That answer is yes according to Dr Green, author of: Dr. Robert Greene’s Perfect Hormone Balance for Pregnancy: A Groundbreaking Plan for Having a Healthy Baby and Feeling Great
He says that:
Keeping a lemon handy at all times and sniffing it when you feel nausea coming on can help curb morning sickness. “The part of our brain that is most directly connected with the nausea center is our sense of smell,” he says.
Just as certain smells make you feel sick during pregnancy, Dr. Greene says the strong, cleansing fragrance of a lemon can rapidly help nausea subside. “If you ignore and don’t correct nausea during the first trimester of pregnancy, that increases the risk of preterm labor and blood pressure problems in the third trimester,” he says.