Psoriasis is an immune-mediated inflammatory disease which has been found to influence the hormone levels of pregnant women, with up to 23% of patients experiencing exacerbation during pregnancy and 65% experiencing worsening conditions after delivery.¹ Additionally, psoriasis is associated with undesirable maternal outcomes, often resulting in elevated risk of preeclampsia, pregnancy-related hypertension, and severe post-partum hemorrhage.² Despite the availability of biologic therapies for psoriasis, it is a challenge when it comes to treating pregnant patients due to the limited understanding of their safety.³ Hence, a meta-analysis has been conducted to address the knowledge gap and investigated the effects of biologic therapies on pregnancy outcomes in women with psoriasis.³

The meta-analysis conducted a systematic literature review on English, Spanish and Italian academic papers published as of 14 April 2022, which included randomized controlled trials, cohort studies, case-control studies, case series, case report studies, and patient registries.³ The primary endpoints of this meta-analysis were the pregnancy outcomes of patients, including live births, miscarriages, elective abortions, unspecified abortions, and congenital malformations (i.e., structural or functional abnormalities present at birth in live births).³ The secondary endpoints focused on live birth outcomes, including the frequency of small for gestational age (SGA) (i.e., birthweight <10^th centile for gestation and sex), preterm birth (i.e., birth before 35 weeks of gestation), low birth weight (<2.5kg), neonatal complications [i.e., neonatal respiratory distress syndrome (RDS), neonatal interventricular hemorrhage (IVH), neonatal necrotizing enterocolitis (NEC), neonatal sepsis, admission to the neonatal intensive care unit (NICU)], information on child morbidity, and the long-term growth and development.³

The literature review yielded a total of 51 studies with 739 psoriasis patients who had been exposed to at least 3 months of biologics treatment before or during pregnancy, with plaque psoriasis being the dominant type of psoriasis among patients (96.7%).³ The mean duration of biologic exposure was 16.8 weeks, with ustekinumab (35.9%), etanercept (19.3%), and infliximab (12.7%) being the conventional biologics utilized for treating psoriasis.³ Biologic exposures were limited to the first trimester of pregnancy and suspended during pregnancy for 70.4% and 77.6% of patients, respectively.³

Overall, the pooled data estimated the prevalence of miscarriage of 15.3% (95% CI: 12.7-18.0), with low heterogeneity (I²=0%; 95% CI: 0-31.2), elective abortion of 10.8% (95% CI: 7.7-14.3; I²=23.7%; 95% CI: 0-46.9).³ The estimated prevalence for total abortions was 23.7% (95% CI: 18.8-29.0; I²=36.5%; 95% CI: 2.3-55.2).³ No associations between exposure to a specific biologic treatment and pregnancy outcomes were observed.³

As to the secondary endpoints, the reported outcomes varied among all articles in the analysis.³ Specifically, the incidence rate of SGA was reported in only 8 studies, resulting in an estimated incidence rate of 7.9%.³ The prevalence of preterm delivery was estimated to be 15%, concluding from 283 live birth outcomes of 36 studies.³ In terms of congenital malformations, 24 studies with a pooled population of 492 were included, resulting in an estimated prevalence of 3.0% (95% CI: 1.6-4.8; I²= 10.5%; 95% CI: 0-45.8).³

To sum up, the results of this meta-analysis exhibited a weak association between biologic exposure for psoriasis treatment during pregnancy and a higher risk of miscarriages or congenital malformations, regardless of the administered biologic therapies.³ These findings suggested that biologics were generally well tolerated, with manageable risk towards pregnancy and live birth outcomes.³ Nevertheless, further research is still required to address the clinical uncertainties of biologic usage in treating pregnant patients with psoriasis.³