Protein Z in patients with pregnancy complications.
OBJECTIVE
This study was undertaken to evaluate the association between protein Z concentration and pregnancy complications.


METHODS
A prospective case-control study was conducted over a 2-year period to evaluate the prevalence of protein Z deficiency in pregnancy complications. Protein Z levels were measured at the time of diagnosis of complications such as preeclampsia, intrauterine growth restriction, and intrauterine fetal demise. Protein Z deficiency was defined as a plasma level below 1.2 mg/L. In addition to patients presenting with pregnancy complications, healthy age-matched nonpregnant and pregnant women were invited to participate.


RESULTS
A total of 145 women were included in the study: 50 nonpregnant women, 34 healthy pregnant women, 29 women with preeclampsia, 25 women presented with intrauterine growth restriction, and 7 women with intrauterine fetal demise. The median protein Z level was similar in healthy pregnant and nonpregnant women (1.63 [0.47-3.1] mg/L and 1.69 [0.7-3] mg/L, respectively). Three women with normal pregnancies had a low protein Z level (8.8%), compared with 8 patients presenting with intrauterine growth restriction (33.3%) and 8 patients with intrauterine fetal demise (50%). Compared with normal pregnancy, the frequency of decreased protein Z was significantly higher in cases of intrauterine growth restriction and in intrauterine fetal demise (relative risk [RR] 1.96, 95% CI 1.16-3.32; P = .041 and RR 3.36, 95% CI 1.65-6.8; P = .0031, respectively), but not in preeclampsia (RR 1.6, 95% CI 0.9-2.8; P = .23). Placenta histologic examination revealed vascular lesions in 50% of patients with protein Z deficiency and in 33% of patients with normal levels of protein Z (RR 0.84; 95% CI 0.6-1.2).


CONCLUSIONS
Protein Z deficiency is associated with late fetal demise and intrauterine growth restriction. The pathophysiologic role of protein Z deficiency, either congenital or caused by the presence of specific antibodies remains unclear and should be further investigated.
Bretelle
Florence
F
Service de Gynécologie-Obstétrique, Pr. B. Blanc, Centre Hospitalo-Universitaire de la Conception, 13385 Marseille Cedex, France. florence.bretelle@mail.ap-hm.fr
Arnoux
Dominique
D
Shojai
Raha
R
D'Ercole
Claude
C
Sampol
José
J
Dignat
Françoise
F
Camoin-Jau
Laurence
L
D000328:Adult; D001798:Blood Proteins / Q000172:deficiency*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology*; D015995:Prevalence; D011446:Prospective Studies; D011488:Protein Deficiency / Q000150:complications / Q000453:epidemiology*
D001798:Blood Proteins; C026080:plasma protein Z