C H A P T E R 11Antenatal screening of the mother and fetus

• The chapter aim s to:– discuss the principles of screening, good

counseling techniques and the potential impact of positive results on women

– describe the currently available screening tests, their aims, and the efficiency of each test

– define what consent is and how the consent process should be undertaken

– provide information regarding how to deal with positive tests and what negative results mean.

Screening principles

• -Screening of a mother and baby is now a major part of care for all pregnancies.

• Treatment should be available and at a stage where the outcome can be changed.

• There should be an appropriate and acceptable test that is available to a defined group, making the screening cost effective in reducing poorer health outcomes.

Definition of screening :

a process of identifying apparently healthy people who may be at an increased risk of a disease or condition, they can then be offered information, further tests and appropriate treatment to reduce their risk and/or any complications arising from the disease or condition.

– When screening for currently unscreened conditions is considered (e.g. Group B streptococcus), it is weighed against these important criteria.

– Screening in pregnancy can be divided into looking for conditions in the mother that, if untreated or undetected, could a ect her health ffor the health of the baby or both, and screening for conditions in the fetus that could impact significantly on the health of the baby.

Limitations of screening (obstacles of screening)

• Screening has important ethical differences from clinical practice as the health service is targeting apparently healthy people,

• Benefits of screening :• 1-offering to help individuals to

make better informed choices about their health.

• 2-it is important that people have realistic expectations of what a screening programme can deliver.

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• While screening has the potential to save lives or improve life through early diagnosis of serious conditions, it is not a foolproof process.

• Equally, some screening is directed at detecting conditions in the fetus that may lead to significant handicap, and to provide prospective parents with choices regarding continuation or otherwise of the pregnancy.

• Screening can reduce the risk of developing a condition or its complications but it cannot offer a guarantee of protection.

• In any screening programme there is a minimum of false-positive results (wrongly reported as having the condition) and false-negative results (wrongly reported as not having the condition).

• Screening can be an emotive issue. While screening for fetal problems is often considered the most emotionally charged area,

• it is important to realize that maternal screening can also raise issues and challenges that all health professionals involved in the service

• Imagine the emotional journey a mother embarks on when faced with a new diagnosis of Human Immunodeficiency Virus (HIV) in early pregnancy.

Social and psychological impact of screening investigations

• Pregnancy is a profound and life-changing event.

• During this time the mother has to adapt physically, socially and psychologically to the forthcoming birth of her child.

• Many women feel more emotional than usual and may have heightened levels of anxiety

• , the increasing availability of fetal investigations has been shown to cause women even greater anxiety and stress.

• Any feelings of excitement and anticipation can quickly change when the mother is introduced to the idea that she is ‘at risk’ of having a baby with a particular problem

• There is evidence that mothers nearing the end of their reproductive years (with ahigher risk of chromosomal abnormality)

• experience pregnancy in a way that is different to younger women.

• Psychologists, sociologists and health professionals now generally accept the finding that high-risk women delay afachment to the fetus until they receive reassuring test results.

• classically termed this the ‘tentative pregnancy’, in a study of women undergoing amniocentesis.

• Anxiety caused by consideration of possible fetal abnormality may be accompanied by moral or religious dilemmas.

• Tests that can diagnose chromosomal or genetic abnormalities also carry a risk of procedure-induced miscarriage.

• Many parents agonize about whether to subject a potentially normal fetus to this risk in order to obtain this information.

• Parents may then need to consider whether they wish to terminate or continue with an affected pregnancy.

• Some religious authorities only support prenatal testing so long as the integrity of the mother and fetus are maintained.

• There are also opposing views about the legitimacy of terminating a pregnancy, even when a serious disorder has been diagnosed.

• Such dilemmas are an unfortunate but inevitable cost of the choices associated with some fetal investigations.

• Despite this, there are important advantages to the acquisition of knowledge about the fetus before birth.

• First, society greatly values the freedom of individuals to choose.

• People are encouraged to accept some responsibility when making decisions about treatment options, in partnership with healthcare professionals.

• A second advantage is that reproductive autonomy may be increased.

• Women can choose for themselves whether they wish to embark upon the lifelong care of a child with special needs.

• This may be viewed as empowering and as a means of preventing later suffering and hardship for child and family alike.

• In summary, prenatal testing is a two-edged sword.

• It enables midwives and doctors to give people choices that were unheard of in previous generations and that may prevent much suffering.

• in some circumstances they actually increase the amount of anxiety and psychological trauma experienced in pregnancy.

• The long-term effects of such trauma on family dynamics are not currently understood.

How screening is set up and the midwife's role and responsibilities

• All midwives need to have a broad understanding of screening investigations because they are responsible for offering, interpreting and communicating the results.

• midwives should work in partnership with women to provide safe, responsive and compassionate care.

• This implies that the midwife as a key public health agent should enable women to make decisions about their care based on individual needs.

• Some midwives specialize in discussing complex testing issues with parents and become antenatal screening coordinators.

• Antenatal and Newborn Screening programmes. has the overall responsibility

• recommends that dedicated screening coordinators oversee the running of screening programmes

• Screening coordinators also provide specialist advice and ensure that there is a line of referral for women whose needs are not met by routine services.

• Screening for pregnant women and newborn babies is now such a complex process that the role of screening coordinator has become a full-time role in most services.

• . As an example, • for screening for hepatitis B states that at least 70% of

pregnant women who are hepatitis B positive should be referred and seen by an appropriate specialist within an effective timeframe (6 weeks from identification).

• -screening for Down syndrome at between 10 weeks + 0 days and 20 weeks+ 0 days states that in 97% of women there must be suffcient information and the woman's correct date of birth, maternal weight, family origin, smoking status and ultrasound dating assessment in millimetres, with associated gestational date and sonographer ID, must be included on the request form.

• All professionals undertaking screening must be appropriately trained and confident in discussing the risks and benefits of all screening programmes