She also noticed that her menstrual cycle had become irregular. Heather's parents saw the changes in their daughter. But their question turned up nothing, and they were worried. As a result, the ability to learn and to remember recent events may be hampered. Smoking marijuana can deliver three times more tar than smoking tobacco.
Regular use can lead to chronic bronchitis.
Based on animal and in vitro studies using both human and animal material, its possible that pot may impair the capacity of the white cells to fight invading infection. Marijuana's final insult is to the pituitary gland, which regulates sex hormones. In men, sperm production can drop. And in women, ovulation may be inhibited. By her sophomore year, Heather knew all of the tricks.