ArticlesChlamydia trachomatis and the risk of spontaneous preterm birth, babies who are born small for gestational age, and stillbirth: a population-based cohort study
Introduction
Worldwide, chlamydia is one of the most common sexually transmitted infections, with an estimated 131 million new cases annually.1 Although genital infections are thought to contribute to the incidence of adverse obstetric outcomes such as spontaneous preterm birth and stillbirth,2 there are insufficient data regarding the role of chlamydia infections in these outcomes. To our knowledge, there are no published randomised controlled trials of the effects of chlamydia screening in pregnancy on obstetric outcomes.3 Furthermore, randomised placebo-controlled prevention trials of antibiotics (including azithromycin) given during the antenatal period to high-risk women have found no effect on the incidence of preterm birth.4 Findings from observational studies have been inconsistent: most studies5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 but not all16, 17, 18, 19, 20, 21, 22 suggest that chlamydia infection increases the risk of preterm birth. There is similar discordance in studies examining the effects of chlamydia infection on birthweight and stillbirth.9, 23
There are many possible explanations for the discrepancy in findings between published observational studies. These explanations include small numbers of events in these studies, which might have led to random error; inconsistency in the type of chlamydia test used (serology, culture, or nucleic acid amplification); variations in the outcome definition and ascertainment; use of case-control designs in which control populations might not be well matched; inadequate control of potential confounders, including other genital tract infections or other factors known to result in adverse obstetric outcomes, such as smoking during pregnancy; and the potential for publication bias. In this analysis, we used a large cohort of women with records of laboratory chlamydia tests and test positivity, and we used reliable ascertainment of obstetric outcomes to examine the effects of chlamydia infection on the risk of spontaneous preterm birth and other adverse birth outcomes.
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Study design and population
A cohort comprising women of reproductive age residing in the Australian state of Western Australia (WA) was constructed by probabilistically linking two whole-population administrative datasets: birth registrations, which contain a record of all children born and registered in WA from 1974 onwards, and the WA electoral roll. Electoral enrolment is compulsory for Australian citizens, with an estimated 92% of the eligible population included on the roll in WA.24 Eligible women were all those
Results
We identified 101 558 women aged 15 to 38 years in the cohort with a first record of a singleton birth between 2001 and 2012. Of births that could be classified, 3921 (3·9%) of 101 558 women had a spontaneous preterm birth, 9762 (9·6%) of 101 371 births were small for gestational age, and 682 (0·7%) of 101 558 infants were stillborn (table 1).
Table 1 shows the characteristics of the mothers, grouped according to obstetric outcomes. Generally, women with each of the adverse obstetric outcomes
Discussion
This large population-based cohort study analysed more than 20 000 women with laboratory testing data on chlamydia positivity during pregnancy. In more than 900 spontaneous preterm births and more than 2500 babies who were small for gestational age, we found no increase in the risk of having a spontaneous preterm birth or a baby that was small for gestational age among women with a positive chlamydia test during pregnancy. Although there were fewer cases, we also found no evidence to suggest an
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2021, EClinicalMedicineCitation Excerpt :Because over 70% of CT infections in women and 50% in men are asymptomatic [8], effective control of the infections often relies on screening for CT followed by treatment of the infected cases. Benefits of CT screening in women have been demonstrated a reduction in rates of PID [9], and prevention of adverse obstetric outcomes among pregnant women [10,11]. Screening for CT is largely subject to the tests available and accessible to the target populations.
Sexually transmitted infections in pregnancy – An update on Chlamydia trachomatis and Neisseria gonorrhoeae
2020, European Journal of Obstetrics and Gynecology and Reproductive BiologyCitation Excerpt :West and Central Africa pooled prevalence estimates for CT and NG were 6.1 % (95 % CI 4.0 %–8.3 %) and 2.7 % (95 %CI 1.7 %–3.7 %), respectively. Individual studies of CT and NG prevalence among pregnant women in other WHO regions are as follows: Western Pacific (Australia, Papua New Guinea, Mongolia, Japan) CT 1 %–22.9 %, NG 0.1–14.2% [59–68]; Southeast Asia (Thailand, India) CT 1.6–18.8 %, NG 0% [50,69,70]; Europe (Portugal, Italy, Netherlands, Finland) CT 1.9 %–11.8 %, NG 4.9 % [71–74]; the Americas (USA, Brazil, Mexico, Haiti, Argentina, Chile) CT 5.9 %–14.8 %, NG 0 %–7.1 %. [39,47,75–84]. Studies in the Eastern Mediterranean region (Iran) suggest CT prevalence of 6.7 %–27.6 % and NG prevalence of 1.3 % [85–88].
Maternal, obstetric and gynecological factors associated with preterm birth in Rwanda: findings from a national longitudinal study
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