Lithium exposure during pregnancy increases fetal growth

Area of Science:

• Perinatal medicine
• Obstetrics
• Psychiatry

Background:

• Lithium is a vital treatment for bipolar disorder during pregnancy and postpartum.
• Knowledge regarding lithium's impact on fetal development is limited.
• This study addresses the need for data on lithium's effects on early fetal growth.

Purpose of the Study:

• To investigate the impact of maternal lithium exposure on early fetal growth parameters.
• To assess changes in fetal measurements during the second trimester of pregnancy.

Main Methods:

• Retrospective observational cohort study comparing pregnancies with lithium use (n=119) to a control group (n=8184).
• Advanced fetal ultrasound scans were used to measure fetal head circumference, abdominal circumference, femur length, and transcerebellar diameter between 18-22 weeks of gestation.
• Data collected between 1994 and 2018 from Dutch medical centers.

Main Results:

• Lithium exposure was associated with increased fetal head circumference (1.77 mm), abdominal circumference (5.54 mm), and femur length (0.59 mm) at 18-22 weeks gestation.
• A significant increase in birth weight (142.43 grams) was observed in infants exposed to lithium.
• Lithium use was also associated with a shorter gestational duration (1.41 weeks).

Conclusions:

• Maternal lithium use during pregnancy correlates with enhanced fetal growth parameters and higher birth weight.
• The findings highlight a need for further investigation into the short- and long-term implications of these growth differences.
• Understanding the mechanisms behind lithium's effect on fetal growth is crucial.