Twin-to-twin transfusion syndrome (TTTS) is a serious complication of monochorionic twin pregnancies in which an imbalance in blood flow between the twins is caused by vascular anastomoses in the placenta. TTTS affects 10 to 15% of these monochorionic pregnancies and can lead to high perinatal mortality if left untreated. The Quintero classification, introduced in 1999, helps stratify the severity of TTTS into five stages, thereby facilitating clinical decision-making. Laser photocoagulation of placental anastomoses, a technique developped in the 2000s, has become the standard of care for severe stages, with significantly improved survival rates. Although this procedure is minimally invasive for the mother, it is not without risks to the pregnancy. Other strategies include amniodrainage to relieve maternal symptoms, expectant management in early stages, and sometimes selective termination of pregnancy. Twins often require intensive neonatal care and multidisciplinary follow-up to manage long-term complications. This complex syndrome requires management in specialized centers with expertise in fetal medicine.

Dysraphisms are characterized by an anomalie of the vertebrae and spinal cord. Only the prevalence of open dysraphisms is known, which in France is around 5 per 10,000 pregnancies. The prenatal diagnosis rate for open dysraphisms exceeds 95% in France, with a high rate of termination of pregnancy, close to 90%. Open dysraphisms (myelomeningocele and myeloschisis) represent the most severe forms and are associated with lower limb paralysis (the severity of which depends on the level of the defect), urinary sphincter incontinence (neurogenic bladder), and fecal incontinence, making a request for pregnancy termination admissible. However, the possibility of performing fetal repair surgery, which has been available in France since 2014, must now be included in prenatal prognostic information. While this surgery does not eliminate disabilities, its goal is to "protect" the fetal brain by stopping the leakage of cerebrospinal fluid, thus helping to correct/limit type II Chiari malformation. This, in turn, helps reduce secondary ventriculomegaly, decreases the need for postnatal ventriculoperitoneal shunting, and ultimately improves motor function.

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.

Following an initial phase characterized by a good response to dopaminergic therapies, Parkinson's disease progresses toward a stage marked by motor complications-notably motor fluctuations and dyskinesias. When the optimization of oral therapy proves insufficient, the use of second-line treatments must be considered. These strategies are based on three main approaches: deep brain stimulation, continuous subcutaneous infusions (apomorphine, foslevodopa-foscarbidopa), and intra-intestinal levodopa infusions. The indication for these therapies depends on a multidisciplinary assessment that considers dopa-responsiveness, motor and cognitive status, comorbidities, and the patient's lifestyle. At least 5 doses of L-dopa, 2 hours of OFF and 1 hour of disabling dyskinesias every day constitute a simple tool to identify eligible patients in routine practice. Therapeutic choices must be individualized, balancing efficacy, tolerability, and practical constraints. General practitioners play an essential role in identifying complications, monitoring treatment, and coordinating care. Early collaborative management can significantly improve patients' quality of life.

The growing number of French people over the age of 80 is putting a strain on the healthcare system. Ageism, rooted in age-related stereotypes and discrimination, negatively impacts the care of older patients. It leads to diagnostic errors, inappropriate treatments, or the unjustified refusal of treatment. However, aging and illness are not synonymous, and many seniors remain independent. Combating these biases - particularly through training for healthcare professionals and appropriate policies - is essential to improving the quality of care and changing social perceptions.

A vaccine is a preparation capable of inducing a specific and lasting immune response in the vaccinated patient to protect him in the event of exposure to the pathogen, against infection or to mitigate its consequences. Vaccination during pregnancy has a dual objective: to protect the vaccinated pregnant woman from potentially more severe infections due to pregnancy (flu, Covid-19) and to protect the newborn from birth from potentially serious infections during his first months (whooping cough, respiratory syncytial virus [RSV]). Currently four vaccines are recommended for all pregnant women (anti-flu vaccine, anti-whooping cough vaccine, anti-Sars-Cov-2 vaccine and anti-RSV vaccination). Only live vaccines are contraindicated.On a global and individual scale, vaccination is one of the most effective tools to defend against the infectious world, but the emergence of mistrust of vaccines and variable acceptability of vaccination during pregnancy could threaten its effectiveness.

Cytomegalovirus (CMV), a member of the Herpesviridae family, is the leading infectious cause of congenital neurosensory impairment. This article reviews the key clinical aspects essential for its management during pregnancy and discusses upcoming challenges and future perspectives. In recent years, valacyclovir has demonstrated its efficacy in reducing the risk of maternal-fetal transmission following seroconversion during pregnancy. Based on this evidence, the health-economic evaluation of systematic CMV screening during the first trimester of pregnancy strongly supports its widespread implementation, despite its inability to address secondary infections. Since June 2025, the French National Authority for Health (HAS) has recommended routine screening for CMV infection during the first trimester of pregnancy (for pregnant women whose serostatus is negative or unknown). Emerging antivirals, such as valganciclovir and letermovir, currently under evaluation, could expand treatment options. Finally, research on a vaccine are ongoing, it holds the potential to revolutionize the long-term management of this infection.

Serological testing during pregnancy is an integral part of obstetric monitoring. This screening is essentially based on the detection and dosage of specific antibodies (IgM and IgG) of a virus, bacteria or parasite. Currently in France, 4 serologies are mandatory (toxoplasmosis, rubella, syphilis and hepatitis B) but others are recommended and systematically offered (HIV, HCV, CMV). Determination of immune status should ideally be done in the pre-conception period or as soon as possible after the diagnosis of pregnancy. In the absence of immunity (IgM-, IgG-), hygienic and dietary measures are recommended, and the monitoring methods vary with the pathogen concerned. If seroconversion is suspected (IgM+, IgG+), the patient must be referred to a specialized fetal medicine unit to discuss the need for additional testing and to begin treatment if necessary. If there is any doubt about the interpretation of the serology result, it is essential to refer the patient to a prenatal center or to seek advice from a national reference laboratory.