Severity of haemolytic disease of the fetus and newborn in patients with a history of intrauterine transfusions in a previous pregnancy: A nationwide retrospective cohort study.

OBJECTIVE

Pregnant women who received at least one intrauterine transfusion (IUT) for haemolytic disease of the fetus and newborn (HDFN) in the preceding pregnancy are presumed to have a high likelihood of requiring IUTs again, often starting at an earlier gestational age. Our aim was to quantify these risks in a large national cohort.

DESIGN

Retrospective cohort study of a nationwide Dutch database.

SETTING

The Netherlands.

POPULATION

All women treated in The Netherlands with IUTs for Rhesus D (RhD)- or Kell-mediated HDFN between 1999 and 2017 and their follow-up pregnancies were included. Pregnancies with an antigen-negative fetus were excluded.

METHODS

Electronic patient files were searched for the number and gestational age of each IUT, and analysed using descriptive statistics and linear regression.

MAIN OUTCOME MEASURES

Percentage of women requiring one or more IUTs again in the subsequent pregnancy, and gestational age at first IUT in both pregnancies.

RESULTS

Of the 321 women in our study population, 21% (69) had a subsequent ongoing pregnancy at risk. IUTs were administered in 86% (59/69) of cases. In subsequent pregnancies, the median gestational age at first IUT was 3 weeks earlier (interquartile range -6.8 to 0.4) than in the preceding pregnancy.

CONCLUSIONS

Our study shows that pregnant women with a history of IUTs in the previous pregnancy are highly likely to require IUTs again, and on average 3 weeks earlier. Clinicians need to be aware of these risks and ensure timely referral, and close surveillance from early pregnancy onwards. Additionally, for women with a history of IUT and their caregivers, this information is essential to enable adequate preconception counselling.