|| B. Allanson, B. Jennings, A. Jacques, A.K. Charles, A.D. Keil, J.E. Dickinson, Infection and fetal loss in the mid-second trimester of pregnancy, Aust N. Z J Obstet Gynaecol, 50 (2010), pp. 221–225 doi: 10.1111/j.1479-828X.2010.01148.x.  D. Baud, G. Goy, K. Jaton, M.C. Osterheld, S. Blumer, N. Borel, et al. Role of Chlamydia trachomatis in miscarriage, Emerg Infect Dis, 17 (2011), pp. 1630–1635 doi: 10.3201/eid1709.100865.  S.K. Srinivas, Y. Ma, M.D. Sammel, D. Chou, C. McGrath, S. Parry, et al. Placental inflammation and viral infection are implicated in second trimester pregnancy loss Am J Obstet Gynecol, 195 (2006), pp. 797–802 DOI: 10.1016/j.ajog.2006.05.049PubMed ID20618237, 21888787, 16949414
||P.2 left column 2nd paragraph: "Miscarriage is one of the most common yet under-studied adverse pregnancy outcomes. It is often defined as the spontaneous loss of pregnancy in the first 22 weeks of pregnancy, although there is no universal consensus on the cutoff used [refs 27, 37, 70]. Early miscarriage occurs in the first 3 months of pregnancy, while late miscarriages occur after three months of pregnancy but before 24 weeks, although definitions vary between countries, local practices and studies [ref 99]. Up to one in five pregnancies ends with an early miscarriage, while late miscarriage (also named second-trimester or mid-trimester miscarriage) is less common and occurs in 1–2% of pregnancies [BNID 113484]. Although the etiology of miscarriage is often unknown, it has been estimated that potentially preventable infections account for up to 15% and 66% of early and late miscarriages, respectively [primary sources]."