It would be advisable to speak with a medical malpractice attorney.  Medical malpractice is based on negligence.  Negligence is the failure to exercise due care (that degree of care in this case that a reasonable OBGYN in the community would have exercised under the same or similar circumstances to prevent foreseeable harm).  The current MRI report  will  provide evidence of the negligence of the OBGYN.   Prior to filing  a lawsuit, it may be possible to settle the case with the insurance carriers for the doctor and the hospital where you had the C-section.  If you have surgery to have the metallic object removed, you should obtain the medical bills, medical reports, and documentation of any wage loss.  You  should also include medical bills in the past for determining the cause of your pain if it is possible to document this.  Compensation for medical bills is straight reimbursement.  Compensation for wage loss is straight reimbursement.  The medical reports will document the nature and extent of your injury and will be used to determine compensation for pain and suffering.  Compensation for pain and suffering is an amount in addition to the medical bills.  It would be advisable to have the surgery to remove the metallic object before trying to settle the case in order to have the total medical bills, total wage loss and the medical reports documenting the surgery in addition to the MRI report.  If you are dissatisfied with settlement offers from the insurance carriers for the doctor and/or hospital, reject the settlement offers and file your lawsuit for negligence against the party or parties with whom the case has not been settled.  If the case is settled with all parties, NO lawsuit is filed.  If the case is NOT settled with a party, that party would be named as a defendant in your lawsuit for negligence.  You will need to file your lawsuit for negligence prior to the expiration of the applicable statute of limitations or you will lose your rights forever in the matter.