hi. During pregnancy the immune system usualy is a bit weaker, so it's not uncommon to get a cough. If the cough doesnt persist for a long time you can use home remedies such as gargling lukewarm salt water solution or drinking warm tea can help. Also boosting the imune system with enough sleep, good hydration and foods rich in vitamin c such as kiwis or oranges helps. If there is other symptoms such as fever or discoloured mucus or chest pain occur I would see a doctor.