Objective This study aimed to test the applicability and effectiveness of the enhanced informed consent form (ICF) methodology, proposed by the Strategic Initiative for Developing Capacity in Ethical Review (SIDCER), in neonatal research requiring maternal consent.

Design A single-centre open-label randomised controlled study.

Setting Antenatal care clinics at Phramongkutklao Hospital, Thailand.

Patients 234 pregnant women who were at risk of preterm labour were enrolled; 232 individuals completed the study.

Interventions The participants were randomly assigned to read either the SIDCER ICF or the conventional ICF.

Main outcome measures The participants’ understanding of essential trial-related information was assessed using 25 closed-ended questions. The primary endpoint was the proportion of the participants who obtained the satisfactory level of understanding at 80% (score of ≥20/25).

Results 72.5% (87/120) of the participants in the SIDCER ICF group and 59.8% (67/112) of the conventional ICF group achieved the primary endpoint (relative risk (RR)=1.212, 95% CI 1.005 to 1.462, p=0.041). The superiority of the SIDCER ICF over the conventional ICF was significant, particularly among the participants whose education was at the high school level or below (63.5% vs 44.1%, RR=1.441, 95% CI 1.022 to 2.030, p=0.031).

Conclusions The SIDCER ICF methodology is applicable to neonatal research requiring maternal consent. The SIDCER ICF significantly improved the understanding of pregnant women, particularly among those with lower levels of education. The present study confirms the value of the SIDCER ICF methodology in research involving individuals with a limited academic background.