Dyspnoea is a common complaint in pregnant women, and may occur as a result of the physiological changes in pregnancy or due to cardio-respiratory disease. A prospective observational study of 62 pregnant women identified that 76% experienced dyspnoea at some point during their pregnancy. Approximately half became symptomatic before 20 weeks’ gestation and the incidence increased until about 30 weeks’ gestation. It is important to be aware that some complications of pregnancy may produce dyspnoea in the previously well patient, so it is important to differentiate pathological conditions from this physiological dyspnoea. This chapter reviews the mechanisms of dyspnoea of pregnancy and the differentiation from pathological conditions.

Venous thromboembolism (VTE), which manifests as deep venous thrombosis (DVT) and pulmonary embolism (PE), is a major cause of maternal morbidity in developed countries, with an estimated overall incidence of 12.1 per 10 000 and 5.4 per 10 000 pregnancies, respectively.

Prescribing in pregnancy and breastfeeding requires a thoughtful approach, considering maternal, fetal and neonatal physiology, and the pharmacokinetics of the prescribed drug. This chapter aims to familiarize the reader with pregnancy-related issues that should be taken into account when prescribing medications in the peri-partum period.

Pulmonary assessment during pregnancy is similar to that of the non-pregnant patient. During pregnancy, there are a number of new symptoms, many of which are physiological, but others may be of more concern. The anatomical and physiological changes can result in changes which overlap with those seen in disease. Respiratory symptoms may arise from pregnancy-specific conditions such as pre-eclampsia or peripartum cardiomyopathy. Pregnancy can also increase the risk of conditions like thromboembolism and exacerbate pre-existing conditions like asthma.

Before prescribing in pregnancy it is important to understand the potential pharmacodynamic and pharmacokinetic changes of medications related to physiological changes in pregnancy, e.g. increased plasma volume, increased renal excretion, and also the bioavailability of the medication to the mother, fetus and infant through breastfeeding.

Restrictive lung diseases are conditions characterized by a reduction in lung volume, and may be subdivided according to the anatomic location of the pathology. Diseases of the lung parenchyma itself reduce lung volumes due to the poor compliance (‘stiffness’) of the lungs. Examples include interstitial lung diseases such as pulmonary fibrosis, connective tissue diseases affecting the lung, sarcoidosis and hypersensitivity pneumonitis. A second anatomic group involves diseases of the chest wall, where lung volumes are reduced by abnormalities of the lining of the lung (pleural thickening), the skeletal chest wall (e.g. marked kyphoscoliosis) or weakness of the muscles generating breathing activity (e.g. neuromuscular diseases).

Oxygen was employed in the acute care setting for the first time in 1885; but it was not until the twentieth century that discoveries related to its physiological effects and technological advances enabled its clinical application.

Pleural disease in pregnancy most often results in pleural effusions or pneumothorax. Pregnancy-related medical conditions or disease exacerbated by pregnancy will be discussed in this chapter. Pleural effusions are varied in etiology requiring discussion of specific forms of effusions.

Multisystem physiological changes in pregnancy are designed to provide for the increase in metabolic demand from the growing fetoplacental unit, the developing uterus and other maternal adaptations. Basal oxygen (O2) consumption increases by 50 ml/min or about 25% at term gestation, and basal metabolic rate increases similarly. There is further increased oxygen consumption during labour and vaginal delivery. Global O2 delivery is determined by the O2 carrying-capacity of arterial blood and cardiac output.

Amniotic fluid embolism syndrome (AFES) is one of the most devastating and catastrophic events unique to pregnancy that can occur during gestation, during labour and delivery, or in the immediate post-partum period. It is a frustrating and complex disease for the practitioner since there is significant variability in its clinical presentation. The incidence and frequency of the disease are also variable because of the lack of firm and established diagnostic criteria.

Asthma is a heterogeneous disease defined by various respiratory complaints and can present in all age groups. Its hallmarks are variable airflow limitation and chronic airway inflammation. With disease progression, the variability in airflow limitation can become irreversible.

The focus of this chapter is on the most common type of tobacco use – cigarette smoking (smoking) – which involves burning tobacco and inhaling the products of this combustion. There are many other tobacco products that can be smoked and also some that involve tobacco use without burning, such as by ingestion or vapour inhalation. Tobacco products that can be smoked include cigarettes (manufactured or hand-rolled), cigars and loose tobacco used in pipes and waterpipes. Ingested (also called ‘smokeless’) forms of tobacco are generally intended for oral use and are sucked, chewed (dipped), gargled or applied to the gums or teeth, and fine tobacco mixtures can be inhaled into the nostrils (snuff).

Acute respiratory failure is a rare occurrence during pregnancy, estimated to occur in 0.2–0.3% of pregnancies, but when this occurs it can have significant consequences for mother and child. Acute hypoxic respiratory failure associated with pregnancy requires attention to the inciting cause and distinction between cardiogenic and non-cardiogenic aetiologies. Specifically, acute respiratory distress syndrome (ARDS) is characterized by rapid onset of hypoxaemic respiratory failure associated with diffuse pulmonary opacities related to non-cardiogenic pulmonary oedema.

The importance of the accurate recording and monitoring of the occurrence of disease is well recognized. There is a long history of the establishment of disease registers and this is also the case for congenital anomaly registers. This chapter provides an overview of 2 congenital anomaly register networks, focusing on factors that lead to the successful operating of a register and the main uses of their data.

Twin-twin transfusion syndrome (TTTS) complicates 10–15% of monochorionic twin pregnancies. In the majority of cases, and for still unexplained reasons, the condition usually presents between 16 and 26 weeks’ gestation. When left untreated, mid-trimester TTTS carries a very high mortality rate, either due to preterm birth as a result of the ever-present polyhydramnios [1], or due to fetal death as a result of cardiac failure [2,3].