Mpox Infection in Pregnancy Linked to High Risk of Fetal Loss: Lancet
A new study published in the journal of The Lancet showed that a substantial risk of fetal death is linked to monkey pox (mpox) infection during pregnancy, particularly in the first trimester.
Mpox often affects people of reproductive age since sexual contact is one of the primary ways that monkeypox virus (MPXV) is transmitted, which raises concerns about the consequences of infection on mothers and newborns during pregnancy. Thus, this study characterized the virological, clinical, and sociodemographic features of MPXV clade I infection in pregnant women as well as to evaluate the prevalence and risk factors of unfavorable outcomes.
Data from three cohort studies (PREGMPOX, MBOTE-SK, and Uvira mpox) and one randomized controlled trial (PALM007) carried out in the DR Congo's South Kivu, Maniema, and Sankuru provinces between December 29, 2022, and June 20, 2025, were combined for this prospective cohort research. Adolescent girls and pregnant women with a PCR-confirmed diagnosis of mpox were monitored during their hospital stay, birth, and postpartum discharge. This research gathered information on test findings, clinical and obstetric presentation, MPXV exposure, and sociodemographic traits.
The following adverse outcomes were examined in a univariable analysis: spontaneous or missed abortion (less than 20 weeks of gestation), stillbirth (more than 20 weeks of gestation), preterm birth (less than 37 weeks of gestation), early (first 7 days) neonatal death, live birth of a neonate with macroscopic mpox-like lesions,
4 trials with 89 pregnant women who had mpox were combined, and the subjects were spread over all trimesters. There were no maternal fatalities, and every woman recovered. In 19% of cases, fetal loss occurred while the patient was in the hospital.
Of the 69 women whose pregnancy outcomes were known, 51% had unfavorable outcomes, including fetal loss in 45% of cases (spontaneous abortions, missed abortions, and stillbirths). There were no preterm births or congenital abnormalities among the 38 live births; 4 neonates developed congenital mpox-like lesions and one neonatal death.
When compared to subsequent trimesters, a first-trimester Mpox infection associated a much increased risk of unfavorable consequences. High viral load, sexual exposure, HIV positive, and genital lesions were additional risk factors. Overall, MPXV clade Pregnancy-related infections, especially in the first trimester, are linked to an increased risk of congenital infection and fetal death.
Source:
Vakaniaki, E. H., Barhishindi, I., Mubiala, A., Malembaka, E. B., Braunack-Mayer, L., Nganga, B., Sabiti Nundu, S., Brosius, I., Bracke, S., Bangwen, E., De Vos, E., Colebunders, R., Ngale, M., Kayembe, G., Tshongo, C., Dilu, A., Tshimanga, C., Biampata, J.-L., Bugeme, P. M., … Liesenborghs, L. (2025). Maternal and neonatal outcomes after infection with monkeypox virus clade I during pregnancy in DR Congo: a pooled, prospective cohort study. Lancet. https://doi.org/10.1016/s0140-6736(25)02309-8
