Women who take antidepressants while pregnant are more likely to give birth prematurely, new research suggests.

"Preterm birth is a major clinical problem throughout the world and rates have been increasing over the past two decades. At the same time, rates of antidepressant use during pregnancy have also increased. Therefore it is essential to determine what effects these medications have on pregnancy," US scientists said.

They carried out a major review of 41 studies on this topic and found that all of the evidence suggests that ‘antidepressant use in pregnancy is associated with preterm birth'.

However, the scientists emphasised that the treatment of depression during pregnancy ‘is complex and there are many factors to consider'.

"Pregnant women and their providers need to weigh many issues. It is crucial, though, that the public gets accurate information on this topic," they insisted.

They pointed out that children born early have higher infant mortality rates than full-term babies. They also have an increased risk of suffering health problems, such as developmental problems, cerebral palsy and asthma.

"Preterm birth is the leading cause of infant death and it is also a major contributor to both short and long-term illness. While very preterm infants have the highest risk, we now know that even later preterm birth is associated with significant increases in neonatal morbidity and mortality," the scientists said.

Their study showed that the link between antidepressant use and premature births was strongest when the drugs were taken during the third trimester.

However, the scientists insisted that their results ‘should not be seen as an argument to ignore depression in these patients'.

"Pregnant women with depression need proper treatment. These drugs may be necessary in some pregnant women with severe depression in whom other approaches are inadequate. However, for many others, non-drug treatments, such as psychotherapy, will help, and aren't associated with complications like preterm birth," they added.

Details of these findings are published in the journal, PLOS ONE.

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