Clinical Practice Guidelines Antenatal care - Module I

Part C - Areas for Further Research

Page last updated: 02 April 2013

The systematic reviews undertaken to develop these Guidelines identified a number of areas where evidence to support recommendations on antenatal care in the first trimester is limited or lacking. High quality evidence on which to base recommendations about care to meet the specific needs of Aboriginal and Torres Strait Islander women is also limited. This list is not intended to be exhaustive. These areas are listed here with the expectation of encouraging research to further inform practice.

Gestational age assessment

The systematic reviews undertaken to develop these Guidelines did not identify any studies that assessed the use of early ultrasound to estimate gestational age in relation to psychological harms to the mother, risk of over-diagnosis of placenta praevia or its contribution to anxiety. In addition, issues of access need to be studied to ensure that there is equity, especially for women in rural and remote settings and those from marginalised or vulnerable groups.

There is a lack of economic evaluations of the cost effectiveness of ultrasound dating screening. In addition, future research needs to identify reliable indicators to measure how the proposed recommendation might affect rates of first trimester ultrasound screening, number of additional scans and induction of labour in terms of cost, benefit and unintended consequences.

Weight gain in pregnancy

More research is needed on appropriate weight gain or weight loss in pregnancy, particularly for women who start pregnancy at a higher BMI, the effectiveness of routine weighing in improving outcomes, including the impact on women, and interventions that are effective in treating overweight and underweight in pregnancy. More research in this area will guide future practice.

Nausea and vomiting in early pregnancy

While most instances of nausea and vomiting in pregnancy resolve without treatment, many women find nausea and vomiting affect their quality of life. It is currently not possible to identify with certainty interventions for nausea and vomiting in early pregnancy that are both safe and effective. There is also limited research on complementary and alternative medicines that may assist women with these conditions in early pregnancy.

Preterm birth

More research is needed to better understand the high rates of preterm birth experienced by Aboriginal and Torres Strait Islander women, and to identify effective prevention strategies including during the antenatal period.

Hepatitis C

Routine screening of women for hepatitis C remains controversial, particularly as there are no known interventions to reduce the rate of mother-to-child transmission. More research needs to be undertaken into the prevalence of hepatitis C in pregnant women in Australia and the implications of routine screening; in particular, women’s views about screening and the way they will use information about having hepatitis C when there are no preventive transmission interventions.
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There is a need for further research about the prevalence and incidence of Chlamydia infection during pregnancy for different population groups of women, and the acceptability and effectiveness of different approaches to population based screening for chlamydia and other sexually transmitted infections during pregnancy, including for Aboriginal and Torres Strait Islander women.

Asymptomatic bacterial vaginosis

The diagnosis and possible treatment of asymptomatic bacterial vaginosis has been somewhat controversial in the development of these Guidelines. Diagnosis of asymptomatic bacterial vaginosis and its early treatment (before 20 weeks pregnancy) may be beneficial for women with a previous preterm birth. More research needs to identify whether this is the case in Australia and whether there are other benefits or risks associated with screening for this condition.

Vitamin D

As there is limited evidence to support screening of all women for vitamin D deficiency in pregnancy, research in this area is important. Future research needs to identify the predictive factors for vitamin D insufficiency and deficiency in Australia, particularly among Aboriginal and Torres Strait Islander women and quantified for the degree of sunlight exposure including latitude of residence. Research is also needed to identify the potential benefits and risks of supplementation for women who have vitamin D insufficiency compared with those who have a vitamin D deficiency, especially longer term implications for women and their infants. Cost-effectiveness studies of screening and supplementation are also needed.

Women’s experiences of maternal health screening in early pregnancy

These Guidelines recommend a considerable amount of screening in early pregnancy. Some of these tests are commonplace in Australia today while others will provide new challenges to women and health professionals. There is limited research about the benefits, risks and unexpected consequences of screening in pregnancy. Qualitative research is also needed to explore the implications of screening for women, especially those for women in rural and remote settings, Aboriginal and Torres Strait Islander women and women from marginalised or vulnerable groups. The best ways in which to provide evidence based information in a non-judgmental way and to seek informed consent are poorly researched. Understanding of effective ways of providing evidence-based information and effectively enabling input into decision making about care during pregnancy for Aboriginal and Torres Strait Islander women is also limited.

These areas are fundamental to many of the recommendations in these Guidelines and more research into this important area is needed.

Non-prescription and alternative medicines

There is a paucity of high-level evidence about the effects of various non-prescription medicines and other therapies including herbal preparations on the developing fetus and on pregnancy outcome. As their use is widespread there is a need for research into these effects.

Smoking cessation

The cost-effectiveness analysis identified that future health expenditure savings from pregnant women ceasing smoking could be included as benefits. However, there is considerable debate about whether smoking interventions, and preventive measures more generally, reduce long-term health expenditure. The analysis could not estimate future health expenditure savings from pregnant women quitting smoking. This is an important area for future research. Cost-effectiveness analyses are limited in maternity care and this area would benefit from future targeted research to help guide policy and practice.

One of the beneficial interventions identified in these Guidelines is CBT to assist women to quit smoking. However, it is not known how many CBT sessions would be required for a successful quit.

New areas for research

Areas that were not covered in these Guidelines but where research may improve outcomes for women and babies include:
  • optimal methods for providing information to women to promote health in pregnancy;
  • effective models of antenatal care;
  • approaches to contraception, pregnancy planning and preconception care;
  • the validity and acceptability of psychosocial assessment tools for use in specific populations;
  • alcohol use in pregnancy, specifically fetal alcohol syndrome; and
  • screening for thyroid disease in the first trimester.
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