”Weight loss” is a constant topic for every woman. Being overweight and obese does not only cause you to lose your looks, but more importantly, it makes your reproductive health face a lot of difficulties. In fertility centers, doctors have a hard time dealing with fat girls who are ready to undergo IVF treatment. I really don’t want to offend these already physically and mentally exhausted fertility patients, but the outcome of the treatment is worrisome. Nowadays, the relationship between weight and IVF outcomes is of great concern. 1. Our assessment of overweight or obesity In daily life, people often use weight to measure the fatness of a person. In contrast, in medical assessment, body mass index is now mainly used to assess your weight. Body mass index (BMI) = weight (kg) ÷ height (m) squared (kg/m2). For example, if a person’s height is 1.75 m and weight is 70 kg, her BMI = 70 ÷ (1.75 × 1.75) = 22.86. BMI takes into account both weight and height, is simple and practical, and can reflect general overweight and obesity, so it is more accurate than simply determining by weight when assessing the risk of some diseases. At present, referring to the Chinese standard, if your BMI is over 24, you are overweight; if BMI is over 28, you are obese. Some women’s weight and BMI are not significantly higher, but the fat is concentrated in the waist and abdomen, the small stomach bulging. This kind of “centripetal obesity” body shape, in fact, has a considerable impact on ovulation. 2, overweight and obesity is indeed related to the outcome of IVF Obesity on female reproductive function damage is increasingly concerned, people have been aware that overweight and obesity can increase the chances of ovulation disorders, obesity with insulin resistance, may increase the chances of recurrent miscarriage. Although there is a lack of very strong medical evidence, many studies have found that being overweight or obese can increase the rate of IVF treatment cycle cancellation, increase the dosage of ovulation-promoting drugs, reduce the pregnancy rate, increase the miscarriage rate, elevate the incidence of obstetric complications such as gestational diabetes and pre-eclampsia, and reduce the chances of patients having full-term healthy babies. 3, overweight and obesity reproductive harm mechanism Now you kind of believe that overweight and obesity are related, right? Why? What are the other disadvantages? (1) treatment cost increase: if you want to achieve the same ovulation effect of normal weight people, need to spend more money and time. This is because being overweight and obese decreases ovarian responsiveness to drugs, especially in patients with hyperinsulinemic signs and hyperandrogenemic signs; increases body surface area, resulting in inadequate metabolism of hormones in the body, especially FSH and estrogen, and increased androgen levels. In vitro studies in both animals and humans have found that the quality and developmental potential of eggs are impaired in obese individuals. (2) It may be related to obesity impairing endometrial tolerance, the exact mechanism of which is uncertain. Studies have found that obese patients who receive eggs from healthy donors continue to have lower pregnancy rates and higher miscarriage rates, suggesting that the endocrine disruption background of obesity may affect the endometrial receptivity to embryos, resulting in poor reproductive outcomes in IVF. (3) Obesity reduces the chances of having a full-term healthy baby. Obesity increases the risk of congenital malformations in the fetus, mainly due to metabolic disorders such as insulin resistance and hyperlipidemia, which reduce the utilization of effective folic acid values. Obesity also increases the risk of prematurity, macrosomia, and perinatal death. In a study of 56,556 singleton and 23,804 twin children born from IVF in the United States from 2008-2010, it was found that the percentage of risk of prematurity was significantly higher if the mother’s BMI was >30. (4) Obesity brings patients with pregnancy and childbirth harm is not small. Compared with women with normal BMI, obesity increases the risk of complications such as diabetes, hypertension, placental abruption and thromboembolic disease during pregnancy by 2 to 3 times; obesity also increases the risk of obstructed labor, emergency cesarean section, intraoperative and postoperative bleeding, postpartum fat liquefaction, and poor prognosis of wound infection in pregnant women. (5) Recent studies have also found that maternal obesity and metabolic disorders also have a negative impact on the health of the child in adulthood. Both paternal and maternal obesity interfere with offspring epigenetic expression and intrauterine embryonic developmental gene reprogramming, and these basic studies, are sounding alarm bells to humanity.