[Transvaginal bleeding in pregnancy, as risk factor of Rhesus-D antigen isoimmunization].

Abstract

OBJECTIVE:

The aim of the present study was to evaluate transvaginal bleeding (TVB) as a risk factor for Rhesus isoimmunization during pregnancy, in order to optimize the application of Anti-D gammaglobulin in non-immunized pregnant women, as an alternative to the routine application of Anti-D at 28 weeks of gestation.

MATERIAL AND METHODS:

This case-control study was conducted from 1995 to 2001 at Mexico's National Perinatology Institute. Cases (n = 24) were non-immunized pregnant women who showed positive anti-D antibody seroconversion during pregnancy or during the early puerperium. Controls (n = 24) were non-immunized pregnant women who enrolled after each case, with similar clinical characteristics but who had no anti-D antibody seroconversion during pregnancy. In all cases the newborns were Rh-positive. None of the patients received immunoprophylaxis at 28 weeks of gestation. The presence of TVB was recorded at any stage of pregnancy and before labor. Odds ratios with 95% confidence intervals were used to assess associations.

RESULTS:

TVB was observed in 18/24 (75%) cases and in 5/24 (20%) controls. Preterm uterine contractions and threatened miscarriage were the most frequent causes of TVB. The presence of one TVB event during pregnancy increased 11.4 times (95% CI 2.9-44.0) the likelihood of Rhesus isoimmunization. TVB after 20 weeks of gestation increased the likelihood 5.0 times (95% CI 1.3-19.1). TVB before 20 weeks of gestation was not significantly associated with Rh isoimmunization (OR = 7.6, 95% CI 0.8-69.5).

CONCLUSIONS:

Prophylaxis with anti-D gammaglobulin should be given to all non-immunized Rhesus-negative pregnant woman with TVB at any stage of pregnancy. The English version of this paper is available at:http://www.insp.mx/salud/index.html.

• Authors: Edgar Hernández-Andrade, José Roberto Ahued-Ahued
• Journal: Salud publica de Mexico (Salud Publica Mex) 2003 Nov-Dec Vol. 45 Issue 6 Pg. 492-6 ISSN: 0036-3634 [Print] Mexico
• Vernacular Title: Sangrado transvaginal durante el embarazo, como factor de riesgo para isoinmunización al antígeno Rhesus-D.
• PMID: 14974293 (Publication Type: English Abstract, Journal Article)

Chemical References

• Rh-Hr Blood-Group System
• Rho(D) antigen

Topics

• Adult
• Case-Control Studies
• Female
• Humans
• Pregnancy
• Retrospective Studies
• Rh Isoimmunization (immunology, prevention & control)
• Rh-Hr Blood-Group System
• Risk Factors
• Uterine Hemorrhage (epidemiology, etiology)