Table 1. Summary of clinical trials that assessed the effect of non-pharmacological strategies for improving sleep quality.
| Study ID | Country | Year | Sample size, N | Participant criteria | Intervention | Instrument | ||
|---|---|---|---|---|---|---|---|---|
| Intervention | Control | Strategies/Intervention | Duration | |||||
| Özkan and Rathfisch 23 | Turkey | 2018 | 42 | 42 | 3rd trimester, ≥ 20 y, primiparous, singleton, HRP, GA 28–34 weeks, pre-pregnancy BMI ≤ 25 kg/m 2 , neck circumference < 38 cm, and no RLS. | Listening to a relaxation exercises CD before sleeping. The CD comprised a 4-minute introduction, 10-minute of information on deep relaxation PE and points to consider during PE, 30-minute introduction to relaxation, and the last 30 minute includes relaxation music. | 4 weeks | PSQI |
| Pour et al. 24 | Iran | 2018 | 50 | 50 | 20–45 y, singleton pregnancy, GA 12–36 weeks, with insomnia and PSQI score > 5. | IG received capsules containing 1000 mg of lettuce seed daily. CG received placebo capsules containing starch. | 2 weeks | PSQI |
| Rodriguez-Blanque et al. 22 | Spain | 2018 | 67 | 67 | GA 12–20 weeks, without any absolute contraindications for PE * . | IG took part in the SWEP program, performing three 1-hour sessions/week water exercises. CG followed the usual recommendations, including emphasis on the positive effects of PE. | 17 weeks | PSQI |
| Sönmez and Derya 25 | Turkey | 2018 | 64 | 64 | Diagnoses of RLS, literate, at 3rd trimester, HRP, using iron supplementation, without sleep disorder. | IG received sleep hygiene training. A sleep hygiene training booklet was issued after training, and 2 weeks later, during a home visit, participants received a counseling service on sleep hygiene. | 4 weeks | PSQI |
| Kocsis et al. 19 | Romania | 2017 | 79 | 53 | HRP, 18–40 y, GA 18–22 weeks, BMI < 35 kg/m 2 , parity < 3. | IG followed a specific PE program under strict instruction by a PE training specialist. The PE program structure involved 2-hour training sessions twice a week. PE included posture correction, preserving muscle tone, and strengthening pelvic and posterior muscles, breathing exercises, and relaxation techniques. | 10 weeks | CDQ ** |
| Neri et al. 18 | Italy | 2016 | 134 | 101 | HRP, singleton pregnancy, ability to understand Italian, with feelings of anxiety and poor sleep quality. | IG was advised by a midwife (trained by an expert acupuncturist) to wear a soft rubber pin kept in place by an adhesive plaque able to exert acupressure on Point 7 of the heart meridian. | 2 weeks | PSQI |
| Shobeiri et al. 20 | Iran | 2016 | 42 | 44 | PSQI score > 5, 18–35 y, GA 30–34 weeks, singleton pregnancy, no drug addiction, not taking drugs affecting sleep quality, avoiding antidepressants use, without mental/physical disorders, access to an audio player at home. | IG received music therapy counseling in two weekly sessions, with each session lasting 60 minutes, in groups of 5–7 people. The music therapy method was passive music-listening (instrumental music by Kitaro, a Japanese composer and performer). | 4 weeks | PSQI |
| Liu et al. 21 | Taiwan | 2016 | 61 | 60 | PSQI score > 5, > 18y, GA 18–34 weeks. | IG was instructed to listen to at least one disc (30-minute) of the five prerecorded CDs compiled by the researcher or a minimum 30 minute of their preferred music per day at bedtime for 2 weeks. CG received the usual prenatal care. | 2 weeks | Chinese version of the PSQI |
Abbreviations: BMI, body mass index; CD, compact disk; CDQ, custom-designed questionnaire; CG, control group; GA, gestational age; HRP, habitual risk pregnancy; IG, intervention group; PE, physical exercise; PSQI, Pittsburgh Sleep Quality Index; RLS, restless legs syndrome; SWEP, study of water exercise in pregnancy.
*
Described by the American College of Obstetricians and Gynecologists.
**
Involved general perception of sleep quality and quantity, number of awakenings, difficulty falling asleep, insomnia, restless sleep, snoring, diurnal sleep, and consequences of inadequate sleep.