Women

General factors  that can affect  a woman’s ability  to ovulate, conceive or deliver a   child  successfully include the following :

• Age : Women in their late 30s and older are generally less fertile than women in their early 20s
• Endometriosis
• Hormonal imbalance
• Chronic diseases such as diabetes, high blood pressure, lupus or asthma
• Being overweight to underweight
• Environmental factors such as cigarette smoking, alcohol consumption  or exposure to workplace hazards and toxins.
• Abnormal pap smear that have been treated with cryosurgery or cone biopsy
• Sexually transmitted diseases
• DES  taken by mother during pregnancy
• Fallopian tube disease
• Multiple miscarriages

Men

List of factors related to male infertility include the following :

• Heavy alcohol consumption
• History of prostatitis, genital infection or sexually transmitted diseases
• Cigarette or marijuana smoking
• Hernia repair
• Exposure to hazards on the job or toxic substances  such as radiation, radioactivity , welding and many chemicals including ethylene dibromine and vinyl chloride .
• Undescended testicles
• Prescription drugs  for ulcers  or psoriasis
• DES taken by mother during pregnancy
• Mumps after puberty