- Section 1 Patients and their treatment
- Section 2 Background to medicine
- Section 3 Cell biology
- Section 4 Immunological mechanisms
- Section 5 Principles of clinical oncology
- Section 6 Old age medicine
- Section 7 Pain and palliative care
- Section 8 Infectious diseases
- Section 9 Sexually transmitted diseases
- Section 10 Environmental medicine, occupational medicine, and poisoning
- Section 11 Nutrition
- Section 12 Metabolic disorders
- Section 13 Endocrine disorders
- Section 14 Medical disorders in pregnancy
- 14.1 Physiological changes of normal pregnancy
- 14.2 Nutrition in pregnancy
- 14.3 Medical management of normal pregnancy
- 14.4 Hypertension in pregnancy
- 14.5 Renal disease in pregnancy
- 14.6 Heart disease in pregnancy
- 14.7 Thrombosis in pregnancy
- 14.8 Chest diseases in pregnancy
- 14.9 Liver and gastrointestinal diseases of pregnancy
- 14.10 Diabetes in pregnancy
- 14.11 Endocrine disease in pregnancy
- 14.12 Neurological conditions in pregnancy
- 14.13 The skin in pregnancy
- 14.14 Autoimmune rheumatic disorders and vasculitis in pregnancy
- 14.15 Maternal infection in pregnancy
- 14.16 Fetal effects of maternal infection
- 14.17 Blood disorders in pregnancy
- 14.18 Malignant disease in pregnancy
- 14.19 Maternal critical care
- 14.20 Prescribing in pregnancy
- 14.21 Contraception for women with medical diseases
- Section 15 Gastroenterological disorders
- Section 16 Cardiovascular disorders
- Section 17 Critical care medicine
- Section 18 Respiratory disorders
- Section 19 Rheumatological disorders
- Section 20 Disorders of the skeleton
- Section 21 Disorders of the kidney and urinary tract
- Section 22 Haematological disorders
- Section 23 Disorders of the skin
- Section 24 Neurological disorders
- Section 25 Disorders of the eye
- Section 26 Psychiatric and drug-related disorders
- Section 27 Forensic medicine
- Section 28 Sport and exercise medicine
- Section 29 Biochemistry in medicine
- Section 30 Acute medicine
(p. 2687) Blood disorders in pregnancy
- Chapter:
- (p. 2687) Blood disorders in pregnancy
- Author(s):
David J. Perry
, and Katharine Lowndes
- DOI:
- 10.1093/med/9780198746690.003.0279
Plasma volume increases by more during pregnancy than does red cell mass, leading to haemodilution and a fall in the haematocrit from about 40% to 33%, with a nadir usually reached at 24–32 weeks’ gestation. Anaemia during pregnancy is defined as a haemoglobin concentration of below 105 g/L during the second and third trimesters and below 110 g/L in the first trimester. The commonest haematological problem encountered in pregnancy is iron-deficiency anaemia. Routine iron supplementation in all pregnant women is probably not justified in developed countries, but if iron deficiency is detected it is advisable to treat as early as possible. Normal pregnancy is associated with marked changes in all aspects of haemostasis, the overall effect of which is to generate a state of hypercoagulability. These changes in haemostasis, while reducing the risks of excessive blood loss at delivery, significantly increase the risk of venous thromboembolic disease in pregnancy.
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- Section 1 Patients and their treatment
- Section 2 Background to medicine
- Section 3 Cell biology
- Section 4 Immunological mechanisms
- Section 5 Principles of clinical oncology
- Section 6 Old age medicine
- Section 7 Pain and palliative care
- Section 8 Infectious diseases
- Section 9 Sexually transmitted diseases
- Section 10 Environmental medicine, occupational medicine, and poisoning
- Section 11 Nutrition
- Section 12 Metabolic disorders
- Section 13 Endocrine disorders
- Section 14 Medical disorders in pregnancy
- 14.1 Physiological changes of normal pregnancy
- 14.2 Nutrition in pregnancy
- 14.3 Medical management of normal pregnancy
- 14.4 Hypertension in pregnancy
- 14.5 Renal disease in pregnancy
- 14.6 Heart disease in pregnancy
- 14.7 Thrombosis in pregnancy
- 14.8 Chest diseases in pregnancy
- 14.9 Liver and gastrointestinal diseases of pregnancy
- 14.10 Diabetes in pregnancy
- 14.11 Endocrine disease in pregnancy
- 14.12 Neurological conditions in pregnancy
- 14.13 The skin in pregnancy
- 14.14 Autoimmune rheumatic disorders and vasculitis in pregnancy
- 14.15 Maternal infection in pregnancy
- 14.16 Fetal effects of maternal infection
- 14.17 Blood disorders in pregnancy
- 14.18 Malignant disease in pregnancy
- 14.19 Maternal critical care
- 14.20 Prescribing in pregnancy
- 14.21 Contraception for women with medical diseases
- Section 15 Gastroenterological disorders
- Section 16 Cardiovascular disorders
- Section 17 Critical care medicine
- Section 18 Respiratory disorders
- Section 19 Rheumatological disorders
- Section 20 Disorders of the skeleton
- Section 21 Disorders of the kidney and urinary tract
- Section 22 Haematological disorders
- Section 23 Disorders of the skin
- Section 24 Neurological disorders
- Section 25 Disorders of the eye
- Section 26 Psychiatric and drug-related disorders
- Section 27 Forensic medicine
- Section 28 Sport and exercise medicine
- Section 29 Biochemistry in medicine
- Section 30 Acute medicine