<![CDATA[Limited knowledge of vitamin D requirements may hinder appropriate nutritional practices during pregnancy. However, mid-upper arm circumference (MUAC) is an anthropometric indicator of maternal nutritional status rather than a biomarker of vitamin D status. This study examined changes in knowledge of vitamin D requirements and MUAC following video-based education among pregnant women. A quasi-experimental study with a non-equivalent control-group design included 69 pregnant women recruited through total population sampling at the Aur Duri Public Health Center, Jambi City, Indonesia. Participants were non-randomly allocated according to antenatal care schedule clusters to either the intervention group (n = 35) or the control group (n = 34). The intervention consisted of a 4-minute 5-second educational video shown twice and made available via WhatsApp throughout an eight-week follow-up period, while the control group received standard antenatal care. Knowledge was assessed using a 15-item questionnaire developed from national guidelines, although formal psychometric validation of the instrument was not documented. MUAC was measured using a standardized protocol. Linear mixed-effects models were used to estimate between-group differences, adjusting for baseline outcome values, maternal age, gestational age, employment status, and parity. The study received ethical exemption (No. LB.02.06/2/0838/2025), and all participants provided written informed consent. The unadjusted between-group difference in change was 3.07 points for knowledge (95% CI: 2.57–3.57; p < 0.001) and 0.43 cm for MUAC (95% CI: 0.27–0.59; p < 0.001). After adjustment, the corresponding between-group differences were 3.04 points for knowledge (95% CI: 2.52–3.56; p < 0.001) and 0.41 cm for MUAC (95% CI: 0.24–0.59; p < 0.001). Video-based education was associated with greater short-term improvements in knowledge of vitamin D requirements and MUAC than standard antenatal care. However, given the non-randomized allocation and the absence of serum 25-hydroxyvitamin D measurements, the observed difference in MUAC should not be interpreted as evidence of improved vitamin D status.]]>
