The darkening of the neck during pregnancy is usually a normal physiological phenomenon, generally related to the increase in local pigmentation and hyperpigmentation. During pregnancy, due to changes in hormone levels in the body, estrogen and progesterone increase, which will make the melanocyte activity in the body, melanin secretion will increase, so it is easy to lead to the phenomenon of skin pigmentation, so there will be a black neck, there is usually also the phenomenon of facial skin pigmentation, nipple areola color will also become darker. If there are no other abnormal symptoms, there is usually no need to worry too much about the darkening of the neck during pregnancy, and it will gradually improve after the end of the pregnancy, without special treatment. However, if there are abnormal symptoms, you must go to the regular hospital in time, to clarify the specific causes, and then targeted treatment, so as not to delay the condition.