Aim: Management of threatened preterm labour (TPL) frequently involves tocolytic drug administration, which may lead to unnecessary interventions and maternal complications, especially in women at low risk of imminent preterm birth. Cervical length measurement is a reliable method for assessing preterm birth risk and guiding appropriate management. However, tocolytic drugs and antenatal corticosteroids are often overused in women with adequate cervical length. Methods: This randomised controlled trial compared the effectiveness of bed rest versus tocolytic therapy in women with threatened preterm labour and a cervical length ≥ 20 mm. Participants were allocated to either bed rest or tocolytic treatment. Primary outcomes included preterm delivery rates and birth weight. Secondary outcomes were caesarean section rates, antenatal corticosteroid use, maternal complications, and healthcare costs. Results: Women receiving tocolytic therapy had a significantly higher rate of antenatal corticosteroid use (79%, p < 0.0001) and increased caesarean section rates compared with those managed with bed rest. Birth weight was higher among the bed rest group. No differences were found in preterm delivery rates or maternal complications between groups. Conclusion: Bed rest alone is sufficient for managing threatened preterm labour in women with a cervical length ≥ 20 mm. The use of tocolytic drugs in this low-risk population may result in unnecessary interventions, higher caesarean rates, and increased healthcare costs. Bed rest is a safe, effective, and cost-efficient alternative to pharmacologic therapy in preventing preterm delivery while minimising maternal complications. Trial Registration Page: https://www.thaiclinicaltrials.org/show/TCTR20200617001 : 17/06/2020. Plain Language Summary: Preterm labour is defined as regular uterine contractions that begin before 37 weeks of pregnancy and may lead to early birth. Doctors often give medicines called tocolytics to try to stop uterine contractions, although these medicines do not always prevent preterm birth. These drugs can sometimes cause unnecessary side effects for the mother—especially when the risk of early birth is low. Measuring the length of the cervix using ultrasound helps identify which women are more likely to deliver early. This study compared two ways of managing women with threatened preterm labour whose cervix was not very short (20 millimetres or more): bed rest only or treatment with tocolytic drugs. Women were randomly assigned to one of the two groups. Researchers looked at how often preterm birth occurred, how many caesarean deliveries were performed, the babies’ birth weights, use of steroid injections for the baby’s lungs, and any side effects or extra medical costs. The results showed that women who received tocolytic drugs had more unnecessary steroid injections and more caesarean sections. Babies in the bed rest group had slightly higher birth weights, and the rates of preterm birth and complications were similar in both groups. Overall, the study found that bed rest alone was safe and effective for women with threatened preterm labour and a cervical length of 20 mm or more. Avoiding unnecessary tocolytic treatment can reduce medical risks for mothers and help lower healthcare costs. Keywords: antenatal corticosteroids, bed rest, cervical length, preterm birth prevention, threatened preterm labour, tocolytic drugs
Chawanpaiboon et al. (Sun,) studied this question.