Hi, It depends upon which type of laxative is used. Mild laxatives like milk of magnesia or Metamucil are considered to be safe during pregnancy. However a stronger purgative like castor oil may cause uterine contractions and thus there is a risk of miscarriage. Overuse of laxatives can cause diarrhea diarrhea, leading to fluid loss, electrolyte imbalances and can reduce the amount of nutrients that are absorbed into the body. It can also affect the absorptions of any medications you might be taking. In view of the above I advise you to try the natural methods of relieving constipation like increased intake of fruits, vegetables, oral fluids and physical activity. Hope I have answered your query. Let me know if I can assist you further. Take care Regards, Dr. Mohammed Taher Ali