Domestic mothers preparing for pregnancy are often urged to gain weight by their family elders, but in fact mothers preparing for pregnancy should pay particular attention to weight control. Many researchers at home and abroad have found that the low likelihood of pregnancy is related to obesity, and that obese women have an increased risk of complications during pregnancy even if they become pregnant. Dutch obstetricians and gynecologists have found that body mass index (BMI = weight kg/height cm2) is surprisingly related to the chances of pregnancy, and they believe that obesity is a risk factor for women to stop ovulating. Women who also gain weight suddenly or are obese all the time may also have hormonal imbalances and metabolic disturbances. Endocrine disorders in women with obesity and infertility can manifest as menstrual disorders, amenorrhea, and enlarged ovaries. Further hormone testing is needed to confirm the diagnosis. If not treated in time, it may lead to infertility or miscarriage. Scientific weight management should start before pregnancy. Because being too fat or too thin can affect a woman’s endocrine function and is not conducive to conception. The main measure to lose weight is to control diet, as well as low sugar, low salt, low oil, high fiber diet, etc. Increase physical activity and aim to lose 0.5-1 kg per week with a two-pronged approach of diet and exercise control. Strive to reduce the weight to about than the standard weight. Standard weight = (height cm-70)*0.6, fluctuating around 5kg.