Andrea Gehrmann, Katrin Fiedler, Anna Linda Leutritz, Carolin Koreny, Sarah Kittel-Schneider

• Lithium salts are the first-line prophylaxis treatment for bipolar disorder in most guidelines. The majority of bipolar women are treated with mood stabilizers at the time they wish to get pregnant. One reason for this is the rising average age at first childbirth, at least in the high-income countries, which increases in general the likelihood of a medication with psychotropic drugs. Previously, lithium exposition during pregnancy was thought to strongly increase the risk of severe cardiac malformation. However, recent studies only point to aLithium salts are the first-line prophylaxis treatment for bipolar disorder in most guidelines. The majority of bipolar women are treated with mood stabilizers at the time they wish to get pregnant. One reason for this is the rising average age at first childbirth, at least in the high-income countries, which increases in general the likelihood of a medication with psychotropic drugs. Previously, lithium exposition during pregnancy was thought to strongly increase the risk of severe cardiac malformation. However, recent studies only point to a low teratogenic risk, so nowadays an increasing number of women are getting pregnant with ongoing lithium treatment. Regarding lithium medication during breastfeeding, there is evidence that lithium transfers to the breastmilk and can also be detected in the infants' serum. The influence on the infant is still a largely understudied topic. Regular monitoring of the infants' renal clearance, thyroid function, and lithium levels is warranted when breastfeeding under lithium exposure. In this case series, we present three case reports of bipolar mothers who were treated with lithium during pregnancy and breastfeeding to add to the scarce literature on this important topic. In short, we strengthen the importance of therapeutic drug monitoring due to fluctuating plasma levels during pregnancy and after birth, and we can report the birth and development of three healthy infants despite lithium medication during pregnancy and breastfeeding.…