Brief Answer:
Various causes

Detailed Answer:
Hi dear,
I have gone through your question and understand your concerns.
By bladder, I hope you mean the urinary bladder.
Non visualization of the urinary bladder of the fetus at 14 weeks gestation can be due to various reasons like:
1. Bladder not filled with urine at the time of examination.
2. Obstruction in both the ureters (which are the tubes carrying urine from the kidneys to the urinary bladder.
3. Congenital absence of bladder
4. Absence of anterior wall of the bladder
5. Urogenital tract malformation.
I will suggest you to get a repeat scan for a half hour duration at least to give the normal bladder time to fill up with urine.
If not visualized even in half hour, then you should get a detailed anomaly scan by a fetal medicine specialist to look for the above mentioned anomalies.
Hope you found the answer helpful.
Regards
Dr Deepti Verma
OBGYN
Maternal and fetal medicine specialist

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