To an extent. A woman who has experienced a single miscarriage has the same chances of experiencing another miscarriage with her next pregnancy as a woman who has had zero miscarriages. The chances of a miscarriage only increase with two or more experienced miscarriages.

A severely underweight woman (with less than 17 percent body fat) may have irregular ovulation, reducing their odds of conception.

Smoking ages your ovaries and depletes your eggs prematurely.

Causes of implantation failure include  genetic defects, thin endometrium, embryonic defects and endometriosis.

Sufficient follicle stimulating hormone action is also needed for proper sperm production.

Only barrier methods (male condoms and internal condoms) prevent pregnancy and STIs. The rest only protect against pregnancy but not from infections.