A lack of folic acid, iron, zinc, and vitamin B-12 in the diet
Being obese or overweight
Benign polyps or tumors (fibroids or myomas) in the uterus
Cancer
Cervical stenosis
Chemotherapy
Eating disorders
Exposure to some chemicals such as some pesticides, herbicides, metals
Hyperprolactinemia
Mental stress
Older age
Ovulation disorders
Pelvic surgery
Poor egg quality
Previous sterilization treatment
Problems in the uterus or fallopian tubes
Radiation therapy
Sexually transmitted infections (STIs) like Chlamydia
Submucosal fibroids
Too much and too little exercise
Use of Non-steroidal anti-inflammatory drugs or any illegal drugs
Uterine abnormalities present from birth
Gynecologist and Obstetrician