Lithium treatment for bipolar disorder should not be considered an absolute contraindication during pregnancy, as the risks from its use are relatively low, researchers say.

However, the international team recommends that pregnancy should be planned during remission and that lithium is prescribed within the lowest therapeutic range, particularly during the woman’s first trimester and immediately before delivery.

The group has conducted a systematic review and meta-analysis to ‘resolve uncertainties’ around balancing the need to prevent mood relapse in pregnancy with reducing the risk of adverse fetal outcomes.

“Our analyses indicated that lithium has a relatively favourable risk-benefit profile, with a [number needed to treat] of three, counterbalanced by a [number needed to harm] of 33,” they wrote.