NEW YORK (Reuters) -- A person's chances of having hearing loss in adulthood may be influenced by events that occur before birth, new research suggests.

According to the "thrifty phenotype hypothesis," events that occur when a person is just a fetus can cause disease later in life. The current findings suggest that this hypothesis holds true for hearing loss, Swedish researchers note in the British Medical Journal.

"During certain periods of the pregnancy, (cell growth is increased) in order to develop complicated organs - for example, the skeleton, the heart, and organs in the head -- over a short period of time," Dr. Marie-Louise Barrenas explained to Reuters Health.

However, malnourished fetuses or those exposed to toxins such as alcohol or nicotine make metabolic adaptations that persist throughout life, Barrenas and associates at Goteborg University propose. "According to our hypothesis, there are substances or genetic cell damages that affect (cell growth) so that it can not be maximally (increased) during the short time window available."

As a result of reduced cell growth, she added, some organs are smaller in size at birth and remain so throughout life. Lower levels of an insulin-like chemical, linked to ear development, short stature and heart disease, may be at least one of the culprits.

To test their hypothesis, they used audiometry to assess hearing in 479 men with occupational exposure to noise. Short men were three times more likely than taller men to have diminished hearing.

Barrenas' group also examined data for 500 men born in 1974. In this group, shortness was twice as common in those with hearing loss as in men with normal hearing.

Barrenas noted that interventions to increase the insulin-like chemical could perhaps prevent or reverse hearing loss, but there is some danger in such an approach, since the chemical causes changes that may lead to cancer.

Her group now plans to conduct animal studies to investigate "methods to increase growth-stimulating substances in the" inner ear.