Administration of low-dose aspirin to mothers with small for gestational age fetuses and abnormal umbilical Doppler studies to increase birthweight: a randomised double-blind controlled trial.
OBJECTIVE
To determine whether antenatal treatment (for > or = 14 days) with 100 mg aspirin daily, given to mothers with small for gestational age fetuses and abnormal umbilical Doppler, will increase birthweight.


METHODS
Randomised, double-blind placebo controlled trial.


METHODS
A tertiary referral centre.


METHODS
Ninety-nine women, of whom 65 were treated for > or = 14 days (32 with aspirin and 33 with placebo) and comprised the study group. The entry criteria were: singleton pregnancy with ultrasound evidence of a small for gestational age fetus (abdominal circumference < 10%); previous anatomy scan < 20 weeks and no evidence of fetal abnormality; gestation between 24 and 36 weeks; umbilical artery Doppler resistance index > 95% for gestation; no previous aspirin treatment in pregnancy; and no contra-indication to aspirin treatment.


RESULTS
The mean duration of treatment was 30 days for aspirin treated, and 29 for placebo. No difference was found in birthweight or other measures of fetal growth or newborn morbidity between those treated with aspirin or placebo. Compliance, assessed by thromboxane B2 analysis, showed almost complete suppression of thromboxane B2 in aspirin treated women.


CONCLUSIONS
Low-dose aspirin did not increase birthweight in pregnancies where the fetus has abnormal umbilical Doppler and is thought to be small for gestational age.
McCowan
L M
LM
Department of Obstetrics and Gynaecology, University of Auckland, New Zealand.
Harding
J
J
Roberts
A
A
Barker
S
S
Ford
C
C
Stewart
A
A
D000328:Adult; D001241:Aspirin / Q000008:administration & dosage*; D001724:Birth Weight / Q000187:drug effects*; D004311:Double-Blind Method; D005260:Female; D005317:Fetal Growth Retardation / Q000188:drug therapy*; D006801:Humans; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D011247:Pregnancy; D013929:Thromboxane B2 / Q000032:analysis; D018608:Ultrasonography, Doppler; D014470:Umbilical Cord / Q000098:blood supply* / Q000000981:diagnostic imaging
D010975:Platelet Aggregation Inhibitors; D013929:Thromboxane B2; D001241:Aspirin