New York, Dec 22 (IANS): Exposure to metals such as nickel, arsenic, cobalt and lead may disrupt a woman's hormones during pregnancy which may lead to children's later health and disease risks, says a new study.

Exposure to metals has been associated with problems at birth such as pre-term birth and low birth weight in babies, and pre-eclampsia in women.

However, little is known about how metals exposure can lead to such problems.

This new research, published in the journal Environment International, shows that some metals may disrupt the endocrine system, which is responsible for regulating our body's hormones.

These disruptions may contribute to children's later health and disease risks.

"A delicate hormonal balance orchestrates pregnancy from conception to delivery and perturbations of this balance may negatively impact both mother and foetus," said lead author Zorimar Rivera-Nunez, Assistant Professor at the Rutgers University in the US.

The researchers analysed blood and urine samples from 815 women enrolled in the Puerto Rico Test site for Exploring Contamination Threats (PROTECT) study.

Initiated in 2010, PROTECT is an ongoing prospective birth cohort studying environmental exposures in pregnant women and their children around the northern karst zone, which includes urban and mountainous rural areas of Puerto Rico.

They found that metals can act as endocrine disruptors by altering prenatal hormone concentrations during pregnancy. This disruption may depend on when in the pregnancy the mother was exposed.

Among pregnant women, metal exposure is higher in those living in Puerto Rico than in those in the continental United States.

"This is important because, compared to the US overall, women in Puerto Rico have significantly higher rates of preterm birth (nearly 12 percent) and other adverse birth outcomes," Rivera-Nunez said.