Final answer:
An antepartum nurse should initiate seizure precautions for pregnant clients at risk of seizures, such as those with preeclampsia, eclampsia, or a known seizure disorder, to manage potential seizures with anticonvulsants like diazepam.
Step-by-step explanation:
An antepartum nurse should initiate seizure precautions for clients who have conditions that increase the risk of seizures or for those who have a history of seizure disorders. During pregnancy, conditions such as preeclampsia or eclampsia can significantly heighten the risk of seizures. Therefore, if a pregnant patient shows signs of these conditions or has a known seizure disorder, it is crucial to be prepared with anticonvulsants, like diazepam, to manage potential seizures as they can improve the long term prognosis by reducing the risk of brain damage to the patient and potentially the fetus.