The association between haemoglobin levels in the first 20 weeks of pregnancy and pregnancy outcomes

Autoři: Deborah A. Randall aff001;  Jillian A. Patterson aff001;  Felicity Gallimore aff001;  Jonathan M. Morris aff001;  Therese M. McGee aff003;  Jane B. Ford aff001
Působiště autorů: The University of Sydney Northern Clinical School, Women and Babies Research, St Leonards, New South Wales, Australia aff001;  Northern Sydney Local Health District, Kolling Institute, New South Wales, Australia aff002;  Women’s and Newborn Health, Westmead Hospital, Westmead NSW, Australia aff003;  The University of Sydney, Sydney NSW, Australia aff004
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0225123



Low haemoglobin has been linked to adverse pregnancy outcomes. Our study aimed to assess the association of haemoglobin (Hb) in the first 20 weeks of pregnancy, and restoration of low Hb levels, with pregnancy outcomes in Australia.


Clinical data for singleton pregnancies from two tertiary public hospitals in New South Wales were extracted for 2011–2015. The relationship between the lowest Hb result in the first 20 weeks of pregnancy and adverse outcomes was determined using adjusted Poisson regression. Those with Hb <110 g/L were classified into ‘restored’ and ‘not restored’ based on Hb results from 21 weeks onwards, and risk of adverse outcomes explored with adjusted Poisson regression.


Of 31,906 singleton pregnancies, 4.0% had Hb <110 and 10.2% had ≥140 g/L at ≤20 weeks. Women with low Hb had significantly higher risks of postpartum haemorrhage, transfusion, preterm birth, very low birthweight, and having a baby transferred to higher care or stillbirth. High Hb was also associated with higher risks of preterm, very low birthweight, and transfer to higher care/stillbirth. Transfusion was the only outcome where risk decreased with increasing Hb. Risk of transfusion was significantly lower in the ‘restored’ group compared with the ‘not restored’ group (OR 0.39, 95% CI 0.22–0.70), but restoration of Hb did not significantly affect the other outcomes measured.


Women with both low and high Hb in the first 20 weeks of pregnancy had higher risks of adverse outcomes than those with normal Hb. Restoring Hb after 20 weeks did not improve most adverse outcome rates but did reduce risk of transfusion.

Klíčová slova:

anémia – Birth – Blood transfusion – Hypertensive disorders in pregnancy – Postpartum hemorrhage – Pregnancy – Preterm birth – Stillbirths


1. Patterson J, Roberts C, Bowen J, Irving D, Isbister J, Morris J, et al. Obstetric blood transfusion during pregnancy, birth and the postnatal period: a population based study. Obstet Gynecol. 2014;123(1):126–33. doi: 10.1097/AOG.0000000000000054 24463672

2. Knight M, Callaghan WM, Berg C, Alexander S, Bouvier-Colle MH, Ford JB, et al. Trends in postpartum hemorrhage in high resource countries: a review and recommendations from the International Postpartum Hemorrhage Collaborative Group. BMC Pregnancy Childbirth. 2009;9:55. doi: 10.1186/1471-2393-9-55 19943928

3. Ford JB, Roberts CL, Simpson JM, Vaughan J, Cameron CA. Increased postpartum hemorrhage rates in Australia. Int J Gynaecol Obstet. 2007;98(3):237–43. doi: 10.1016/j.ijgo.2007.03.011 17482190

4. Muñoz M, Peña-Rosas JP, Robinson S, Milman N, Holzgreve W, Breymann C, et al. Patient blood management in obstetrics: Management of anaemia and haematinic deficiencies in pregnancy and in the post-partum period: NATA consensus statement. Transfus Med. 2018;28(1):22–39. doi: 10.1111/tme.12443 28722245

5. Milman N. Iron and pregnancy—A delicate balance. Annals of Hematology. 2006;85(9):559–65. doi: 10.1007/s00277-006-0108-2 16691399

6. Milman N. Prepartum anaemia: prevention and treatment. Annals of Hematology. 2008;87(12):949–59. doi: 10.1007/s00277-008-0518-4 18641987

7. National Blood Authority. Patient Blood Management Guideline: Module 5 –Obstetrics and Maternity. Canberra: National Blood Authority, 2015.

8. World Health Organization. Haemoglobin concentrations for the diagnosis of anaemia and assessment of severity. Geneva: WHO, 2011 Document No.: WHO/NMH/NHD/MNM/11.1.

9. Centers for Disease Control and Prevention. Recommendations to prevent and control iron deficiency in the United States. Atlanta, GA: CDC; 1998 [cited 2019 Jan 15]. Available from:

10. Drukker L, Hants Y, Farkash R, Ruchlemer R, Samueloff A, Grisaru-Granovsky S. Iron deficiency anemia at admission for labor and delivery is associated with an increased risk for Cesarean section and adverse maternal and neonatal outcomes. Transfusion. 2015;55(12):2799–806. doi: 10.1111/trf.13252 26246160

11. Allen LH. Anemia and iron deficiency: effects on pregnancy outcome. Am J Clin Nutr. 2000;71(5):1280–4.

12. Haider BA, Olofin I, Wang M, Spiegelman D, Ezzati M, Fawzi WW. Anaemia, prenatal iron use, and risk of adverse pregnancy outcomes: systematic review and meta-analysis. BMJ. 2013;346:f3443. doi: 10.1136/bmj.f3443 23794316

13. Murphy JF, Newcombe RG, O'Riordan J, Coles EC, Pearson JF. Relation of haemoglobin levels in first and second trimesters to outcome of pregnancy. Lancet. 1986;327(8488):992–5.

14. Department of Health. Clinical Practice Guidelines: Pregnancy Care. Canberra, Australia: Australian Government Department of Health, 2018.

15. Royal Australian and New Zealand College of Obstetricians and Gynaecologists. Statement C-Obs 25: Vitamin and Mineral Supplementation and Pregnancy. Melbourne: RANZCOG, 2014 Document No.: C-Obs 25.

16. Isbister JP. The three-pillar matrix of patient blood management—An overview. Best Pract Res Clin Anaesthesiol. 2013;27(1):69–84. doi: 10.1016/j.bpa.2013.02.002 23590917

17. National Centre for Classification in Health. The International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification (ICD-10-AM), Australian Classification of Health Interventions (ACHI) and Australian Coding Standards (ACS), Seventh Edition. Sydney: National Centre for Classification in Health, 2010.

18. SNOMED International. What is SNOMED CT? 2018 [cited 2018 Aug 21]. Available from:

19. Austin PC. Balance diagnostics for comparing the distribution of baseline covariates between treatment groups in propensity-score matched samples. Statistics in Medicine. 2009;28(25):3083–107. doi: 10.1002/sim.3697 19757444

20. Dobbins TA, Sullivan EA, Roberts CL, Simpson JM. Australian national birthweight percentiles by sex and gestational age, 1998–2007. Med J Aust. 2012;197(5):291–4. doi: 10.5694/mja11.11331 22938128

21. Australian Bureau of Statistics. 2033.0.55.001—Census of Population and Housing: Socio-Economic Indexes for Areas (SEIFA), Australia, 2011 2011 [cited 2018 Jun 15]. Available from:

22. Gonzales GF, Steenland K, Tapia V. Maternal hemoglobin level and fetal outcome at low and high altitudes. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology. 2009;297(5):R1477–R85. doi: 10.1152/ajpregu.00275.2009 19741055

23. Peña‐Rosas JP, De‐Regil LM, Garcia‐Casal MN, Dowswell T. Daily oral iron supplementation during pregnancy. Cochrane Database Syst Rev. 2015;(7).

24. Owiredu WKBA, Osakunor DNM, Turpin CA, Owusu-Afriyie O. Laboratory prediction of primary postpartum haemorrhage: A comparative cohort study. BMC Pregnancy Childbirth. 2016;16(1).

25. Kavle JA, Stoltzfus RJ, Witter F, Tielsch JM, Khalfan SS, Caulfield LE. Association between anaemia during pregnancy and blood loss at and after delivery among women with vaginal births in Pemba Island, Zanzibar, Tanzania. J Health Popul Nutr. 2008;26(2):232–40. 18686556

26. Dewey KG, Oaks BM. U-shaped curve for risk associated with maternal hemoglobin, iron status, or iron supplementation. Am J Clin Nutr. 2017;106:1694S–702S. doi: 10.3945/ajcn.117.156075 29070565

27. Gonzales GF, Tapia V, Fort AL. Maternal and Perinatal Outcomes in Second Hemoglobin Measurement in Nonanemic Women at First Booking: Effect of Altitude of Residence in Peru. ISRN Obstetrics and Gynecology. 2012;2012:7.

28. Sinha P, Kuruba N. Ante-partum haemorrhage: An update. J Obstet Gynaecol. 2008;28(4):377–81. doi: 10.1080/01443610802091487 18604667

29. Vahanian SA, Lavery JA, Ananth CV, Vintzileos A. Placental implantation abnormalities and risk of preterm delivery: A systematic review and metaanalysis. Am J Obstet Gynecol. 2015;213(4):S78–S90.

30. Scheil W, Jolly K, Scott J, Catcheside B, Sage L, Kennare R. Pregnancy Outcome in South Australia 2015. Adelaide: Pregnancy Outcome Unit, SA Health, Government of South Australia, 2017.

31. Stevens GA, Finucane MM, De-Regil LM, Paciorek CJ, Flaxman SR, Branca F, et al. Global, regional, and national trends in haemoglobin concentration and prevalence of total and severe anaemia in children and pregnant and non-pregnant women for 1995–2011: A systematic analysis of population-representative data. Lancet Global Health. 2013;1(1):E16–E25. doi: 10.1016/S2214-109X(13)70001-9 25103581

32. Chatterjee R, Shand A, Nassar N, Walls M, Khambalia AZ. Iron supplement use in pregnancy—Are the right women taking the right amount? Clin Nutr. 2016;35(3):741–7. doi: 10.1016/j.clnu.2015.05.014 26070630

Článek vyšel v časopise


2019 Číslo 11