Kim Hinshaw

Management of out-of-hospital cardiac arrest (OHCA) in a pregnant patient is challenging, both logistically and emotionally. This review explores the adaptations to resuscitation in pregnancy; the indications and preparation for prehospital resuscitative hysterotomy (RH); the surgical procedure; and the post-procedure care. Prehospital clinicians should train for RH in their teams to maximise the chances of maternal and fetal survival. Further research is needed to understand the incidence of maternal OHCA, how we can improve the chain of survival and the duration of maternal cardiac arrest before RH becomes futile to inform future guidelines.

Background: Delay in the first stage of labour occurs in approximately 20% of nulliparous women. Recommended treatment is intravenous oxytocin, which shortens labour but does not affect the mode of birth. There is some evidence that a higher dose regimen may decrease the need for caesarean section. Objective: The primary objective was to establish if a high-dose regimen of oxytocin compared to the current standard-dose regimen reduced the need for caesarean section for nulliparous women with confirmed delay in the first stage of labour. Design: Multicentre, randomised double-blind controlled trial. Setting: Twenty-one maternity units in the United Kingdom. Participants: Consenting nulliparous women who had a singleton cephalic pregnancy, gestation of 37–41 weeks inclusive, confirmed delay in labour in first stage, ruptured membranes and for whom the clinical decision has been made to prescribe oxytocin. Interventions: Standard-dose regimen of oxytocin (2 mU/min increasing every 30 minutes to a maximum of 32 mU/min) compared with high-dose regimen (4 mU/min increasing every 30 minutes to a maximum of 64 mU/min). Main outcome measures: The primary outcome was the rate of caesarean section. Secondary outcomes included maternal and neonatal birth outcomes and safety. Results: One hundred and eighteen women were successfully randomised via third-party minimisation from an intended sample size of 1500 between 30 June 2017 and 14 November 2022. The caesarean section rate in the standard-dose group was 34% (20/58) and 27% (16/60) in the high-dose group. The intervention was provided as intended in 96% (113/118) of participants. There was no obvious suggestion that the high-dose regime was unsafe (all neonates were discharged home with mother), but this size of sample prohibited any definitive conclusions. Limitations: The trial did not meet its intended sample size due to a number of challenges. It was difficult for busy clinical staff to recruit women in labour in this acute, but not emergency, situation. The legislative requirements of undertaking research using interventional medicinal products imposed further constraints, and we encountered challenges in the production, blinding and monitoring required. Changes in clinical practice since trial design and commencement 10 years ago have resulted in fewer women going into spontaneous labour (reduced from 66% to 47%), and therefore potentially becoming eligible, due to more women having labour induced (22%–33%) or elective caesarean sections (12%–20%). These challenges were further compounded by a falling birth rate and the impact of the COVID-19 pandemic. Conclusions: The question of the optimum dose of oxytocin for nulliparous women delayed in the first stage of spontaneous labour remains an important unanswered clinical question, and the major challenge is how best to address this within the current regulatory framework. Future work: Future studies should consider whether the option of delayed consent would be suitable in this acute, but not emergency, situation. Funding: This synopsis presents independent research funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme as award number 14/140/44.

Trial design: A randomised, parallel-group, double-blind, placebo-controlled multicentre study with health economic and nested qualitative studies to determine if mifepristone (Mifegyne^®, Exelgyn, Paris, France) plus misoprostol is superior to misoprostol alone for the resolution of missed miscarriage. Methods: Women diagnosed with missed miscarriage in the first 14 weeks of pregnancy were randomly assigned (1 : 1 ratio) to receive 200 mg of oral mifepristone or matched placebo, followed by 800 μg of misoprostol 2 days later. A web-based randomisation system allocated the women to the two groups, with minimisation for age, body mass index, parity, gestational age, amount of bleeding and randomising centre. The primary outcome was failure to pass the gestational sac within 7 days after randomisation. The prespecified key secondary outcome was requirement for surgery to resolve the miscarriage. A within-trial cost-effectiveness study and a nested qualitative study were also conducted. Women who completed the trial protocol were purposively approached to take part in an interview to explore their satisfaction with and the acceptability of medical management of missed miscarriage. Results: A total of 711 women, from 28 hospitals in the UK, were randomised to receive either mifepristone plus misoprostol (357 women) or placebo plus misoprostol (354 women). The follow-up rate for the primary outcome was 98% (696 out of 711 women). The risk of failure to pass the gestational sac within 7 days was 17% (59 out of 348 women) in the mifepristone plus misoprostol group, compared with 24% (82 out of 348 women) in the placebo plus misoprostol group (risk ratio 0.73, 95% confidence interval 0.54 to 0.98; p = 0.04). Surgical intervention to resolve the miscarriage was needed in 17% (62 out of 355 women) in the mifepristone plus misoprostol group, compared with 25% (87 out of 353 women) in the placebo plus misoprostol group (risk ratio 0.70, 95% confidence interval 0.52 to 0.94; p = 0.02). There was no evidence of a difference in the incidence of adverse events between the two groups. A total of 42 women, 19 in the mifepristone plus misoprostol group and 23 in the placebo plus misoprostol group, took part in an interview. Women appeared to have a preference for active management of their miscarriage. Overall, when women experienced care that supported their psychological well-being throughout the care pathway, and information was delivered in a skilled and sensitive manner such that women felt informed and in control, they were more likely to express satisfaction with medical management. The use of mifepristone and misoprostol showed an absolute effect difference of 6.6% (95% confidence interval 0.7% to 12.5%). The average cost per woman was lower in the mifepristone plus misoprostol group, with a cost saving of £182 (95% confidence interval £26 to £338). Therefore, the use of mifepristone and misoprostol for the medical management of a missed miscarriage dominated the use of misoprostol alone. Limitations: The results from this trial are not generalisable to women diagnosed with incomplete miscarriage and the study does not allow for a comparison with expectant or surgical management of miscarriage. Future work: Future work should use existing data to assess and rank the relative clinical effectiveness and safety profiles for all methods of management of miscarriage. Conclusions: Our trial showed that pre-treatment with mifepristone followed by misoprostol resulted in a higher rate of resolution of missed miscarriage than misoprostol treatment alone. Women were largely satisfied with medical management of missed miscarriage and would choose it again. The mifepristone and misoprostol intervention was shown to be cost-effective in comparison to misoprostol alone. Trial registration: Current Controlled Trials ISRCTN17405024. Funding: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 68. See the NIHR Journals Library website for further project information.

Background: Progesterone is essential for a healthy pregnancy. Several small trials have suggested that progesterone therapy may rescue a pregnancy in women with early pregnancy bleeding, which is a symptom that is strongly associated with miscarriage. Objectives: (1) To assess the effects of vaginal micronised progesterone in women with vaginal bleeding in the first 12 weeks of pregnancy. (2) To evaluate the cost-effectiveness of progesterone in women with early pregnancy bleeding. Design: A multicentre, double-blind, placebo-controlled, randomised trial of progesterone in women with early pregnancy vaginal bleeding. Setting: A total of 48 hospitals in the UK. Participants: Women aged 16–39 years with early pregnancy bleeding. Interventions: Women aged 16–39 years were randomly assigned to receive twice-daily vaginal suppositories containing either 400 mg of progesterone or a matched placebo from presentation to 16 weeks of gestation. Main outcome measures: The primary outcome was live birth at ≥ 34 weeks. In addition, a within-trial cost-effectiveness analysis was conducted from an NHS and NHS/Personal Social Services perspective. Results: A total of 4153 women from 48 hospitals in the UK received either progesterone (n = 2079) or placebo (n = 2074). The follow-up rate for the primary outcome was 97.2% (4038 out of 4153 participants). The live birth rate was 75% (1513 out of 2025 participants) in the progesterone group and 72% (1459 out of 2013 participants) in the placebo group (relative rate 1.03, 95% confidence interval 1.00 to 1.07; p = 0.08). A significant subgroup effect (interaction test p = 0.007) was identified for prespecified subgroups by the number of previous miscarriages: none (74% in the progesterone group vs. 75% in the placebo group; relative rate 0.99, 95% confidence interval 0.95 to 1.04; p = 0.72); one or two (76% in the progesterone group vs. 72% in the placebo group; relative rate 1.05, 95% confidence interval 1.00 to 1.12; p = 0.07); and three or more (72% in the progesterone group vs. 57% in the placebo group; relative rate 1.28, 95% confidence interval 1.08 to 1.51; p = 0.004). A significant post hoc subgroup effect (interaction test p = 0.01) was identified in the subgroup of participants with early pregnancy bleeding and any number of previous miscarriage(s) (75% in the progesterone group vs. 70% in the placebo group; relative rate 1.09, 95% confidence interval 1.03 to 1.15; p = 0.003). There were no significant differences in the rate of adverse events between the groups. The results of the health economics analysis show that progesterone was more costly than placebo (£7655 vs. £7572), with a mean cost difference of £83 (adjusted mean difference £76, 95% confidence interval –£559 to £711) between the two arms. Thus, the incremental cost-effectiveness ratio of progesterone compared with placebo was estimated as £3305 per additional live birth at ≥ 34 weeks of gestation. Conclusions: Progesterone therapy in the first trimester of pregnancy did not result in a significantly higher rate of live births among women with threatened miscarriage overall, but an important subgroup effect was identified. A conclusion on the cost-effectiveness of the PRISM trial would depend on the amount that society is willing to pay to increase the chances of an additional live birth at ≥ 34 weeks. For future work, we plan to conduct an individual participant data meta-analysis using all existing data sets. Trial registration: Current Controlled Trials ISRCTN14163439, EudraCT 2014-002348-42 and Integrated Research Application System (IRAS) 158326. Funding: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 33. See the NIHR Journals Library website for further project information.

Background: Sepsis is a leading cause of direct and indirect maternal death in both the UK and globally. All forms of operative delivery are associated with an increased risk of sepsis, and the National Institute for Health and Care Excellence’s guidance recommends the use of prophylactic antibiotics at all caesarean deliveries, based on substantial randomised controlled trial evidence of clinical effectiveness. A Cochrane review, updated in 2017 (Liabsuetrakul T, Choobun T, Peeyananjarassri K, Islam QM. Antibiotic prophylaxis for operative vaginal delivery. Cochrane Database Syst Rev 2017;8:CD004455), identified only one small previous trial of prophylactic antibiotics following operative vaginal birth (forceps or ventouse/vacuum extraction) and, given the small study size and extreme result, suggested that further robust evidence is needed. Objectives: To investigate whether or not a single dose of prophylactic antibiotic following operative vaginal birth is clinically effective for preventing confirmed or presumed maternal infection, and to investigate the associated impact on health-care costs. Design: A multicentre, randomised, blinded, placebo-controlled trial. Setting: Twenty-seven maternity units in the UK. Participants: Women who had an operative vaginal birth at ≥ 36 weeks’ gestation, who were not known to be allergic to penicillin or constituents of co-amoxiclav and who had no indication for ongoing antibiotics. Interventions: A single dose of intravenous co-amoxiclav (1 g of amoxicillin/200 mg of clavulanic acid) or placebo (sterile saline) allocated through sealed, sequentially numbered, indistinguishable packs. Main outcome measures: Primary outcome – confirmed or suspected infection within 6 weeks of giving birth. Secondary outcomes – severe sepsis, perineal wound infection, perineal pain, use of pain relief, hospital bed stay, hospital/general practitioner visits, need for additional perineal care, dyspareunia, ability to sit comfortably to feed the baby, maternal general health, breastfeeding, wound breakdown, occurrence of anaphylaxis and health-care costs. Results: Between March 2016 and June 2018, 3427 women were randomised: 1719 to the antibiotic arm and 1708 to the placebo arm. Seven women withdrew, leaving 1715 women in the antibiotic arm and 1705 in the placebo arm for analysis. Primary outcome data were available for 3225 out of 3420 women (94.3%). Women randomised to the antibiotic arm were significantly less likely to have confirmed or suspected infection within 6 weeks of giving birth (180/1619, 11%) than women randomised to the placebo arm (306/1606, 19%) (relative risk 0.58, 95% confidence interval 0.49 to 0.69). Three serious adverse events were reported: one in the placebo arm and two in the antibiotic arm (one was thought to be causally related to the intervention). Limitations: The follow-up rate achieved for most secondary outcomes was 76%. Conclusions: This trial has shown clear evidence of benefit of a single intravenous dose of prophylactic co-amoxiclav after operative vaginal birth. These results may lead to reconsideration of official policy/guidance. Further analysis of the mechanism of action of this single dose of antibiotic is needed to investigate whether earlier, pre-delivery or repeated administration could be more effective. Until these analyses are completed, there is no indication for administration of more than a single dose of prophylactic antibiotic, or for pre-delivery administration. Trial registration: Current Controlled Trials ISRCTN11166984. Funding: This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 54. See the National Institute for Health Research Journals Library website for further project information.

(Abstracted from N Engl J Med 2019;380:1815–1824) The hormone progesterone plays a critical role in preparing the endometrium for implantation of the embryo and continues to be produced throughout pregnancy. Historically, progesterone supplementation has been initiated during early pregnancies to prevent miscarriages in asymptomatic women who have a history of recurrent miscarriages or to rescue a pregnancy in women who have started to bleed during early pregnancy.