Prophylaxis and Treatment of Anaemia during Pregnancy

Iron supplementation in pregnancy. General practitioners' compliance with official recommendations

OBJECTIVE--To compare general practitioners' routines regarding iron supplementation in pregnancy with national recommendations.

DESIGN

Mailed questionnaire to general practitioners.

SETTING

A county in western Norway.

SUBJECTS

184 general practitioners.

MAIN OUTCOME MEASURES

Descriptive registration of reported routines regarding assessment and supplementation of iron.

RESULTS

11% of general practitioners reported complete adherence to the national programme recommending iron supplements for everyone in the second half of pregnancy and use of s-ferritin estimation if Hb falls below 11 g/dl. 36% of the doctors prescribed iron supplements routinely irrespective of iron status. 87% reported use of s-ferritin estimation in antenatal care; usually on indication of low Hb, almost 20% as a routine screening in all pregnancies.

CONCLUSION

General practitioners' compliance with national recommendations for iron supplementation in pregnancy is very low and probably reveals a need both for a review of the national recommendations and for an approach to increase compliance with given standards.

The effect of maternal anaemia and iron deficiency on the ratio of fetal weight to placental weight

OBJECTIVE

To examine the maternal influences which determine large placental weight and a high ratio of placental weight to birthweight. These are known predictors of adult blood pressure.

DESIGN

Retrospective analysis of routine obstetric and haematology department records for a large cohort of pregnant women.

SETTING

John Radcliffe Hospital, Oxford.

SUBJECTS

8684 pregnant women who were delivered between January 1987 and January 1989 and whose records could be linked to the results of two or more pregnancy blood counts.

MAIN OUTCOME MEASURES

Placental weight and the ratio of placental weight to birthweight.

RESULTS

Large placental weight was associated with a low maternal haemoglobin and a fall in maternal mean cell volume during pregnancy. The highest ratio of placental weight to birthweight occurred in the most anaemic women with the largest falls in mean cell volume. Large placental weight and a high ratio of placental weight to birthweight were also independently associated with a high maternal body mass index. Maternal smoking reduced placental weight, but increased the ratio of placental weight to birthweight.

CONCLUSIONS

Anaemia and iron deficiency during pregnancy are associated with large placental weight and a high ratio of placental weight to birthweight. This points to maternal nutritional deficiency as a cause for discordance between placental and fetal growth. This may have important implications for the prevention of adult hypertension, which appears to have its origin in fetal life.

A randomized comparison of routine versus selective iron supplementation during pregnancy

This trial compares routine and selective iron supplementation during pregnancy to determine whether routine supplementation adversely affects fetal growth, increases infections and subjective adverse effects, and/or delays birth. At their first prenatal visit, 2912 pregnant women were randomized into two groups (2694 gave birth). Compliance was satisfactory as measured by self-reports by mothers and hematocrit values in the third trimester. More women in the routinely supplemented group had subjected adverse effects. The groups were similar in regard to most of the other outcomes. In the selectively supplemented group, there was weak evidence for increase in sick-days, referrals to hospital outpatient clinic, cesarean section, blood transfusions, and infants who were diagnosed as having hyperviscosity. In the routine group, there were somewhat more women with gestations greater than or equal to 41 weeks and more dead infants. The subgroup analyses suggest that some of the apparently worse outcomes in the selective group were due to reactions of midwives and physicians to low hematocrit values.

Iron supplementation during pregnancy--experiences of a randomized trial relying on health service personnel

This article reports the design and feasibility of a randomized controlled trial of the benefits of routine iron prophylaxis during pregnancy. The multicenter trial, supported by a small budget, relied on health service personnel in Finnish maternity centers. Iron prophylaxis has had an established position in Finnish maternity care, and iron is freely available. This contributed to our decision to ask for informed consent after randomization. During a year, 2960 mothers were recruited by midwives in 27 maternity health centers and randomized into two groups: selective and routine iron supplementation. Mothers were followed until the postpartum checkup, and data were collected by five different questionnaires and abstracted from the infant's patient record. Adherence of the midwives to the study protocol was satisfactory, as was mothers' compliance with recommended treatments. However, because the study was designed to compare two treatment policies, problems of nonmasking hamper of the biologic effects of iron. This trial encourages the use of existing health services and their personnel in evaluation of medical technology.

Iron requirement in normal pregnancy as assessed by serum ferritin, serum transferrin saturation and erythrocyte protoporphyrin determinations

Serum iron, serum iron-binding capacity, serum ferritin and erythrocyte protoporphyrin were determined during uncomplicated pregnancy in 45 healthy women; 22 were given oral iron while the others were given a placebo. When iron was not given, 15 out of 23 women had exhausted iron stores and iron deficiency at term, as judged from low serum ferritin, low serum transferrin saturation and high erythrocyte protoporphyrin values. Only seven of them had a haemoglobin concentration between 10 and 11 g/dl at term but none had values less than 10 g/dl. In the iron-treated group (n = 22) none of the women developed iron deficiency. Serum ferritin was the most sensitive and specific test of iron deficiency. A practical procedure to detect iron deficiency and to control iron supplementation in pregnancy is suggested.