Pregnancy outcomes after snakebite envenomations: A retrospective cohort in the Brazilian Amazonia

Snakebite envenomations (SBEs) in pregnant women can result in adverse maternal or neonatal effects, such as abortion, placental abruption, preterm labor, fetal malformations, and maternal, fetal or neonatal deaths. Despite the high incidence of SBEs in the Brazilian Amazon, there is no literature on the impact of SBEs on pregnancy outcomes. The objective of this study was to describe clinical epidemiology and outcomes associated with SBEs in women of childbearing age and pregnant women in the state of Amazonas, Western Brazilian Amazon, from 2007 to 2021. Information on the population was obtained from the Reporting Information System (SINAN), Mortality Information System (SIM) and Live Birth Information System (SINASC) for the period from 2007 to 2021. A total of 36,786 SBEs were reported, of which 3,297 (9%) involved women of childbearing age, and 274 (8.3%) involved pregnant women. Severity (7.9% in pregnant versus 8.7% in non-pregnant women) (P = 0.87) and case-fatality (0.4% in pregnant versus 0.3% in non-pregnant women) rates were similar between groups (P = 0.76). Pregnant women who suffered snakebites were at higher risk for fetal death (OR: 2.17, 95%CI: 1.74-2.67) and neonatal death (OR = 2.79, 95%CI: 2.26-3.40). This study had major limitations related to the completeness of the information on the pregnancy outcomes. Although SBE incidence in pregnant women is low in the Brazilian Amazon, SBEs increased the risk of fetal and neonatal deaths. Author summary Snakebite envenomations (SBEs) are a health problem in tropical and subtropical countries. In endemic areas, this health problem more frequently involves men engaged in agricultural activities. However, in many areas of the world, women of childbearing age are also very affected by snakebites, as they also actively participate in activities that put them at risk of encountering snakes. In this context, SBEs can occur during pregnancy, with deleterious consequences for both the mother and the fetus or neonate. However, the little that is known about the consequences of SBEs in pregnancy comes from case reports. In this study, we linked the surveillance databases Snakebites Reporting Information System (SINAN), Mortality Information System (SIM) and Live Birth Information System (SINASC) of the state of Amazonas, Western Brazilian Amazon, to gain a more integrative view of the problem in the region. Although severity and case-fatality rates of SBEs were similar between pregnant and non-pregnant women, pregnant women who suffered SBEs were at higher risk for fetal and neonatal deaths.

Automated summary

Snakebite envenomations during pregnancy in the Brazilian Amazon increase the risk of fetal and neonatal deaths, despite the low incidence of snakebites in pregnant women.