Brief answer...there can be various reasons for a swelling like this.
Detailed answer...
Hello,
Thanks for the query.
I have read your query and understand your concern very well.
There can be numerous reasons for a mass like this.
It could be a lipoma,if it is soft and movable.
It could be a incisional hernia if mass bulges out on coughing and has appeared after your C section .
It could be a fibrous collection of blood,if it has developed after C section.
It could be sebaceous cyst.
It can be a colon cancer as you have a family history of this.
It can be something originating from kidney.
There is still a long list of other possibilities.
You need to consult a doctor for visual inspection,examination and possible investigations like ultrasound abdomen and an abdominal CT scan.
it is better not to delay and consult a doctor as early as possible.
I hope it helps,however you may revert to me or any further query.
Best of luck
Thanks

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