Causes in women
Infertility in women can also have a range of causes.
Risk factors that increase the risk include:
- Age: The ability to conceive starts to fall around the age of 32 years.
- Smoking: Smoking significantly increases the risk of infertility in both men and women, and it may undermine the effects of fertility treatment. Smoking during pregnancy increases the chance of pregnancy loss. Passive smoking has also been linked to lower fertility.
- Alcohol: Any amount of alcohol consumption can affect the chances of conceiving.
- Being obese or overweight: This can increase the risk of infertility in women as well as men.
- Eating disorders: If an eating disorder leads to serious weight loss, fertility problems may arise.
- Diet: A lack of folic acid, iron, zinc, and vitamin B-12 can affect fertility. Women who are at risk, including those on a vegan diet, should ask the doctor about supplements.
- Exercise: Both too much and too little exercise can lead to fertility problems.
Sexually transmitted infections (STIs): Chlamydia can damage the fallopian tubes in a woman and cause inflammation in a man’s scrotum. Some other STIs may also cause infertility.
- Exposure to some chemicals: Some pesticides, herbicides, metals, such as lead, and solvents have been linked to fertility problems in both men and women. A mouse study has suggested that ingredients in some household detergents may reduce fertility.
- Mental stress: This may affect female ovulation and male sperm production and can lead to reduced sexual activity.
Some medical conditions can affect fertility.
Ovulation disorders appear to be the most common cause of infertility in women.
Ovulation is the monthly release of an egg. The eggs may never be released or they may only be released in some cycles.
Ovulation disorders can be due to:
- Premature ovarian failure: The ovaries stop working before the age of 40 years.
- Polycystic ovary syndrome (PCOS): The ovaries function abnormally and ovulation may not occur.
- Hyperprolactinemia: If prolactin levels are high, and the woman is not pregnant or breastfeeding, it may affect ovulation and fertility.
- Poor egg quality: Eggs that are damaged or develop genetic abnormalities cannot sustain a pregnancy. The older a woman is, the higher the risk.
- Thyroid problems: An overactive or underactive thyroid gland can lead to a hormonal imbalance.
- Chronic conditions: These include AIDS or cancer.
Problems in the uterus or fallopian tubes can prevent the egg from traveling from the ovary to the uterus, or womb.
If the egg does not travel, it can be harder to conceive naturally.
- Surgery: Pelvic surgery can sometimes cause scarring or damage to the fallopian tubes. Cervical surgery can sometimes cause scarring or shortening of the cervix. The cervix is the neck of the uterus.
- Submucosal fibroids: Benign or non-cancerous tumors occur in the muscular wall of the uterus. They can interfere with implantation or block the fallopian tube, preventing sperm from fertilizing the egg. Large submucosal uterine fibroids may make the uterus’ cavity bigger, increasing the distance the sperm has to travel.
- Endometriosis: Cells that normally occur within the lining of the uterus start growing elsewhere in the body.
- Previous sterilization treatment: In women who have chosen to have their fallopian tubes blocked, the process can be reversed, but the chances of becoming fertile again are not high.
Medications, treatments, and drugs
Some drugs can affect fertility in a woman.
- Non-steroidal anti-inflammatory drugs (NSAIDs): Long-term use of aspirin or ibuprofen may make it harder to conceive.
- Chemotherapy: Some chemotherapy drugs can result in ovarian failure. In some cases, this may be permanent.
- Radiation therapy: If this is aimed near the reproductive organs, it can increase the risk of fertility problems.
- Illegal drugs: Some women who use marijuana or cocaine may have fertility problems.