Lithium exposure during pregnancy increases fetal growth

Dose response relationship between lithium serum levels during pregnancy and birth outcomes

INTRODUCTION

Lithium use during pregnancy reduces the risk of mood episodes in the perinatal period for women with bipolar disorder. Some previous studies found deleterious effects of intrauterine lithium exposure on birth outcomes, yet little is known about a dose response relationship. The current study investigated the influence of maternal lithium serum levels on birth outcomes.

METHODS

This retrospective observational cohort study included women with a bipolar spectrum disorder who were referred to a specialized psychiatric and obstetric outpatient clinic from 2003 to 2019 and used lithium during the entire pregnancy. For 101 pregnancies at least one lithium level during pregnancy was available. A weighted average lithium level was calculated for the entire pregnancy, as well as for each trimester. Detailed information on maternal, obstetric and neonatal outcomes were retrieved from the medical records. Linear and logistic regression models were used to investigate the association between weighted average lithium level and pregnancy duration, birth weight percentiles, preterm birth and large for gestational age births (LGA). In subsequent exploratory analyses, we studied the role of thyroid-stimulating hormone (TSH) and thyroxine (T4) as a mediator in the found associations.

RESULTS

The weighted average lithium serum level during pregnancy was negatively associated with pregnancy duration and positively with preterm birth, but not with birth weight percentile or LGA. In exploratory analyses, TSH and T4 did not mediate the association between average lithium serum level and pregnancy duration.

CONCLUSION

The results of this cohort study during pregnancy indicate a dose response relationship between maternal lithium serum levels and pregnancy duration.

Striking the Balance: Bipolar Disorder in the Perinatal Period

The authors reviewed the literature, published between 2018 and 2023, on treating bipolar disorder in the perinatal period in order to summarize current treatment perspectives. Mood episodes occur during pregnancy and there are high rates of both initial onset and recurrence in the postpartum period. Bipolar disorder itself is associated with higher risks of adverse pregnancy outcomes, including gestational hypertension, hemorrhage, cesarean delivery, and small for gestational age infants. A general principle of perinatal treatment includes maintaining psychiatric stability of the pregnant person while reducing medication exposure risk to the fetus. A variety of factors can compromise psychiatric stability, including rapid discontinuation of stabilizing medications, decreased efficacy due to physiologic changes of pregnancy, and exacerbation of underlying psychiatric illness. Psychosocial interventions include optimizing sleep, increasing support, and reducing stress. The American College of Obstetricians and Gynecologists recommends against discontinuing or withholding medications solely due to pregnancy or lactation status. Individualized treatment involves a discussion of the risks of undertreated bipolar disorder weighed against the risks of individual medication choice based on available evidence regarding congenital malformations, adverse neonatal and obstetrical events, and neurodevelopmental outcomes. Valproate is not a first-line treatment due to higher risks. Data are lacking on safety for many newer medications. The authors review current safety data regarding lithium, lamotrigine, and antipsychotics, which are the most commonly used treatments for managing bipolar disorder in the perinatal period. Due to physiologic changes during pregnancy, frequent therapeutic drug monitoring and dose adjustments are required.

Neonatal admission after lithium use in pregnant women with bipolar disorders: a retrospective cohort study

BACKGROUND

Lithium is the preferred treatment for pregnant women with bipolar disorders (BD), as it is most effective in preventing postpartum relapse. Although it has been prescribed during pregnancy for decades, the safety for neonates and obstetric outcomes are a topic of ongoing scientific debate as previous research has yielded contradicting outcomes. Our study aims to compare (re)admission rates and reasons for admissions in neonates born to women with bipolar disorders (BD) with and without lithium exposure.

METHODS

A retrospective observational cohort study was conducted in a Dutch secondary hospital (two locations in Amsterdam). Women with BD who gave birth after a singleton pregnancy between January 2011 and March 2021 and their neonates were included. Outcomes were obtained by medical chart review of mothers and neonates and compared between neonates with and without lithium exposure. The primary outcome was admission to a neonatal ward with monitoring, preterm birth, small for gestational age (SGA), 5-minute Apgar scores, neonatal asphyxia, and readmission ≤ 28 days.

RESULTS

We included 93 women with BD, who gave birth to 117 live-born neonates: 42 (36%) exposed and 75 (64%) non-exposed to lithium. There were no significant differences in neonatal admission with monitoring (16.7 vs. 20.0%, p = 0.844). Additionally, preterm birth (7.1 vs. 5.3%), SGA (0.0 vs. 8.0%), 5-minute Apgar scores (means 9.50 vs. 9.51), neonatal asphyxia (4.8 vs. 2.7%) and readmission (4.8 vs. 5.3%) were comparable. Overall, 18.8% of BD offspring was admitted. Women with BD had high rates of caesarean section (29.1%), gestational diabetes (12.8%) and hypertensive disorders of pregnancy (8.5%).

CONCLUSIONS

In a sample of neonates all born to women with BD using various other psychotropic drugs, exposure to lithium was not associated with greater risk of neonatal admission to a ward with monitoring compared to non-exposure to lithium, questioning the necessity for special measures after lithium exposure. However, offspring of women with BD was admitted regularly and women with BD have high obstetric risk which require clinical and scientific attention.

Updated perspectives on how and when lithium should be used in the treatment of mood disorders

INTRODUCTION

Lithium is one of the most important drugs for the treatment of mood disorders. The appropriate guidelines can ensure that more patients benefit from its use in a personalized way.

AREAS COVERED

This manuscript provides an update on the application of lithium in mood disorders, including prophylaxis of bipolar and unipolar mood disorder, treatment of acute manic and depressive episodes, augmentation of antidepressants in treatment-resistant depression, and use of lithium in pregnancy and the postpartum period.

EXPERT OPINION

Lithium remains the gold standard for the prevention of recurrences in bipolar mood disorder. For long-term treatment/management of bipolar mood disorder, clinicians should also consider lithium's anti-suicidal effect. Furthermore, after prophylactic treatment, lithium may also be augmented with antidepressants in treatment-resistant depression. There have also been some demonstration of lithium having some efficacy in acute episodes of mania and bipolar depression as well as in the prophylaxis of unipolar depression.

Brain development after intrauterine exposure to lithium: A magnetic resonance imaging study in school-age children

OBJECTIVE

Lithium is often continued during pregnancy to reduce the risk of perinatal mood episodes for women with bipolar disorder. However, little is known about the effect of intrauterine lithium exposure on brain development. The aim of this study was to investigate brain structure in children after intrauterine exposure to lithium.

METHODS

Participants were offspring, aged 8-14 years, of women with a diagnosis of bipolar spectrum disorder. In total, 63 children participated in the study: 30 with and 33 without intrauterine exposure to lithium. Global brain volume outcomes and white matter integrity were assessed using structural MRI and diffusion tensor imaging, respectively. Primary outcomes were total brain, cortical and subcortical gray matter, cortical white matter, lateral ventricles, cerebellum, hippocampus and amygdala volumes, cortical thickness, cortical surface area and global fractional anisotropy, and mean diffusivity. To assess how our data compared to the general population, global brain volumes were compared to data from the Generation R study (N = 3243).

RESULTS

In our primary analyses, we found no statistically significant associations between intrauterine exposure to lithium and structural brain measures. There was a non-significant trend toward reduced subcortical gray matter volume. Compared to the general population, lithium-exposed children showed reduced subcortical gray and cortical white matter volumes.

CONCLUSION

We found no differences in brain structure between lithium-exposed and non-lithium-exposed children aged 8-14 years following correction for multiple testing. While a rare population to study, future and likely multi-site studies with larger datasets are required to validate and extend these initial findings.

Neurodevelopment in school-aged children after intrauterine exposure to antipsychotics

OBJECTIVE

Antipsychotics are increasingly prescribed in pregnancy, yet little is known about potential long-term developmental effects on children. In this study, we investigated the effect of prenatal antipsychotic exposure on neurodevelopmental functioning in school-aged children.

METHODS

We performed a cross-sectional neurodevelopmental assessment of 91 children aged 6-14 years whose mothers had severe mental illness and were either exposed or unexposed to antipsychotic medication during pregnancy. Neurodevelopmental outcomes were assessed using validated neurodevelopmental assessment instruments to examine the child's IQ and global cognitive functioning, and the presence of any psychiatric disorders and/or learning problems in the child was assessed by parental report.

RESULTS

No statistically significant associations were found between antipsychotic exposure during pregnancy and either adverse neurodevelopmental outcomes (IQ, neuropsychological function), likelihood of psychiatric diagnosis, or learning problems based on parental report. Analyses were likely limited in power to detect subtler differences in neurodevelopmental functioning because of small sample size and heterogeneity of the sample.

CONCLUSIONS

In this exploratory cohort study, intrauterine exposure to antipsychotics was not associated with any adverse effect on IQ or neurodevelopmental functioning in a cohort of school-aged children (6-14 years).

Obstetric outcomes regarding the use of lithium in pregnant women with bipolar disorders: a prospective cohort study

Lithium is the mood stabilizer of choice for the prevention of bipolar relapse over the perinatal period. A critical issue is its safety of the mother and the developing fetus. This study aims to compare obstetric outcomes in women with bipolar disorders (BD) regarding treatment with lithium during pregnancy. We enrolled a cohort of pregnant women with BD that received care at the Perinatal Mental Health Unit of a tertiary hospital between January 2005 and March 2017. The exposed group received lithium during pregnancy, whereas the unexposed group did not. The main outcomes were obstetric complications during pregnancy, during labor and delivery, neonatal complications, and congenital malformations. Demographic and clinical data were described using measures of frequency, central tendency, and dispersion. Between-group differences were calculated with chi-square, Fisher's test, t-tests, or Mann-Whitney U test. Our cohort included 100 pregnant women with BD: 53 (53%) used lithium during pregnancy, and 47 (47%) did not. There were no significant differences in obstetric complications, neonatal complications, or congenital anomalies. Nonetheless, newborns of lithium-treated women had lower Apgar scores at 1 min (mean 8.2 ± 1.6 vs. 8.9 ± 0.6, p = 0.026) and 5 min (9.6 ± 0.8 vs. 9.9 ± 0.5, p = 0.015). Our findings do not identify worse obstetric outcomes in women with BD that take lithium during pregnancy, except for an impact on newborn Apgar scores. Lithium might be an adequate treatment for pregnant women with BD, especially for those with a high recurrence risk, and always after an individualized risk-benefit assessment.

The effect of prenatal lithium exposure on the neuropsychological development of the child

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 lithium in utero and 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.