Will losing weight lead to missed menstruation affect pregnancy

Losing weight can lead to missed menstruation, which may affect pregnancy and should be determined based on specific reasons. Amenorrhea caused by excessive dieting or vigorous exercise may interfere with ovulation function, while short-term endocrine disorders are usually reversible. When body weight rapidly decreases or body fat percentage is too low, the body will activate self-protection mechanisms, inhibit hypothalamic pituitary ovarian axis function, and lead to insufficient secretion of gonadotropins. In this case, the ovaries stop ovulating, and the endometrium cannot thicken and shed normally, resulting in secondary amenorrhea. Commonly seen in women who adopt extreme diets or have daily calorie intake consistently below their basal metabolic needs, accompanied by symptoms such as fatigue and hair loss. It is recommended to gradually restore a balanced diet, increase the intake of high-quality protein and healthy fats, and if necessary, use estrogen and progesterone cycle therapy under the guidance of a doctor. In rare cases, menstrual irregularities may be caused by diseases such as polycystic ovary syndrome and thyroid dysfunction, and are not directly related to weight loss behavior. This type of disease itself can lead to ovulation disorders and an increased risk of infertility, and requires a clear diagnosis through six hormone tests, ultrasound, and other methods. If amenorrhea lasts for more than three months or pregnancy preparation for one year is unsuccessful, one should promptly go to the reproductive medicine department to investigate pathological factors such as premature ovarian failure and hyperprolactinemia. During the preconception period, it is recommended to maintain a healthy BMI range of 18.5-23.9 and avoid losing more than 5% of body weight per month. You can engage in 150 minutes of moderate intensity aerobic exercise combined with strength training per week, with priority given to low impact activities such as jogging and swimming. Daily intake of no less than 1200 calories, ensuring sufficient intake of nutrients such as iron, zinc, and vitamin E. Recording the basal body temperature curve helps to assess ovulation recovery, and if necessary, consultation with the nutrition department and obstetrics and gynecology department can be sought for joint intervention.