Prenatal Vitamins containing folic acid can prevent brain and spinal cord defect (Neural tube defect) Because the brain and spine begins forming before your pregnancy test is positive you should start taking folic acid 2-3 months before attempting pregnancy.

overweight or obesity can reduce chance of pregnancy by interfering with normal ovulation being obese or overweight during pregnancy can increase risk of hypertension and diabetes of pregnancy. It also increase chance of C-section.

If you have a medical condition such as blood pressure, diabetes, lupus or seizure the medication you take to help you in this condition could be harmful to the developing fetus. Reducing the dosage of your medication or changing your medication is safer for pregnancy and can help avoid the risk to the fetus.
Go for routine baseline Blood check-up. It is to rule out amemia diabetes and to know about your Rubella IgG antibodies