Evaluation of postpartum blood loss after misoprostol-induced labour



The article by Elsedeek et al.1 is interesting and contains a logical explanation for postpartum haemorrhage (PPH) in women with induced short labours. It showed an increase in PPH in women induced with misoprostol compared with oxytocin. This questions the established view that misoprostol is the most effective drug for the management of PPH.

The two groups (Misoprostol and Oxytocin) were compared without analysing the blood loss by parity. It is not clear from the data if precipitate labour occurred more in second and subsequent labours than in first labours. Expressing parity as the authors did as a numerical average is unusual and may hide important information. It is more conventional to group by first labour compared with the second and subsequent labours.

Many woman want to remain active during labour and prefer to avoid an intravenous drip. Prolonged restriction of movement in labour because of intravenous infusions may increase the risk of thromboembolism. In a small randomised control study,2 comparing sublingual misoprostol versus vaginal Prostin (prostaglandin E2) from our hospital (Homerton university Hospital, London), a satisfaction questionnaire was given to patients. It was found that women were more satisfied in the misoprostol group (presumably because of the avoidance of vaginal examinations) and wanted to use it again in future and would recommend it to friends. Since then, many of our local women request sublingual misoprostol for induction of labour. It obviates the need for an intravenous drip and allows women to remain ambulant.

In the article by Elsedeek et al.,1 the study by Phillip et al.3 is mentioned as the only study looking at postpartum blood loss. In 2001, a Cochrane review (2001)4 found that for women with an unfavourable cervix, there was a relative risk of 1.61 (95% CI, 0.62–4.19) for the development of PPH in women receiving oxytocin alone versus those receiving vaginal prostin (prostaglandin E2) for cervical ripening.

Recently (2008), a randomised controlled trial of intravaginal dinoprostone (2 mg once every 6 hours), misoprostol (25 μg once every 4 hours) and transcervical balloon catheter for induction of labour did not show a statistically significant difference between the treatment groups with regard to postpartum bleeding. The mean Bishop’s score was 3.2, 3.1 and 3.4, respectively, in the treatment groups.5 This suggests that the dose of misoprostol used in the study by Elsedeek et al. was too high for women with a more favourable initial Bishop score [4.20 ± 1.37 (misoprostol), 4.37 ± 1.25 (oxytocin)]. This might be the reason for their observation of a higher rate of PPH in misoprostol induced labours. It would be interesting to further evaluate the incidence of PPH using lower doses of misoprostol in women with a favourable Bishop score, with analysis of blood loss by parity.