A woman having a BMI of more than 30 will take more months to conceive when compared to a woman having a BMI of 25. That means the probability of having infertility is higher when the BMI is more than 30. The 2nd situation is obese women are more proven to have irregular cycles and they have problems with ovulation. A reduction of obesity to normal means a reduction of BMI from more than 30 to less than 30 will significantly improve the chance of ovulation and they will require less amount of medication and less number of cycles to achieve a pregnancy.
Another aspect of women with obesity is they are more prone to diabetes which is highly prevalent in India and if their families have diabetes, these women will have a higher risk for diabetes. Either it is pre-existing or more prone for another thing called gestational diabetes which can happen during pregnancy. The 3rd aspect is obese women are frequently associated with thyroid dysfunction. The 4th aspect is there is something called metabolic syndrome. That means obese women have a higher chance of hypertension, a higher chance of cholesterol and triglycerides, and they have a long-term risk of cardiovascular disorders.
So, in other words, obese women take a longer time to conceive, have more association with diabetes, have more association with thyroid, have more complications during pregnancy, and also very importantly their long-term health is compromised by a situation called metabolic syndrome.