Table 3.
Description of the interventions and protocols used in the selected studies.
| Reference | Intervention and protocol | |||||||
|---|---|---|---|---|---|---|---|---|
| Comparison group (n) | Treatment group(s) (n) | Type of essential oil used | Duration of the study | Administration method | Treatment frequency | Duration per session | Total number of sessions | |
| Inhalation aromatherapy | ||||||||
|
| ||||||||
| [18] | Control with sweet almond cold-pressed pure vegetable oil with no fragrance (NA) | (i) Carrier oil with fractionated low (NA) grade essential oil (ii) Pure essential oil (NA) |
(i) Fractionated oils of unknown purity diluted 1 : 3 in carrier oil (ii) Mixture of lavender, bergamot, and cedarwood (2 : 1 : 1) |
8 weeks | 3 drops of oil applied to a bib worn during the administration of the treatment | Daily | 15–20 min | 56 |
|
| ||||||||
| [19]∗ | Control, jojoba oil (14) | (i) 2% dilution of a mixture of essential oils (6) | (i) 0.25 rose otto essential oil and 0.75 lavender, 2% dilution of the essential oil mixture | 4 weeks | 8 drops of oil applied to a cotton pad. Subjects were instructed to smell the cotton pad for 15 min | Twice a week | 15 min | 8 |
|
| ||||||||
| [20] | Control, no intervention (6) | (i) Pure essential oil (7) | (i) Lavender (ii) Petitgrain (iii) Bergamot |
1 day | 5 drops of oil applied on a filter placed in a diffuser | Once | 5 min | 1 |
|
| ||||||||
| [21] | Control, water (20) | (i) Pure essential oil (20) | (i) Yuzu | 2 days | 10 μL oil in a cotton pad used in a diffuser set in the subject's nostrils | Twice | 10 min (sessions separated in intervals around 2.6 days) | 2 |
|
| ||||||||
| [22] | Control group which did not receive any nonpharmacological method for pain relief of labor (160) | (i) Nonpharmacological methods for pain relief of labor including showering, being in upright position, aromatherapy, and soft music without words (160) | (i) 20% lavender essential oil | During labor | 10 × 10 cm cloth impregnated with 1 mL 20% lavender essential oil which was attached to the mother's breast at the beginning of the active phase. The aromatherapy intervention was combined with other nonpharmacological interventions | Once | Duration of the active phase of labor | 1 |
|
| ||||||||
| Aromatherapy massage | ||||||||
|
| ||||||||
| [23] | Control, grape seed oil (16) | (i) Diluted essential oil (16) | (i) 9 essential oils (bergamot, lemon clary sage, lavender, roman chamomile, geranium, rose otto, sandalwood, and jasmine). A combination of essential oils chosen by the aromatherapist on each treatment session (16) | 12 weeks | 15 mL grape seed carrier oil with (4 drops) or without essential oils applied in a full body massage using gentle effleurage and petrissage | Once a fortnight | 40 min | 6 |
|
| ||||||||
| [24] | Control, no intervention (13) | (i) Aromatherapy massage (16) (ii) Massage with inert carrier oil (13) |
(i) 1% lavender essential oil diluted in sweet almond oil | 2 years | Back massage | Weekly | 30 min | 4 |
|
| ||||||||
| [25] | Usual supportive care | (i) Usual supportive care and aromatherapy massage | (i) 20 essential oils | 10 weeks | Standardized massage agreed by the therapists | Weekly | 1 h | 4 |
|
| ||||||||
| [26] | Control, no intervention | (i) Aromatherapy massage | (i) 1% massage oil containing melissa, juniper, and rosemary essential oils mixed into jojoba oil (1 : 2 : 2 ratio) | 8 weeks | Standardized massage on the back, shoulders, arms, hands, lower legs, and feet using 20–30 mL massage oil | Every two weeks | 1 h | 4 |
|
| ||||||||
| [19]∗ | Control, essential oil blend unscented white lotion (14) | (i) 2% dilution of a mixture of essential oils (8) | (i) 0.25 rose otto essential oil and 0.75 lavender, 2% dilution of the essential oil mixture | 4 weeks | Topic application of the oil or lotion on both hands with gentle strokes of homogeneous pressure and speed | Twice a week | 15 min | 8 |
|
| ||||||||
| [27] | Cognitive behavior therapy (19) | (i) Aromatherapy massage (20) | (i) 20 essential oils | 2 years | Standardized massage combined with treatment as usual (routine support) | Weekly | 1 h | Up to 8 sessions in 10 weeks |
|
| ||||||||
| [28] | Control, no intervention (30) | (i) Aromatherapy massage (30) (ii) Massage (30) |
(i) 3% oil mixture containing lavender, geranium, rose, and rosemary (4 : 2 : 1 : 1 ratio) in almond and evening primrose oil | 4 weeks | Massage in the abdomen, tights, and arms using massage oil containing essential oils or odorless liquid petrolatum. Massage was applied with clockwise circular movements and light pressure | Twice a week | 30 min | 8 |
|
| ||||||||
| [29] | Control, no intervention (12) | (i) Aromatherapy massage (13) | (i) Jojoba oil containing 2% lavender and 2% geranium essential oils | 4 weeks | Massage on the neck, shoulders, arms, back, and legs including effleurage, friction, petrissage, and vibration at a moderate pressure using 20 mL of massage oil | Twice per week | 40 min | 8 |
∗In this study, both aromatherapy modalities were tested, inhalation aromatherapy and aromatherapy massage. Therefore, the study was included in both categories in the table. NA, not available; min, minutes; h, hour.