While La Sirène's Beauty Collagen is a natural Marine Collagen protein with no known serious side effects, it is not recommended during pregnancy. Hormonal changes due to pregnancy may vary from woman to woman, and may naturally result in undesirable changes in the skin, hair and nails. It is advised to refrain from supplement use that is not recommended by a medical doctor throughout the entirety of a pregnancy. La Sirène's Beauty Collagen is safe to consume while breastfeeding once your baby is born, and can help the body recalibrate the condition of your skin, hair and nails as the pregnancy hormones leave your body and begin to return to their normal state.