Asthma is the most common significant chronic medical condition affecting young adults and it is therefore often encountered in pregnancy. Approximately 3% of women of child-bearing age suffer some degree of asthma and this prevalence is increasing. Some of the apparent increase is due to heightened awareness of the condition, although air pollution and increased childhood exposure to house dust mite may also be contributing.

The haemoglobin disorders are a group of recessively inherited conditions of varying severity. In the homozygous state, alpha zero thalassaemia causes hydrops fetalis, beta thalassaemia usually causes a severe transfusion-dependent anaemia and sickle cell anaemia (HbSS), haemoglobin S/C disease, haemoglobin S/D disease and haemoglobin S/beta thalassaemia cause sickling disorders ranging from quite mild to very severe. Haemoglobin disorders are among the commonest inherited diseases in the UK. Management can be very burdensome, but produces good results in many cases. The disorders can also be prevented by a programme of carrier screening, genetic counselling and prenatal diagnosis in populations at risk. The WHO has defined a “haemoglobinopathy control programme” as an integral strategy combining optimal patient care with prevention based on community education, propective carrier diagnosis, genetic counselling and the offer of prenatal diagnosis. The services required for haemoglobin disorders in the UK have recently been reviewed in a report from the Standing Medical Advisory Committee of the Department of Health. This report focuses on genetic counselling and prenatal diagnosis for haemoglobin disorders.

Although amniocentesis was first reported in 1882, the technique was not in widespread clinical practice until the 1970's. The reason for this slow uptake was that there were few indications for performing the procedure until fetal karyotyping from amniotic fluid cells became possible in 1966. Currently fetal karyotyping is the commonest indication for the technique and amniocentesis has become the mainstay of antenatal diagnosis.

Severe pre-eclampsia is a common disorder in developing countries but still remains a significant problem in developed societies. The management of severe pre-eclampsia in developing countries is frequently hampered by lack of adequate facilities; paradoxically those countries with sufficient resources have a lower incidence of the disease and consequently lack experience in the treatment of severe pre-eclampsia. The management of these patients is further compromised because obstetricians generally lack the necessary knowledge and skills in critical care and conversely critical care specialists may lack appreciation and knowledge of pregnancy physiology and pathophysiology. Patients with severe pre-eclampsia therefore present an interdisciplinary challenge to obstetricians and physicians, who need to be familiar with pregnancy physiology and the current concepts in the pathogenesis and pathophysiology of severe pre-eclampsia. Patients who develop multisystem disease are most appropriately managed by an experienced obstetrician in an obstetric intensive care unit with a physician in consultation.