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שלום

I am 38.5

I had 2 miscarriages about 2 years ago about 4 months apart at 6 (no fetus) ,and 9 (heart beat seen) weeks (D&C - no pathology taken).
Then I have given birth to a boy a year ago.
We did not find any reason for the m/c.
I had another missed miscarriage a month ago, week 8, heart beat seen at week 7.2 , pathology came back as male trisomy 22.

I wonder:
1. Is Trisomy 22 the likely reason for the miscarriage as I read that some babies are born with this trisomy.
2. Both me and my husband think that we probably had abnormal fetuses in all 3 m/c. Can it be that we have a problem that causing those chromosome abnormalities to reoccur all the time? (Our Karyotype and genetic tests are fine).
3. With your experience should we be worried and think about PGD (time is pressing because of my age) or should we try more.
4. I had my bleeding 4 weeks exactly after the D&C (very light for 2 days only). And saw an LH surge 8 days after the start of the bleeding (I normally had a 29 days cycle with surge at day 13). Can that be ovulation? Is it possible to ovulate twice a month as now at day 10 I start to feel again that I am before ovulation.

Thanks