Main findings
There are four main findings from the large FMF prospective study in
women with singleton pregnancies living in England. First, multiple
logistic regression analysis demonstrated that in addition to black
racial origin, increased risk for PE is provided by increasing maternal
age and weight, conception by IVF, history of chronic hypertension and
diabetes type 1, family history of PE and previous pregnancy affected by
PE; the risk for PE decreases with increasing height, cigarette smoking,
and previous birth of small for gestational age neonate. Second, in
black women, compared to white women, after adjustment for elements of
maternal characteristics and medical history there is a 2-fold, 2.5-fold
and 3-fold higher risk of total PE, preterm PE and early PE,
respectively, and a 25% increase in the risk of GH. Third, in women of
South Asian racial origin, compared to white women, there is a 1.5-fold
higher risk of preterm and early PE but no significant difference in
total PE or GH. Fourth, in women of East Asian racial origin, compared
to white women, there is no significant difference in the risk of PE or
GH.
The literature search identified only 19 studies that provided data on
the incidence of PE in some of the racial groups as defined by the FMF
study. In the assessment of the quality of the included studies only two
were considered to be at low risk of bias. In the meta-analyses of data
from previous studies combined with those of the FMF study the
unadjusted risk of PE in black women, compared to white women was higher
and in women of East Asian origin, compared to white women, the risk was
lower; in women of South Asian racial origin, compared to white women,
the risk was not significantly different. However, in the meta-analysis
of three previous studies that provided adjusted ORs, albeit with
adjustment for very few relevant maternal characteristics, combined with
our data the risk of PE in women of black and South Asian racial origin,
compared to white women, was increased, whereas in East Asian women the
risk of PE was not significantly different from that in white women.