1. Smoking cigarettes and marijuana should be avoided. They decrease the number of eggs and produce poor egg quality and an increase in egg abnormalities.
2. Plastics should be limited because they are what is termed endocrine disrupting chemicals. Thereby disrupting how the brain and ovaries produce hormones. Drinking should be done by use of a glass, stainless steel or aluminum.
3. Protection against STIs is vital. Sexually transmitted diseases can permanently damage the fallopian tubes and possibly lead to IVF in the future.
4. Processed food is another factor that must be considered. In embryo development studies the more servings of red and processed meat that were ingested during IVF, the greater poor embryo development occurred. Sugars that are involved in these types of foods that are wrapped for example can affect the insulin cycle and impact ovulation.
5. Pay attention to the menstrual cycle as it can be an indicator of high or low the ovarian reserve is. Therefore, it is advised to come off contraception six months before planning to become pregnant.
6. Age consideration is still a prediction of success. Becoming 40 yrs old equates to a chance of pregnancy of approximately 5% each month. A younger age is closer to a 20% chance each month which isa significant difference.
These factors should be considered seriously when planning for a pregnancy.
Ref:
https://www.the-sun.com/health/4092296/pregnancy-test-results-when-take/ 
