Direct immunofluorescence for Chlamydia trachomatis on urogenital smears for epidemiological purposes

Hormonal contraceptive use and risk of sexually transmitted infections: a systematic review

Previous research has suggested that hormonal contraceptive users, compared with nonusers, may be at increased risk for acquiring sexually transmitted infections (STIs). We searched the MEDLINE and EMBASE databases for all articles from January 1966 through February 2005 for evidence relevant to all hormonal contraceptives and STIs (including cervical chlamydial and gonococcal infection, human papillomavirus, trichomoniasis, herpes and syphilis). We used standard abstract forms and grading systems to summarize and assess the quality of 83 identified studies. Studies of combined oral contraceptive and depot medroxyprogesterone use generally reported positive associations with cervical chlamydial infection, although not all associations were statistically significant. For other STIs, the findings suggested no association between hormonal contraceptive use and STI acquisition, or the results were too limited to draw any conclusions. Evidence was generally limited in both amount and quality, including inadequate adjustment for confounding, lack of appropriate control groups and small sample sizes. The observed positive associations may be due to a true association or to bias, such as differential exposure to STIs by contraceptive use or increased likelihood of STI detection among hormonal contraceptive users.

Chlamydia trachomatis and oral contraceptive use: a quantitative review

OBJECTIVES

Chlamydia trachomatis is now recognised as a major sexually transmitted disease; oral contraceptive use is rapidly increasing particularly in developing countries. There are thus important public health implications of the many reports that isolation of C trachomatis is more frequent among users of oral contraceptives. The aim of this analysis was to assess the strength and consistency of this association by summarising published studies between 1972 and 1990.

DESIGN

Studies identified were grouped according to whether they were prospective or case-control studies. Data were extracted and pooled estimates of the unadjusted odds ratios were made for all studies, as well as for sub-groups defined by an index of study quality, background prevalence of C trachomatis, and the contraceptive comparison being made.

LOCATION

Studies in the analysis were mainly conducted in Europe and North America; the meta-analysis was done at the Harvard School of Public Health, Boston, MA, USA.

RESULTS

The pooled estimated unadjusted odds ratio for 29 case-control studies examined was 1.93 (95% CI, 1.77-2.11), indicating an almost twofold increased risk of chlamydial infection for oral contraceptive users. Neither study quality nor prevalence of C trachomatis modified this risk. When compared to the use of barrier contraceptives, however, the risk of infection for women using oral contraceptives increased to 2.91 (95% CI, 1.86-4.55). The pooled estimated protective effect of barrier methods in these studies was 0.34 (95% CI, 0.22-0.54).

CONCLUSIONS

Cross-study comparisons of the relationship between oral contraceptive use and chlamydial infection are limited by the design and analysis of many component studies which did not control for confounding factors such as sexual behaviour and age. The almost twofold risk of increased chlamydial infection for oral contraceptive users, supported by the findings of two prospective studies, however, points to the importance of considering the risks and benefits of oral contraceptive use in women who are likely to be exposed to C trachomatis and other STDs. The protective effect of barrier methods emphasizes the continued need for promoting barrier methods of contraception.

Epidemiological aspects of chlamydial infections and tubal abnormalities in infertile couples

Demographic and behavioural data on parameters of previous sexual behaviour were collected of both partners of 184 couples visiting the Department of Obstetrics and Gynaecology because of infertility. They were also screened for urogenital infection with Chlamydia trachomatis. Of 131 (71.2%) women, a diagnosis was established by hysterosalpingography and/or laparoscopy about the condition of their fallopian tubes. An unmarried status correlated significantly with a history of sexually transmitted disease, and with past promiscuity of male and female partner. Abnormalities of the fallopian tubes were significantly related to an unmarried status, a history of pelvic inflammatory disease, and past promiscuity. Male promiscuity was not shown to correlate with tubal abnormalities in the female partner. In only three couples, the partners reported to have had a sexual relationship with a partner other than the current one over the past year. The percentage of Chlamydia trachomatis-positive women of 1.8 and men of 3.0 in our study agrees with this low recent promiscuity. Chlamydia trachomatis was shown to be able to maintain itself for at least 4 years within a couple. The results are commented on.

Pelvic inflammatory disease: the influence of contraceptive, sexual, and social life events

In order to determine associations between pelvic inflammatory disease (PID) and contraceptive, sexual, and social life events, 620 Danish women aged 15-54 were invited to participate in an in-depth interview. Of 585 participating women, 459 were consecutive gynecological in- or outpatients, and 126 were randomly selected from visitors in general practice. Data were analyzed by multivariate test statistics. The mean number of PIDs thereby retrospectively assessed was 1.0. Two-thirds had never had PID, one third had had on average 3 PIDs. The sexual parameter which had the highest predictive value for later PID was the coital debut. Women with coital debut before the 16th year had double the number of PIDs, as women with sexual debut at age 18 or later. Likewise, the mean coital frequency was positively correlated to the number of PIDs. The number of sexual partners, on the other hand, was merely a risk-indicator without a direct influence on PID. Women who used barrier methods (condom and/or diaphragm) for 2 years or more had 23% fewer PIDs than women who had used barrier methods for less than two years. The small number of PIDs among women at high socioeconomic levels could be explained alone by a later coital debut and longer use of barrier methods than that among women at low socioeconomic levels.

Is serology of any use when searching for correlations between Chlamydia trachomatis infection and male infertility?

Evidence on Chlamydia trachomatis causing male infertility is conflicting. We therefore collected data on epidemiological and clinical correlates of chlamydial infection and male fertility in 184 males visiting our Fertility Unit. Antibodies against Chlamydia trachomatis in serum and semen were also determined. Significant correlations were demonstrated between current chlamydial urethral infection and semen immunoglobulin (Ig) A, serum IgA and serum IgG. These parameters, however, were neither related to a history of sexually transmitted disease nor to lifetime number of sexual partners. Why, in the male, serology does not correlate with chlamydial infection in a more remote past is explained. Our data support, on epidemiological as well as serological grounds, the conclusion that chlamydial infection probably does not contribute significantly to male infertility.