8 Preconception care
CASE STUDY: ‘I’m thinking of getting pregnant soon.’
Jan’s medical history was essentially normal. She had been on the COCP since the age of 16 with no particular problems. She did smoke, however. The GP pulled out a ‘preconception care checklist’ and went through each item with Jan. The GP gave her some advice about smoking cessation, ordered rubella and varicella serology to check Jan’s immunity and advised her to continue taking the pill until the results came back. The GP then went over some reproductive physiology and explained to Jan when peak fertility occurred and how to recognise it by becoming aware of changes in mucus.
Together the GP and Jan decided she would discontinue the COCP in 3 months. She would commence taking folate supplementation straight away and would use condoms for the first month or two after discontinuing the pill in order to learn when and if she was ovulating. When the consultation was over the GP appreciated how Jan’s presentation specifically for preconception advice had provided an opportunity to discuss preconception issues in a structured fashion. The GP made a note to let women attending her practice know about the need for and availability of preconception care by encouraging them to make an appointment before they stopped using their contraception.
Preconception care is essentially ‘risk management’ and aims to identify and modify biomedical, behavioural and social risks to a woman’s health or pregnancy outcome through prevention and management. It involves health promotion, screening, and interventions aimed at reducing risk factors that might affect future pregnancies. These steps should be taken before conception or early in pregnancy in order to have a maximal effect on health outcomes.1
The provision of preconception care can also increase pregnancy planning.2 This is important because planned pregnancies typically have improved outcomes for both women and infants, and we know that approximately half of all pregnancies are unplanned.3 In addition, 52%4 of women who have a negative pregnancy test in the general practice setting have a medical risk factor that could adversely affect a future pregnancy.
Nearly all women realise the importance of optimising their health before pregnancy and know that the best time to receive information about pregnancy health is before conception. The vast majority of women prefer to receive information about preconception health from their primary care physician, yet in one survey only 39% of women could recall their physician ever discussing this topic.5
GPs can make a difference, however, by providing counselling to women before they get pregnant and even before they think about getting pregnant. They can do this by introducing the concept and availability of preconception care to women when they present for contraception, Pap smears or other reasons, and inviting them to return when they are ready to conceive but before ceasing contraception.
There are a number of issues that GPs should address during preconception counseling (see the preconception care checklist in Box 8.1). GPs can go through the issues raised in the checklist with the woman and reinforce them with brochures and information to take home. Once a GP ascertains that preconception care is relevant for the patient, a convenient way to utilise the checklist and structure the care is to take the history and order the relevant screening tests at the initial consultation, and then to discuss the results, vaccinate if necessary and provide lifestyle and any medical advice that is required at the second consultation.
BOX 8.1 Preconception care checklist
Research suggests that many women have clear aspirations with regard to parenthood by their late teens or early 20s.6 About 92% of women express a desire to have one or two children within the confines of a stable relationship by the age of 35,7 with only 6–8% of Australian women aspiring to childlessness.8
There is, however, a significant gap between the number of children women tell researchers they want and those they achieve. It is this gap, between women’s fertility aspirations and their fertility attainment, that explains much of our sustained low fertility rates and resulting predictions that a quarter of women will end their fertile years childless. In other words, while some of our low fertility rates can be explained either by infertility or by women making autonomous choices to remain childless, the remainder are the result of circumstances constraining women’s freedom to choose motherhood, not choice.6
The average age of Australian first-time mothers has risen from 25 in 1991 to nearly 30 in 2003.9 This trend, repeated in other Western countries, has been labelled the ‘epidemic of pregnancy in middle age’.10 Female fertility declines with increasing age. Age-related fertility problems increase after 35 and dramatically after 40.10 For those who do fall pregnant later in life, there are associated adverse outcomes to deal with. Pregnancies in older women are more likely to result in adverse outcomes, with increased rates of stillbirth, miscarriage and ectopic pregnancy,11 as well as multiple births and congenital malformations.12 Pregnancies in women older than 40 years are associated with more non-severe complications, premature births and interventions at birth.13 Levels of pregnancy disease are increased, and older mothers are more likely to experience severe morbidity.14
Women are ill-informed about the relationship between age and infertility. In the USA, 88% of women overestimated by 5–10 years the age at which fertility begins to decline.15 An Australian study of women aged over 35 seeking assisted reproductive technology (ART) found that 18% were unaware of the impact of age on infertility.16
In addition, women are misinformed about the efficacy of ART, overestimating their chance of having a baby using these techniques.17 This belief in the ability of ART to overcome the ‘biological clock’ and achieve a pregnancy in most women and at almost any age is ill-founded.18
Fecundity declines gradually but significantly, beginning approximately at age 32 years, and decreases more rapidly after age 37 years, reflecting primarily a decrease in egg quality in association with a gradual increase in the circulating level of follicle-stimulating hormone.19 There is a 50% decrease in apparent fecundability at the age of 35 years20 (Fig 8.1). Another way of expressing this to patients is that while 71% of patients aged 30 will conceive within 3 months, only 41% of those aged 36 will conceive within 3 months.21
GPs should advise that from a medical point of view the ideal is to have the first child by 30, as fertility declines with age and the risk of fetal abnormality increases with age, as shown in Figure 8.2.
Whereas most women are being made aware of the availability combined first-trimester screening for Down syndrome (regardless of age), women also need to know that their ethnicity and family history may mean that they could be a carrier of a genetic disease. GPs should explore with the patient and her partner whether there is a family history of birth defects or mental retardation, haemoglobinopathies (thalassaemia in those of Mediterranean heritage and sickle cell disease in African-Americans), cystic fibrosis, Tay-Sachs disease, phenylketonuria, cystic fibrosis or congenital hearing loss.
Table 8.1 explains the genetic inheritance associated with some genetic diseases and Table 8.2 gives the carrier frequency and incidence of some of the conditions for which genetic screening can be offered.
• If both parents are carriers of an autosomal recessive condition, there is a 1:4 (25%) chance that each child will be affected.
• Because females have two X chromosomes, mutations in X chromosome genes cause mild or no manifestations in females but fully manifest in males who have only one X chromosome.
(From Delatycki and Massie56)
Complications that have occurred in previous pregnancies, such as those listed in Box 8.2, may recur in subsequent pregnancies. Identifying these issues and looking for causative or contributory factors may assist in preventing them from occurring in subsequent pregnancies or at least minimise their impact when prevention is not possible.
It is also important to consider whether there is a history of polycystic ovary syndrome, endometriosis, previous ectopic pregnancy or sexually transmissible infections (STIs), as these conditions might put the woman at risk of delayed fertility or infertility.