[Syphilis and pregnancy]

Syphilis is a bacterial infection caused by the species Treponema pallidum subsp. pallidum, transmitted both sexually and vertically. The disease progresses in three distinct stages, with a high risk of contagion in the early stages. The infection has seen a resurgence in several countries around the world and is particularly concerning during pregnancy.Indeed, from the 16th week of gestation, the treponema can cross the placenta and infect the fetus and it can cause placental and/or fetal lesions. Maternal-fetal transmission is more common in the early stages of the disease. The consequences are variable, with polyvisceral involvement (spleen, liver, intestine) and other alterations. The pathological sequence can, in extreme cases, lead to fetal hydrops, premature birth, or even fetal death. Antenatal ultrasound provides evidence for fetal involvement but cannot definitively rule it out. The severity of the abnormalities does not depend on the term of the pregnancy, and there is no teratogenic risk.For pregnancies that result in a live birth, congenital syphilis is often exacerbated by prematurity and hypotrophy, which can lead to complications and sequelae. Following appropriate treatment, clinical, biological, and ultrasound monitoring during pregnancy is indicated. Clinical and biological assessment during the neonatal period is essential.A strategy based on early screening and treatment during pregnancy can help reduce the impact of this pathology on pregnancies worldwide.