Experiencing excess saliva production during pregnancy is a common symptom known as ptyalism. It typically starts around the fourth week and can last throughout the first trimester. While the exact cause is unknown, hormonal changes and increased blood flow to the salivary glands are believed to contribute to this condition. Progesterone injections, which are commonly used in certain cases during pregnancy, do not directly affect saliva production. However, it's always best to consult with your healthcare provider for personalized advice and guidance regarding your specific situation. They can provide you with appropriate recommendations or suggest alternative treatments if needed. In the meantime, you may find relief by avoiding triggers such as spicy or acidic foods, practicing good oral hygiene, chewing sugar-free gum, and using mouth rinses recommended by your dentist or doctor.