Pregnancy is a physiological condition that affects all organs. Diseases unrelated to pregnancy may present coincidentally during pregnancy or may be exacerbated by pregnancy, and may increase maternal and/or fetal morbidity or mortality. Compared with many other systems, the changes within the biliary tree and pancreas are relatively minimal. However, pregnancy is associated with an increased likelihood of cholelithiasis, which can have significant implications for the parturient.

Women with epilepsy constitute about 0.6% of pregnancies. The potential for major structural malformations following gestational exposure to anti-epileptic drugs (AEDs) is well known and causes concern as how best to manage epilepsy during pregnancy. In this review we focus on the structural and functional effects on the developing brain to complement other recent reviews. We do not cover neural tube defects which have been reviewed elsewhere. Suffice to say that carbamazepine, lamotrigine and, in particular, valproate exposure are associated with them. We discuss studies based on animal models as well as those that have followed-up children exposed to AEDs in-utero. Careful longitudinal human research can document the cognitive and behavioural effects, but the long time scales required and inability to rule out confounding variables, both genetic and environmental, are serious limitations. Animal studies are based on the assumption that many developmental processes are conserved between the animals used in the models (most often rodents) and humans. However, the hugely expanded cortex and cognitive and behavioural repertoire of humans implies that there are aspects that can not be well modelled. In addition, due to differences in how susceptible different species are to various teratogens, studies always need to be done in man as well. Nevertheless, an understanding of the molecular mechanisms of neuro-teratogenesis derived from animal models will help us predict which anti-epileptic drugs are likely to cause fewer neuro-developmental problems in humans.

Invasive prenatal testing, amniocentesis and chorionic villus sampling, has been used for over four decades to identify fetal genetic disorders. The most common test after obtaining fetal tissues is chromosome analysis, performed for a variety of medical indications including abnormal ultrasound findings, advanced maternal age and an abnormal screen for Down syndrome. About 2% of pregnancies in women over the age of 35 will show a chromosome abnormality, with trisomy 21 being the most common. In addition to Down syndrome, the most commonly observed trisomies are those of chromosomes 13 and 18. Numerical abnormalities of the sex chromosomes are also relatively common, as well as triploidy.

The World Health Organisation (WHO) has estimated that 1500 women die every day from preventable complications of pregnancy and childbirth. While barriers to accessing healthcare are undoubtedly multi-factorial, studies have repeatedly shown that providing skilled healthcare workers can result in untold benefits for women and babies in developing countries. The phenomenon of preventable maternal and fetal morbidity and mortality is not limited to the developing world. The Confidential Enquiries into Maternal Deaths (CEMD) and Stillbirths and Infant Deaths (CESDI) in the UK have repeatedly identified substandard care as a major contributor to maternal and neonatal mortality. In 2008 The King's Fund published Safe Births: Everybody's business, an independent enquiry into the safety of maternity services in England. This recommended that simulation-based training to assess clinical, communication and team skills should be available to all maternity staff, and that training should form a core activity. Many hospitals in the UK have been running in-house courses for staff for over a decade with measurable improvements in neonatal outcomes. The value of these training schemes is recognised and rewarded through reduced insurance premiums for participating hospital trusts as part of clinical negligence schemes. Gaining competence in managing obstetric emergencies presents particular challenges for trainees. Most emergencies are, thankfully, uncommon but some constitute life-threatening events where management naturally falls to the most experienced available clinician. The skills required are often particular to emergencies and therefore novel to trainees. Utilising emergencies as training opportunities is further complicated by the presence of a conscious patient.