Bipolar disorder (BD) is a chronic mental health condition characterized by significant shifts in mood, energy, and activity levels. For individuals with BD who are pregnant or planning a family, maintaining effective treatment is a major consideration. Abruptly stopping medication is generally not recommended, as it increases the risk of a severe mood episode relapse. Relapse poses significant risks to both the mother and the developing fetus, including preterm birth and poor neonatal outcomes. The safest approach involves a careful, individualized treatment plan developed through close collaboration between the patient, their psychiatrist, and their obstetrician-gynecologist.
The Critical Role of Preconception Planning
Decisions about continuing or changing psychiatric medication should ideally begin before conception through preconception counseling. This planned approach allows the medical team to transition to the safest effective regimen before the critical period of fetal organ development. Decision-making relies on a careful risk-benefit analysis. This analysis balances the known, albeit small, risk of fetal exposure to a medication against the significant risk of an untreated or relapsing mood disorder. Untreated BD can lead to malnutrition, poor prenatal care, increased substance use, and an elevated risk of suicide, all of which substantially threaten the pregnancy. Consulting with a reproductive psychiatrist or a maternal-fetal medicine specialist provides access to the most current safety data, aiming for the lowest effective dose to maintain maternal stability.
Preferred Mood Stabilizers and Antipsychotics
Some medications used to treat BD have demonstrated a favorable safety profile during pregnancy and are often considered first-line options. Lamotrigine, a mood stabilizer, is generally preferred due to its relatively low teratogenic risk when used as monotherapy. Studies suggest that the risk of major congenital malformations with Lamotrigine monotherapy is around 2.0 to 2.7%, which is close to the risk observed in the general population. While earlier data suggested a specific risk of oral cleft defects, recent, larger studies have not found a clear, statistically significant association with Lamotrigine monotherapy. The risk of malformation increases if Lamotrigine is taken alongside other antiepileptic medications.
Atypical antipsychotics are also frequently chosen because they do not carry the high teratogenic risks of older mood stabilizers. Quetiapine and Lurasidone are two examples considered to have a relatively safe profile for use during pregnancy. Lurasidone has shown a favorable safety profile with better neonatal outcomes compared to untreated BD. Olanzapine is another option, though providers monitor for metabolic complications, such as gestational diabetes.
Medications Requiring Extreme Caution or Avoidance
Some effective mood stabilizers carry a significant risk of congenital malformations, necessitating extreme caution or avoidance. Valproate (valproic acid) is strongly advised against during pregnancy, particularly the first trimester, due to its high teratogenic risk. Exposure to Valproate is associated with a 3-5% risk of neural tube defects, such as spina bifida, and a higher risk of other malformations. Furthermore, Valproate exposure in the womb is linked to an increased risk of developmental and intellectual impairment in the child, which is a major concern.
Carbamazepine, another mood-stabilizing anticonvulsant, also poses a risk of neural tube defects, estimated at about 1%, which is lower than Valproate. Due to these specific risks, high-dose folic acid supplementation is especially critical for women who must remain on these medications. Lithium, while an extremely effective mood stabilizer, is associated with a small but measurable increase in the risk of cardiac malformations, specifically a rare defect called Ebstein’s anomaly. Current data suggests the absolute risk of this specific cardiac defect is low, approximately 0.1% or one additional case per 100 live births. Lithium remains a viable treatment option for individuals with severe or recurrent bipolar episodes when lower-risk options have failed to maintain stability.
Fetal Monitoring and Postpartum Management
Once a medication regimen is selected, specialized monitoring is required to track fetal health. For those exposed to Lithium during the first trimester, a fetal echocardiogram is recommended around 18 to 20 weeks to examine the heart structure. Detailed ultrasound scans are also performed to look for structural anomalies, especially neural tube defects if high-risk anticonvulsants are continued.
Physiological changes during pregnancy, like increased maternal blood volume, can cause drug levels to drop, potentially leading to relapse. For medications like Lithium, frequent therapeutic drug monitoring is necessary, sometimes as often as every three weeks, to ensure the dose remains in the optimal range. The postpartum period carries an extremely high risk of relapse or postpartum psychosis. A written relapse prevention plan should be established before delivery, outlining the immediate medication strategy. Doses are often increased quickly after birth to counteract hormonal and fluid shifts. Many preferred medications, such as Lamotrigine, Quetiapine, and Olanzapine, are compatible with breastfeeding, but the infant should be monitored for side effects.