Dr Shazia Sobia will replace Alizeh Iqbal Haider, the spokesperson for Pakistan Peoples Party chairperson Bilawal Bhutto Zardari, who resigned from her National Assembly seat last week.
Alizeh, who was elected on the reserved seat for women on a PPP ticket from Sindh, recently tendered her resignation, citing personal reasons, paving way for Dr Sobia, who hails from Pano Aqil of Sukkur district.
Under the rules, all parties taking part in general elections must submit their list carrying nominees on reserved seats with the Election Commission of Pakistan before the polls.
The reserved seats are allocated to parties from the list in descending order in proportion to the general seats they win in the general elections.
Once a reserve seat falls vacant, the next person in the list from that party is notified by the ECP as a lawmaker.