2 times before without any problem .
let me add finally that she is due to an inbreeding . i mean , her brother had mated with her own mom and this lead to the birth of my queen and four other kittens .however , she's totally healthy and in a reasonable and normal shape .  can i regard that inbreeding as a cause of that event?
Thanks a lot for your precious responds
Soheil from Iran

Answer
Soheil,

I am so sorry for your loss!!!!!!!  At least your white Persian survived the ordeal.

I wish I could give you an answer as to what caused the twisted uterus.  This is not unheard of, but very, very rare.  In truth, I do not believe there was anything you could have done to prevent this unfortunate happenstance.  There is no way one can attribute the twisted uterus to any one incident,, without much speculation.

When things go well, breeding cats can be a rewarding experience.  When things go badly, it can be a nightmare.  So, one must accept the heartbreaks along with the joys.

As far as exercise, the mama cat usually knows how much to do.  It is normal and healthy for pregnant queens to be active and jump to places and back down.  The kittens are well cushioned by the amniotic fluid, and the exercise helps keep everything toned.

Given that she had two healthy litters previously, I would attribute this last as a cruel accident of nature.  I would not attribute it to the inbreeding since she successfully gave birth previously. Cats are very stoical and, if they are not feeling up to par, they often do not show it until things have gotten pretty bad.  So, there was no way of knowing from her behavior that anything was wrong until the fateful Tuesday!!!!!

Please accept my condolences on your loss of the litter and this female for breeding.

Sad regards... Norm.