Correspondence:
Community Medicine Department,
College of Medicine, Mansoura University,
Mansoura 35516 - Egypt
e-mail: ahgilany@gmail.com
Mobile: 0020160714481

INTRODUCTION

Routine ultrasound examination has quickly become a social event that provides the first feeling of real contact with the new family member.¹ It has become an almost universal feature of prenatal care in most countries with developed health services.^2,3 As ultrasonography during pregnancy is widely practiced in both developing and developed countries and is used on every pregnant woman, a comment on this diagnostic tool in the light of routine antenatal care is warranted. There is no doubt that real-time ultrasound applied with most advanced apparatus gives detailed physical information about the foetus e.g. confirmation of the term date, detection of malformation, twins, foetal sex and placenta previa. However, routine ultrasound evaluation is not recommended and there has been controversy surrounding the use of ultrasound as part of routine antenatal care.^4,5 Although there is no reliable evidence of physical harm to human foetuses or their mothers from diagnostic ultrasound imaging, public health experts, clinicians and industry representatives agree that causal use of ultrasonography, especially during pregnancy should be avoided. Viewed in this light, exposing the foetus to ultrasonography with no anticipation of medical benefit is not justified and obstetric ultrasound should only be done for medical reasons, and exposure should be kept as low as reasonably achievable.^6-9 The issue of safety of ultrasound in pregnancy is a subject of continuous vigilance. Safety statements are regularly issued and updated.¹⁰ There is no scientific data available to support improved foetal outcome as a result of routine ultrasound.³
In the current Saudi practice according to the Ministry of Health guidlelines, antenatal mothers should be routinely examined by ultrasound twice, the first between 16 and 18 weeks gestation and the latter between 34 and 36 weeks to ensure their wellbeing. The technique used is two dimentional real-time ultrasound.^11,12 If not available at the local primary health care centre, mothers were referred to a nearby health centre or hospital for a scan.
There is little data about the utilization of PNU examination in Saudi Arabia. The objectives of this study were to determine the frequency of PNU and its differential in Al-Hassa, Saudi Arabia.

This study was carried out in Al-Hassa, Saudi Arabia, during a period of six months from the first of January to the end of July 2008 G. All mothers of registered births during the study period were the target population.
Two-stage stratified sampling technique was used. The first stage is stratification of Al-Hassa into urban, rural and Hegar (Bedouin desert collections) areas. At the second stage, 15 out of 47 primary health care centres (PHCCs) in the region (five centres from each stratum) were chosen.

Mothers gave a verbal consent to participate in the study. They were assured that data collected will be dealt with confidentially and the impact of the study will be respected, maintained, and used only for research purposes and for improving services.
In each PHCC an Arabic speaking female nurse completed questionnaires by interviewing mothers during birth registeration (within two weeks of birth).
Questionnaire included mothers' residence, age and gravidity; source of prenatal care as well as the list of high risk pregnancies that is used during routine prenatal care.
Data were analyzed using SPSS (Statistical Package for Social Sciences) version 11. Descriptive statistics were done. The non-parametric Mann-Whitney test was used for comparison between groups. P=0.05 was considered statistically significant.

During the study period 2,103 live births for 2,084 mothers were registered at the chosen PHCCs. A total of 2,067 (99.2%) mothers were interviewed and 2,039 (98.6% of the interviewed) received at least one prenatal care visit, whatever its source. Thus 1.4% of mothers never received prenatal care and subsequently no PNU examination during the index pregnancy.
Table (1) shows that among 2,039 mothers who received prenatal care, 94.6% underwent PNU at least once with a mean and median of 2.37 and 2.0, respectively. Of these mothers 35.7%, 24.1% and 19.2% underwent one, two and three or more PNU examinations, respectively. Thus among interviewed mothers 158 (7.6%) never received PNU (28 never received prenatal care and 130 received prenatal care without PNU examination).
Table (2) reveals that the mean number of PNU examinations was significantly higher among urban mothers, mothers aged more than 35 years and those seeking prenatal care at sites other than primary health care centres (private, hospital and shared care).

Table 1: Distribution of 2,039 mothers who received prenatal care according to PNU examination

Table 2: Variation of PNU examination by some maternal characteristics among mothers who received prenatal care

PHCCs= Primary Health Care centres
# Private clinics (650), Hospitals (66) and shared care (85)
a & b significant difference between the corresponding groups by Mann-Whitney test

Ultrasound is an excellent means of assessing foetal well-being; however, it can be inappropriately used, leading to excessive reliance on technology and increasing health care costs. Consequently, it is crucial to know the indications for ultrasound, its true value and limitations. There is a scarcity of published data on the frequency of PNU in Saudi Arabia. Our study adds to the literature and provides a snapshot of the frequency of use of PNU in one region of Saudi Arabia.
In our study, 92.4% of interviewed mothers received at least one PNU examination during the index pregnancy. More than one-third (35.7%) of mothers who received prenatal care, had only one PNU scan. On the other hand, one-third of them received three or more PNU scans. Previous studies in other regions of Saudi Arabia reported that 57.6% and 52.6% of mothers attending PHCCs received PNU at least once. Furthermore, only 8.9% of them received two or more PNU.^13,14 In Western countries, about 80% of pregnant women have at least one ultrasound during the pregnancy.8 In rural Canada 97.1% of women underwent at least one PNU, 84.5% underwent at least two and 30.1% had three or more.¹⁵ In USA at least one PNU was performed during 89% of pregnancies in 2004 compared to 67% in 2000 and 70% in 2002.^16,17
Each woman seeking prenatal care, received 2.37 PNU scan on average with a range of 0 to 18. This is much higher than the averge of 1.2 scans among mothers attending PHCCs for prenatal care in another region of Saudi Arabia.¹⁴ In Canada, PNU use is increasing rapidly and for 1989-90 averaged 2.19 scans per delivery in Ontario and 1.75 in British Columbia, up from 1.06 and 0.88 in 1981-82, respectively. In a later study in Western Labrador of Canada, the average was 2.16 scans per delivery (range 0 to 7).^15,18 In Malta, an average of 2.6 PNU were performed on every pregnant mother.¹⁰ A relatively recent study in USA revealed an average of 3.5 PNU scans per singleton delivery.¹⁶
Among women seeking prenatal care, the mean number of PNU scans was significantly higher among urban mothers than rural and Hegar mothers. This is explained by the availability of ultrasound at private clinics, hospitals and PHCCs in the urban areas. This is supported by the finding that mothers who received prenatal care at private clinics or hospitals showed a significantly higher use of scans than those of PHCCs. An important finding is that the average number of PNU scans did not differ according to gravidity or risk status of pregnancy. This indicates that PNU scan is performed routinely, irrespective of the risk status. The same finding was reported in rural Canada.¹⁵
We cannot comment on what proportion of the scans reported in this study were medically indicated, furthermore gestational age at scanning cannot be ascertained.
We suggest more judicious use of PNU, according to quality assurance and current evidence-based guidelines. Routine use of third and above PNU for non risky pregnancies should be discontinued in favour of its use by clinical indication only.
Despite its limited scale, this study has identified issues for future research in routine use of PNU. A wide-scale national study is warranted to highlight medical indications, timing and women's attitude and perception of ultrasongraphy during pregnancy.

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