Acceptability and feasibility of testing for sexually transmitted infections among pregnant women in Muscat,Sultanate of Oman

Introduction

Chlamydia trachomatis and Neisseria gonorrhoeae are two of the commonest sexually transmitted infections (STIs) in the world. If left untreated, these infections have been associated with adverse maternal and birth outcomes, as well as increasing the risk of HIV acquisition and mother-to-child transmission.^1,2,3

In Oman, as in other countries, diagnosis of STIs is primarily through a syndromic approach that utilises an algorithm to classify symptoms and clinical signs into STI syndromes, and patients are treated with standardised drug regimens without reliance on microbiological tests. ⁴ As a result, little is known about the prevalence of Chlamydia trachomatis or Neisseria gonorrhoeae in the Omani general population. As these infections are often silent, the syndromic approach lacks sensitivity, potentially missing asymptomatic infections and lacks specificity, which can lead to patients unnecessarily exposed to antibiotics.

Notwithstanding sociocultural sensitivities surrounding STIs and religious norms discouraging sex outside marriage, ⁵ the World Health Organisation (WHO) has estimated that for women aged 15–49 years living in the east Mediterranean Region, the prevalence of chlamydia is 3.8% and 0.7% for gonorrhoea with trends indicating an increase in prevalence of both infections since 2012, ⁶ while a recent comprehensive review of genital Chlamydia trachomatis infection in the Middle East and North Africa (MENA) has estimated the prevalence in the general population of 3.0% (95% Confidence Interval (CI) 2.3–3.8). ⁷ Among Gulf Cooperation Council countries, of which Oman is a member state, there has only been one previous study from Saudi vArabia reporting the prevalence of chlamydia of 11.1% (16/144) (as tested by nucleic acid amplification) in a cohort of pregnant women. ⁸

The aims of this study are threefold: to develop and assess a methodological framework for testing STIs in pregnant women in Oman; to evaluate the acceptability and feasibility of STI testing and treatment among this cohort and finally to provide preliminary estimates of the prevalence of chlamydia and gonorrhoea in this setting.

Methods

Results

Acceptability

Over the course of 14 weeks between July and October 2020, we invited 233 pregnant women and recruited 221 (95%) to the study. Reasons for non-acceptance in 12 women included lack of transport (1), not wanting additional testing (1), fear of a positive result (2) and needing to seek permission from their husbands (2); the remaining six did not give a reason. There was no significant difference in the mean ages between the two groups of women (two-tailed t-test p = 0.91, N.S. at p < 0.05). With practice and greater confidence shown by the recruiting team, there was a noticeable reduction in women who declined participation as the study progressed – 8/89 (9%) declined in weeks 1–5 and 0/63 (0%) declined in weeks 10–14.

Table 1 shows the characteristics of pregnant women who participated in the study. Three of 221 women (1.36%) were identified with chlamydial infection (Table 2). There were no cases of gonorrhoea.

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Table 1.

Characteristics of study participants enrolled in the study (n = 221).

Median age/years (IQR, range)	32	(8, 21–46)
Age ranges	n	%
18–24 years	19	9
25–29 years	66	30
30–34 years	61	28
≥35 years	75	33
Nationality
Omani	216	98
Non-Omani	5	2
Marital status
Married (monogamous)	218	99
Married (polygamous)	3	1
Unmarried/divorced	0	–
Highest level of education
None or primary school	12	5
Secondary school	97	44
College or university	106	48
Postgraduate	6	3
Gestational age in weeks, median (range)	26	(8–40)
Pregnancies, median (range)	3	(0–11)
Previous births, median (range)	2	(0–9)
Preconception contraception	n	%
None	95	43
Withdrawal	78	35
Barrier (condom and diaphragm)	14	6
Contraceptive pill	15	7
Copper coil	12	5
Injectable	5	3
Other methods (IUS and patch)	2	1
Current genito-urinary symptoms
None	161	73
1 symptom	53	24
2 or more symptoms	7	3
‘Have you ever been diagnosed with a sexually transmitted infection?’
No	216	98
Yes	3	1
Do not know	2	1
‘Has your partner ever been diagnosed with a sexually transmitted infection?’
No	213	96
Yes	0	0
Do not know	8	4

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Table 2.

Characteristics of pregnant women diagnosed with chlamydia.

Case	Age (years)	Highest level of education	Parity	Marital status	Preconception contraception	Genital symptoms	Previous STI
1	38	University	4	Married (monogamous)	Oral contraception	Vaginal discharge	Genital warts
2	24	Secondary school	2	Married (monogamous)	Withdrawal	None	None
3	34	Secondary school	5	Married (monogamous)	Injectable	None	None

Abbreviation: STI: sexually transmitted infection.

Feasibility

Among all the women who were eligible and consented to participate, 100% were successfully tested for Chlamydia trachomatis and Neisseria gonorrhoeae and given their results by text messaging, the majority within 48 hours. Two were recalled to re-submit urine specimens as their initial samples were volumetrically inadequate. No equivocal results were reported for either infection.

All three women who tested positive for chlamydia were treated; one patient received treatment when she was admitted in labour.

Women were asked about their opinions on STI testing in pregnancy (Table 3), with the majority in favour of tests being routinely offered as part of antenatal care.

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Table 3.

Questionnaire responses to provision of STI testing in pregnancy.

‘What is your opinion on STI tests in pregnancy?’	n = 221	%
a. Should be offered to all women	150	68
b. Should be offered to women at risk	43	19
c. Should be offered only to women who request it	8	4
d. STI testing is not necessary	0	0
e. No opinion	20	9

Abbreviation: STI: sexually transmitted infection.

Discussion

This is the first study conducted in Oman to assess the acceptability and feasibility for pregnant women to undergo rapid screening for gonorrhoea and chlamydia in a busy antenatal clinic based in its capital, Muscat. Using the GeneXpert system, the estimated prevalence of chlamydia in the population of pregnant women from which our study was drawn is 0.97% (95% CI 0–2.62), which is lower than the WHO global estimate of 4.2% and the Saudi Arabia study in pregnant women of 11.1% ⁸ but not significantly different from the regional population estimate for MENA (Figure 1). The low prevalence of chlamydia could be due to conservative cultural and social norms stressing the importance of fidelity in marriage; alternatively, some women may have declined recruitment and testing because they were aware they had STI symptoms or were worried they were at risk. The small number of infections detected in the study and the limited sexual behaviour measures we collected meant that we were unable to examine specific risk factors for infection.OPEN IN VIEWER

Despite initial concerns that STIs are a sensitive sociocultural subject, we were encouraged to find acceptability for STI testing was high. And as measured by the majority of women who received their urine test results within 48 hours of enrolment, rapid intervention was also feasible. Apart from two instances, all enrolled women were able to provide an adequate, self-collected first-catch urine sample on their initial visit.

Women were recruited from a single publicly funded antenatal clinic in Muscat, which provides services for Omani women. As such, this sample may not represent expatriate or Omani women who elect to receive antenatal care from private health institutions. Furthermore, the lifestyles and attitudes of pregnant women living in Muscat may not reflect those living in rural or other communities elsewhere as over 50% of women in our study had received tertiary education. And because Al Wattayah antenatal clinic is a referral centre for complex pregnancies, women <25 years contributed only 9% to the cohort when younger age is a recognised risk factor for acquisition of STIs. Nevertheless, we were justified in recruiting an unselected group of women, irrespective of age or parity, as two of the women with chlamydia were in their mid-30s and multiparous.

While the majority of women found STI testing acceptable (Table 3), given the low prevalence of sexual infections in our study, the potential benefits and cost-effectiveness of testing will require further study in a wider range of antenatal settings.

A further concern, given the relatively low prevalence of gonorrhoea and chlamydia identified in this study, is the possibility of false-positive results from a lower PPV of the test than what we had anticipated. In retrospect, this could have been addressed by ensuring that a positive initial result was confirmed by retesting the sample with an alternative assay. In view of these findings, any future studies in this setting will need confirmatory tests using a different highly specific and sensitive assay. This is especially relevant when dual testing for chlamydia and gonorrhoea because the prevalence of gonococcal infection is lower than the prevalence of chlamydial infection, and the potential for false-positive N. gonorrhoeae results correspondingly greater. ¹⁵

Conclusion

This is the first study in Oman to assess testing of two important STIs in pregnant women. Despite our initial concerns, acceptability and feasibility were high. This exploratory study has helped us evaluate a framework for sentinel surveillance that, with methodological improvements, could be applied to other parts of Oman that may be at higher risk of STIs, as recommended by the WHO Global Health Sector Strategy on STIs (e.g. border towns, communities close to major transport hubs and corridors, as well as areas of social deprivation or high migration). ¹⁶ De-stigmatising STIs and normalising testing behaviour will better identify at-risk populations in Oman and inform policy and programming for culturally appropriate interventions that encompass prevention, treatment and control.

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