A thin uterus lining is usually caused by an inadequate blood supply, low estrogen levels or damage to the uterus. The natural aging process can also cause a gradual thinning of the uterus lining. Adenomyosis is a condition that might lead to a thinner than normal uterus lining. It causes the lining to grow and develop within the uterus's muscles and is more common in older females.
An inadequate blood supply is a common cause of a thin uterus lining. For some reason, the blood flow to the uterus becomes abnormally low. Uterine blood flow is somewhat difficult to determine, but some doctors have tried a few prescription medications to correct the problem. These medications are designed to stimulate blood flow to reproductive organs and have shown some success.
Low estrogen levels are another common cause of a thinner uterus lining. Normal estrogen levels can be disrupted by hormonal changes, prescription medications and diseases, such as polycystic ovary syndrome (PCOS). Some hormonal changes are the result of the normal aging process. These can occur during puberty when the menstrual cycle is first beginning and in mid-life when the cycle is starting to terminate.
Women in their mid to late 40s might naturally develop a thin uterus lining. This is due to declining estrogen levels as the body enters into peri-menopause or menopause itself. Some women in their mid to late 30s also notice a natural decline in the lining's thickness.
Sometimes abnormal estrogen levels are due to underlying conditions. PCOS can lead to an imbalance between male and female reproductive hormones. The condition results in increased levels of androgens, which leads to irregular menstrual cycles, unwanted facial hair, male pattern baldness, cystic acne and pelvic pain. Once diagnosed, PCOS is a treatable condition with the use of birth control pills and other hormone regulators.
Damage to the uterus can cause the lining to become thinner than average. Scarring, inflammation and infection might cause the blood flow to become inadequate. Medical procedures have been developed to remove scarred tissue from the uterus to improve the thickness of its lining.
A condition known as adenomyosis causes the lining to accumulate within the uterus's muscles. This results in the interior lining becoming less dense or noticeable. Adenomyosis does not have a known cause, but is typically seen in women who are older. These women usually only have a few years of childbearing ability left.
There are some prescription medications that can lead to a thin uterus lining. Any medication that reduces estrogen levels can cause it. Long term use of these medications is usually associated with a thin uterus lining.