Can the Induction of Labor with Misoprostol Increase Maternal Blood Loss?

Abstract

Purpose To evaluate blood loss during misoprostol-induced vaginal births and during cesarean sections after attempted misoprostol induction.

Methods We conducted a prospective observational study in 101 pregnant women indicated for labor induction; pre- and postpartum hemoglobin levels were measured to estimate blood loss during delivery. Labor was induced by administering 25 µg vaginal misoprostol every 6 hours (with a maximum of 6 doses). The control group included 30 patients who spontaneously entered labor, and 30 patients who underwent elective cesarean section. Pre- and postpartum hemoglobin levels were evaluated using the analysis of variance for repeated measurements, showing the effects of time (pre- and postpartum) and of the group (with and without misoprostol administration).

Results There were significant differences between pre- and postpartum hemoglobin levels (p < 0.0001) with regard to misoprostol-induced vaginal deliveries (1.6 ± 1.4 mg/dL), non-induced vaginal deliveries (1.4 ± 1.0 mg/dL), cesarean sections after attempted misoprostol induction (1.5 ± 1.0 mg/dL), and elective cesarean deliveries (1.8 ± 1.1 mg/dL). However, the differences were proportional between the groups with and without misoprostol administration, for both cesarean (p = 0.6845) and vaginal deliveries (p = 0.2694).

Conclusions Labor induction using misoprostol did not affect blood loss during delivery.

Resumo

Objetivo Avaliar a perda sanguínea em partos vaginais induzidos com misoprostol, e em cesáreas com tentativa prévia de indução do parto com misoprostol.

Métodos Realizou-se estudo prospectivo observacional com 101 gestantes com indicação para indução do trabalho de parto, as quais foram avaliadas pela dosagem de hemoglobina pré e pós-parto para estimativa da perda sanguínea no parto. Procedeu-se à indução do trabalho de parto com misoprostol 25 µg, via vaginal, a cada 6 horas, em um número máximo de 6 doses. O grupo controle foi composto por 30 pacientes que entraram em trabalho de parto espontaneamente, e por 30 pacientes que se submeteram a cesárea eletiva. O estudo da hemoglobina, antes e depois do parto, foi avaliado por ANOVA para medidas repetidas, no qual foi verificado o efeito do tempo (pré e pós-parto) e o efeito do grupo (com e sem uso do misoprostol).

Resultados Existem diferenças significativas entre os níveis de hemoglobina pré e pós-parto (p < 0,0001) nos partos vaginais induzidos pelo misoprostol (1,6 ± 1,4 mg/dL), nos partos vaginais não induzidos (1,4 ± 1,0 mg/dL), nas cesáreas com tentativa prévia de indução (1,5 ± 1,0 mg/dL), e nas cesáreas eletivas (1,8 ± 1,1mg/dL). Porém, as diferenças foram proporcionais em ambos os grupos, ou seja, ocorreu diferença tanto no grupo que fez uso do misoprostol quanto no grupo que não fez uso do medicamento, tanto na cesárea (p = 0,6845) quanto no parto vaginal (p = 0,2694).

Conclusões A indução do parto com misoprostol não alterou a perda sanguínea durante o parto.

Keywords

induced labor - misoprostol - postpartum hemorrhage - hemoglobin - vaginal birth

Palavras-chave

trabalho de parto induzido - misoprostol - hemorragia pós-parto - hemoglobina - parto vaginal

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