Background: Postpartum haemorrhage (PPH) is the leading cause of maternal mortality. Uterotonics are the mainstay of PPH prevention. Objectives: To compare the efficacy of misoprostol and oxytocin for the prevention of PPH, and to evaluate the trustworthiness of trials comparing these uterotonics. Search strategy and selection criteria: Seven databases were searched for peer-reviewed literature, meeting the inclusion criteria of randomized controlled trials (RCTs) comparing misoprostol and oxytocin for the prevention of PPH. Data Collection and Analysis: Data were collected by two independent reviewers. Individual participant data (IPD) was meta-analyzed for outcomes PPH≥500mL and PPH≥1000mL. RCTs that did not share IPD were classified as trustworthy or not and were included in an aggregate data meta-analysis according to trustworthiness. Main results: Of 79 eligible RCTs, ten (12.7%) provided IPD, of which six were included. Analysis of IPD showed PPH≥500mL to be significantly higher in the misoprostol than the oxytocin group (2,022 women, aOR 1.84, 95% CI 1.43- 2.34). For PPH≥1000mL, analysis of IPD showed misoprostol and oxytocin were comparable (2022 women, OR 1.14, 95% CI 0.68- 1.91). Of the 69 studies that did not provide IPD, 23 (33.3%) were assessed as trustworthy. Analysis of trustworthy data (IPD and 23 aggregate data RCTs) showed no difference between misoprostol and oxytocin for PPH≥500mL (24,334 women, OR 1.01, 95% CI 0.69- 1.49), while misoprostol significantly increased the risk for PPH≥1000 (25,249 women, OR 1.36, 95% CI 1.16- 1.59). Conclusions: Of 79 RCTs comparing misoprostol and oxytocin for the prevention of PPH, 36.7% met trustworthiness criteria. Analysis of trustworthy data suggests oxytocin is superior to misoprostol for preventing PPH.

Objectives: To investigate the association and the potential value of prelabour fetal heart rate short-term variability (STV) determined by computerised cardiotocography (cCTG) and maternal-foetal Dopplers in predicting labour outcomes. Design: Prospective cohort study. Setting: The Prince of Wales Hospital, a tertiary maternity unit, in Hong Kong SAR. Population: Women with a term singleton pregnancy in latent phase of labour or prior to labour induction were recruited during May 2019 – November 2021. Methods: Ultrasonographic assessment of foetal growth, Doppler velocimetry and the cCTG monitoring including Dawes-Redman CTG analysis. Main Outcome Measures: Umbilical Cord arterial pH, emergency delivery due to pathological CTG during labour and neonatal intensive care unit (NICU)/special care baby unit (SCBU) admission. Results: Of the 400 cases, 34 (8.5%) women underwent emergency delivery for pathological CTG during labour. A total of 6 (1.50%) and 148 (37.00%) newborns required NICU and SCBU admission, respectively. Middle cerebral artery pulsatility index (MCA-PI) and MCA-PI z-score were significant lower in pregnancies that required emergency delivery for pathological CTG during labour compared with those who did not [1.23 (1.07-1.40) vs 1.40 (1.22-1.64), p=0.002 and 0.55 (±1.07) vs 0.12 (±1.06), p=0.049,]. Umbilical cord arterial pH was associated with STV (r = 0.107, p = 0.035) and the independent predictors for umbilical cord arterial pH were smoking (p = 0.006) and STV (p = 0.025). Conclusions: In pregnant women admitted in latent phase of labour or for induction of labour at term, cCTG STV is associated with umbilical cord arterial pH but not predictive of emergency delivery due to pathological CTG during labour.

Objectives: To assess whether adding placental growth factor (PlGF) or replacing pregnancy-associated plasma protein-A (PAPP-A) improves the first trimester combined test performance for trisomy 21. Design: Prospective observation Cohort Setting: The Chinese University of Hong Kong, China Sample: 11,518 women having a singleton pregnancy screened for trisomy 21 between December 2016 and December 2019 using the first trimester combined test. Methods: PlGF was prospectively measured and estimated term risk for trisomy 21 was calculated by 1) replacing PAPP-A with PlGF and 2) adding PlGF to the combined test which includes nuchal translucency, PAPP-A and free β-human chorionic gonadotropin (hCG). Main Outcome Measure: Screening performance, area under curve (AUC), detection rate (DR), screen positive rate (SPR) and false positive rate (FPR) Results: 29 women had trisomy 21. The combined tests DR, FPR and SPR were 89.7%, 5.7% and 6% respectively. DR when replacing PAPP-A or adding PlGF to the combined test remained unchanged. Replacing PAPP-A by PlGF increased FPR and SPR to 6.2% and 6.4% respectively. Adding PlGF to the combined test gave FPR and SPR rates of 5.5% and 5.7% respectively. Adding or replacing PlGF did not give a significant increase in AUC (p>0.48) over that of the combined test. Conclusion: Adding PlGF to the combined test or replacing PAPP-A with PlGF in the combined test did not improve trisomy 21 detection rate. Replacing PAPP-A by PlGF increased SPR, whilst adding PlGF resulted in only a marginal reduction in SPR.