Reference values for α₁‐acid glycoprotein, α₁‐antitrypsin, albumin, haptoglobin, C‐reactive protein, IgA, IgG and IgM during pregnancy

Abstract

The objective of this study was to establish reference intervals and decision limits for the interpretation of the acute phase proteins alpha(1)-acid glycoprotein (orosomucoid), alpha(1)-antitrypsin, C-reactive protein (CRP), haptoglobin and albumin, IgA, IgG and IgM during pregnancy by longitudinal sampling from 52 healthy women with normal pregnancies. Each woman was sampled in weeks 7-17; weeks 17-24; weeks 24-28; weeks 28-31; weeks 31-34; weeks 34-38 and predelivery (-14-0 days prior to delivery) and postpartum (>6 weeks after delivery). The 2.5th and 97.5th percentiles were calculated according to the recommendations of the International Federation of Clinical Chemistry on the statistical treatment of reference values. Reference values for alpha(1)-acid glycoprotein, alpha(1)-antitrypsin, albumin, haptoglobin, CRP, IgA, IgG and IgM are reported. Most of these proteins changed during normal pregnancy, as a reflection of the major physiological and biochemical changes that occur in pregnancy. A laboratory test result from a pregnant woman should be compared with pregnancy-specific reference intervals.

Determinants of C-reactive protein concentrations in pregnant women with type 1 diabetes

“…In the present study, we showed that CRP levels significantly increased between the first trimester and mid-pregnancy, before stabilizing. Our results are consistent with those reported by Larsson et al, 19 who showed an increase in CRP levels until weeks 24 to 28 of uncomplicated pregnancy and a relative stabilization after this period. We initially hypothesized that maternal diabetes status may have some influence on CRP levels, as this was previously described in nonpregnant populations (both women and men).…”

The aetiology of anaemia during pregnancy: a study to evaluate the contribution of iron deficiency and common infections in pregnant Ugandan women

“…A high prevalence of infection and/or inflammation, indicated by elevated CRP, was also reported among 150 anaemic pregnant women in Malawi as mean CRP concentration was 30 mg/l and 35 % had elevated CRP (CRP >190 nmol/l (19·5 mg/l)) (7) . Although CRP increases during normal pregnancy (55,56) , these findings in pregnant women in Africa indicate higher concentrations than in other populations. Furthermore, a study in the USA reported that while median CRP was 4·8 mg/l during pregnancy, black race was independently associated with serum CRP levels greater than the 75th percentile (15·7 mg/l) (57) .…”

Expanding the Clinical Indications for α1-Antitrypsin Therapy

“…Hepatocytes are also responsible for IL-1/IL-6-inducible AAT production during inflammation. Levels of AAT also increase in the circulation during normal pregnancy (17) and in the process of aging (18). The half-life of AAT in the circulation is 3-5 d (16).…”

“…AAT rises during normal pregnancy (17). An intriguing association appears to exist between AAT inactivity and preterm premature rupture of membranes.…”