Medical malpractice is negligence.  Negligence is the failure to exercise due care (that degree of care that a reasonable medical practitioner in the community would have exercised under the same or similar circumstances to prevent foreseeable harm).If the nurse practitioner is an employee of the Ob-Gyn group, the employer is liable for the negligence of the nurse practitioner which occurred in the course and scope of  employment.Prior to filing a lawsuit, it may be possible to settle the case with the malpractice insurance carrier for the Ob-Gyn group.Your wife should obtain her medical bills, medical reports (especially the medical report from the ER) and documentation of any wage loss.  Her claim filed with the malpractice insurance carrier should include these items.Compensation for the medical bills is straight reimbursement.  The medical reports will document the nature and extent of her condition/injury and will be used to determine compensation for pain and suffering which is an amount in addition to the medical bills.  Compensation for wage loss is straight reimbursement.If the case is settled with the malpractice insurance carrier, NO lawsuit is filed.If your wife is dissatisfied with settlement offers from the malpractice insurance carrier, she should reject the settlement offers and file a lawsuit for negligence against the Ob-Gyn group and the nurse practitioner.  Only one lawsuit is filed naming both Ob-Gyn group and the nurse practitioner as defendants.If the case is NOT settled with the malpractice insurance carrier, your wife's lawsuit for negligence must be filed prior to the expiration of the applicable statute of limitations or she will lose her rights forever in the matter.