**Acknowledgements**

In addition, acute and chronic maternal chlamydial infections constitute a significant risk factor for adverse pregnancy outcomes and newborns contagion. Untreated and persistent infections are strongly associated with ectopic pregnancy, which is the tubal development of the embryo and constitute the main cause of maternal mortality in the first trimester of pregnancy in developing countries. In addition, miscarriage, chrioamnionitis, low birth weight, stillbirth, premature rupture of membranes, and preterm birth are frequent pathological consequences of chlamydial infections [51,113,114]. Several mechanisms may contribute to the development of these pathologies, including direct fetal infection, placental damage, and severe puerperal maternal illness [120–124]. Nevertheless, the exact nature of chlamydial infection pathogenesis

CT infections can also be vertically transmitted to newborns during labor, resulting in chlamydial conjunctivitis and/or pneumonia, which may possibly involve similar pathogen‐

Controversial reports point out CT as a risk factor for cervical carcinoma, independent of human papillomavirus [107]. It has been shown that CT interferes with multiple proapoptotic pathways to guarantee survival within host cells [125,126]. In addition, CT activates prosur‐ vival signaling pathways for bacterial nutrient acquisition, expression of antiapoptotic factors, and synthesis of proinflammatory cytokines [127,128]. On the other hand, CT interferes with chromosome segregation and cytokinesis. In consequence, multinucleated cells and cells with aberrant number of chromosomes are often observed in cell cultures infected with CT [129]. Taken together, these findings suggest that persistent chlamydial infections might play a role in the development of cervical neoplasia. Further research is needed to shed light to this issue. The high prevalence and incidence estimates worldwide, in conjunction to the diversity of clinical entities and long-term consequences of chlamydial infections, propel further research of the bacterial and host factors involved in the pathogenesis and damage to the reproductive

**6. Important challenges: Prevention, diagnosis, and treatment of**

The widespread incidence and prevalence of sexually transmitted infections, especially among young population, made them a priority public-health concern worldwide. Screening, control programmes, and education in sexual behavioral aspects and contraception are fundamental for the prevention of chlamydial infections and their long-term sequelae, mainly PID and tubal

Routine screening allows the identification of asymptomatic carriers of CT and contributes to the early detection of chlamydial infections. Appropriated diagnostic services are required to obtain reliable results. The most confident tests for the detection of CT involve nucleid acid amplification techniques that are not available in all laboratories, especially in third-world countries. Nucleic acid amplification tests are more sensitive than culture or antigen tests.

during pregnancy remains unexplained.

146 Genital Infections and Infertility

system.

infertility.

**chlamydial infections**

esis mechanisms to those occurring in the female genital tract.

The authors acknowledge CONICET (PIP), Foncyt (PICT 2116) and UNCuyo grants to M.T.D. for their support in research. They apologize to those investigators whose work could not be cited because of space constraints.
