Lithium is an effective treatment in pregnancy and postpartum for the prevention of relapse in bipolar disorder. However, lithium has also been associated with risks during pregnancy for both the mother and the unborn child. Recent large studies have confirmed the association between first trimester lithium exposure and an increased risk of congenital malformations. Importantly, the risk estimates from these studies are lower than previously reported. Tapering of lithium during the first trimester could be considered but should be weighed against the risks of relapse. There seems to be no association between lithium use and pregnancy or delivery related outcomes, but more research is needed to be more conclusive. When lithium is prescribed during pregnancy, lithium blood levels should be monitored more frequently than outside of pregnancy and preferably weekly in the third trimester. We recommend a high-resolution ultrasound with fetal anomaly scanning at 20 weeks. Ideally, delivery should take place in a specialised hospital where psychiatric and obstetric care for the mother is provided and neonatal evaluation and monitoring of the child can take place immediately after birth. When lithium is discontinued during pregnancy, lithium could be restarted immediately after delivery as strategy for relapse prevention postpartum. Given the very high risk of relapse in the postpartum period, a high target therapeutic lithium level is recommended. Most clinical guidelines discourage breastfeeding in women treated with lithium. It is highly important that clinicians inform and advise women about the risks and benefits of remaining on lithium in pregnancy, if possible preconceptionally. In this narrative review we provide an up-to-date overview of the literature on lithium use during pregnancy and after delivery leading to clinical recommendations.

Lithium and antipsychotics are often prescribed to treat bipolar disorder or psychotic disorders in women of childbearing age. Little is known about the consequences of these medications during pregnancy for the developing child. The objective of this article is to systematically review findings from preclinical and clinical studies that have examined the neurodevelopmental consequences of intrauterine exposure to lithium and antipsychotics. A systematic search was performed in Embase, Medline, Web of Science, PsychINFO, Cochrane, and Google Scholar. Clinical and experimental studies were selected if they investigated neurodevelopment of offspring exposed to lithium or antipsychotics during gestation. Quality of clinical and preclinical studies was assessed by the Newcastle–Ottawa Scale and the SYRCLE’s risk of Bias tool, respectively. In total, 73 studies were selected for qualitative synthesis and three studies were selected for quantitative synthesis. Of preclinical studies, 93% found one or more adverse effects of prenatal exposure to antipsychotics or lithium on neurodevelopment or behaviour. Only three clinical cohort studies have investigated the consequences of lithium exposure, all of which reported normal development. In 66% of clinical studies regarding antipsychotic exposure, a transient delay in neurodevelopment was observed. The relative risk for neuromotor deficits after in utero exposure to antipsychotics was estimated to be 1.63 (95% CI 1.22–2.19; I² = 0%). Preclinical studies suggest long-term adverse neurodevelopmental consequences of intrauterine exposure to either lithium or antipsychotics. However, there is a lack of high-quality clinical studies. Interpretation is difficult, since most studies have compared exposed children with their peers from the unaffected population, which did not allow correction for potential influences regarding genetic predisposition or parental psychiatric illness.

Recent studies have provided new data on the teratogenicity of lithium. Less is known about the risk of miscarriage after lithium use during pregnancy. The aim of this study was to investigate the association between lithium use during pregnancy and miscarriage. Participants were women with bipolar I disorder and one or more pregnancies, of which information on medication use and pregnancy outcome was available (n = 443). The unadjusted odds ratios for miscarriage after lithium use during pregnancy was calculated. Multilevel logistic regression was used to calculate the odds ratio, adjusted for the age at conception and the clustering of pregnancies per woman. Miscarriages occurred in 20.8% of the lithium-exposed pregnancies (16/77), compared with 10.9% of the unexposed pregnancies (40/366) (OR = 2.14; 95% CI: 1.13–4.06). The adjusted odds ratio of miscarriage after lithium use during pregnancy was 2.94 (95% CI: 1.39–6.22). Lithium use during pregnancy may increase the risk of miscarriage.

Objectives: Lithium is an effective treatment for bipolar disorder, also during pregnancy to prevent the recurrence of episodes in the perinatal period. Little is known about the neuropsychological development of lithium‐exposed offspring. The current study was designed to investigate neuropsychological functioning in lithium‐exposed children with the aim to provide further knowledge on the long‐term effects of lithium use during pregnancy.Methods: Participants were offspring of women with a diagnosis of bipolar spectrum disorder, aged 6–14 years. In total, 99 children participated in the study, 56 were exposed to lithiumin uteroand 43 were not exposed to lithium. Neuropsychological tests were administered, including the Snijders‐Oomen Nonverbal Intelligence Test and the NEPSY‐II‐NL assessment. Linear and negative binomial regression models were used to investigate the association between prenatal lithium exposure and neuropsychological functioning. In secondary analyses, the association between lithium blood level during pregnancy and neuropsychological functioning was assessed. Additionally, norm scores and percentiles for task outcomes were calculated.Results: Lithium use during pregnancy was associated with the total number of mistakes made on the Auditory Attention task, but not statistically significant after full adjustment for potential confounding factors. No association between prenatal lithium exposure and IQ was found. Also, no relationship between lithium blood level during pregnancy and neuropsychological functioning was found after adjustment for potential confounders. Task outcomes in both groups were comparable to the general population.Conclusion: In this study, we found no evidence for significantly altered neuropsychological functioning of lithium‐exposed children at the age of 6–14 years, when compared to non‐lithium‐exposed controls.

Lithium is an effective treatment in pregnancy and postpartum for the prevention of relapse in bipolar disorder, but there is a lack of knowledge about the potential adverse impact on fetal development. To investigate the impact of lithium exposure on early fetal growth. In this retrospective observational cohort study, we included all singleton pregnancies of women using lithium and referred for advanced fetal ultrasound scanning between 1994 and 2018 to the University Medical Centers in Leiden and Rotterdam, the Netherlands (n=119). The Generation R study, a population-based cohort, served as a non-exposed control population from the same geographic region (n=8184). Fetal head circumference, abdominal circumference, femur length, and transcerebellar diameter were measured by ultrasound at 18–22 weeks of gestation. Lithium use during pregnancy was associated with an average increase in head circumference of 1.77 mm (95% confidence interval: 0.53, 3.01), in abdominal circumference of 5.54 mm (95% confidence interval: 3.95, 7.12) and in femur length of 0.59 mm (95% confidence interval: 0.22, 0.96) at 18–22 weeks gestation. Furthermore, lithium use during pregnancy was associated with an average increase in birth weight of 142.43 grams (95% confidence interval: 58.01, 226.89), whereas it was associated with an average decrease of 1.41 weeks in gestational duration (95% confidence interval: −1.78, −1.05). Lithium use during pregnancy was associated with increased fetal growth parameters at 18–22 weeks gestational age and increased birth weight. Further research is needed to evaluate both short- and long-term implications, as well as the mechanisms driving this difference in growth.

Increasing evidence suggests that the physiological changes of pregnancy may impact pharmacokinetics of antiseizure medications (ASM), and this may affect treatment outcomes. The aim of this study was to quantify the pregnancy impact on the ASM pharmacokinetics. A systematic literature search was conducted in PubMed/EMBASE in November 2022 and updated in August 2023 for studies comparing levels of ASM in the same individuals during pregnancy and in the preconception/postpartum period. Alteration ratios between the 3rd trimester and baseline were estimated. We also performed a random-effects meta-analysis calculating between-timepoint differences in mean differences (MDs) and 95% confidence intervals (95%CIs) for dose-adjusted plasma concentrations (C/D ratios). Study quality was assessed using the ClinPK guidelines. A total of 65 studies investigating 15 ASMs in 674 pregnancies were included. The largest differences were reported for lamotrigine, oxcarbazepine and levetiracetam (alteration ratio 0.42, range 0.07-2.45, 0.42, range 0.08-0.82 and 0.52, range 0.04-2.77 respectively): accordingly, C/D levels were lower in the 3rd trimester for lamotrigine, levetiracetam and the main oxcarbazepine metabolite monohydroxycarbazepine (MD = -12.33 × 10^-3, 95%CI = -16.08 to -8.58 × 10^-3 (μg/mL)/(mg/day), p < 0.001, MD = -7.16 (μg/mL)/(mg/day), 95%CI = -9.96 to -4.36, p < 0.001, and MD = -4.87 (μg/mL)/(mg/day), 95%CI = -9.39 to -0.35, p = 0.035, respectively), but not for oxcarbazepine (MD = 1.16 × 10^-3 (μg/mL)/(mg/day), 95%CI = -2.55 to 0.24 × 10^-3, p = 0.10). The quality of studies was acceptable with an average rating score of 11.5. Data for lamotrigine, oxcarbazepine (and monohydroxycarbazepine) and levetiracetam demonstrate major changes in pharmacokinetics during pregnancy, suggesting the importance of therapeutic drug monitoring to assist clinicians in optimizing treatment outcomes.