Results
Out of 101 women with singleton
pregnancies giving birth prior to 34 completed weeks of gestation due to
preeclampsia with severe features during the study period, the aPL
antibodies status of 55 women was available for analysis. The median
gestational age at diagnosis was 31 (IQR 28-33), and the median
gestational age at delivery was 32 (IQR (29-34) with a mean birth weight
of 1458±568 grams. The study group – aPL-positive group – comprised of
20 women, while the aPL-negative group comprised of 35 women who served
as controls. The antibodies distribution of the aPL-positive group is
presented in Table 1.
Table 2 displays the demographic and clinical characteristics of the
study and control groups. All participants were Caucasian. Women in the
study group were younger than controls (30.15±4.64 vs. 34.34±7.02,
p=0.01), but with higher gravidity (3, IQR 1.25-4.75, in the study group
vs. 2, IQR 1-2, in controls, p=0.01). Medical history of chronic
hypertension and diabetic mellitus, pre-gestational or gestational, were
comparable between the two groups. There were 2 cases of systemic lupus
erythematosus among study group cases and one among controls.
Additionally, there was one case of glomerulonephritis and one case of
Behҫet’s disease among the study group.
The obstetric outcomes and pregnancy complications for pregnancies in
aPL-positive and aPL-negative women are presented in Table 3. Median
gestational age at hospitalization was three weeks earlier in
aPL-positive women compared with aPL-negative women
(29, IQR 26.28–32, vs. 32, IQR
28-33 weeks gestation, respectively, p=0.05). aPL-positive women
delivered at significantly earlier gestational age
(30, IQR 28.3-32.8 weeks, vs. 33,
IQR 30-34 weeks, p=0.02) with lower mean neonatal birth weight compared
with those with negative aPL antibodies (1266.7±579.6 grams vs.
1567.3±539.7 grams, respectively, p=0.058). There were two peripartum
fetal deaths in our cohort, both to aPL-positive mothers. One case was
an antepartum fetal death at 27 weeks gestation of a severely
growth-restricted fetus, and the other case was a severely
growth-restricted neonate born at 24 weeks gestation who died at two
days of age from complications of prematurity. The rate of cesarean
section was high and comparable between the groups. Furthermore, women
in the aPL-positive group were hospitalized for a longer period after
delivery compared with aPL-negative group women (9, IQR 6-12, vs. 7, IQR
6-9 days, respectively, p=0.03).
In order to assess the severity of the disease, we evaluated clinical
and laboratory characteristics of preeclampsia with severe features in
both groups. Although maximal systolic blood pressure was lower for
aPL-positive women compared with aPL-negative controls (149.72±22.6, vs.
170.03±23.1, p=0.004), overall disease severity was more significant for
aPL-positive women. Platelet nadir was significantly lower for
aPL-positive compared with aPL-negative women
(mean
97.2±49.7103/µL vs. 141.3±61.13/µL,
respectively, p<0.001) and maximal serum creatinine was higher
(1.02±0.32 mg/dL vs. 0.92±0.13
mg/dL, p=0.03). Moreover, both cases of eclampsia occurred in the
aPL-positive women. Table 3 outlines the frequency of severe pregnancy
complications in both groups.
Twenty neonates were born to aPL-positive mothers, and 35 to
aPL-negative mothers (Table 4). Rates of complications of prematurity
were comparable between groups, except for higher rates of retinopathy
of prematurity in women with positive aPL antibodies
(30.0% vs. 5.7%, p=0.02).
As mentioned above, there were two antepartum fetal deaths in our
cohort, both to study group mothers. Neonatal death before discharge
occurred in one neonate born to an aPL-positive mother and one of 35
neonates born to aPL-negative mothers. Therefore, overall perinatal
mortality was higher for aPL-positive women compared with aPL-negative
women, although not statistically significant (3 out of 20 (15%) vs. 1
out of 35 (2.8%), p=0.13).