Table 2.

Intervention characteristics.

Author	Intervention	Control Condition	Theoretical Background	Full-Protocol vs. Techniques	Length (Weeks)	Intervention Description
[64]	Share Web-based	Active; same as Share without the group activities	CBT	Techniques	8	Unguided group intervention that comprised 16 main didactic activities. It provided information on both pregnancy and the postpartum period. The intervention also included 3 postpartum bust sessions (not considered in the current study). The CBT techniques employed were the following: (1) thought restructuring; (2) mood tracking; (3) activity scheduling; (4) monitoring; (5) relaxation; (6) goal setting. Participants could also interact with other women (by posting, leaving comments or likes on their posts, and by sending direct messages) encouraging discussion among them after each lesson. Participants had a personal profile in which they could post information about themselves to increase group bonding.
[65]	Mamma Mia * Web-based	TAU	Third generation CBT	Techniques	16 #	An unguided program that included 11 sessions each, which needed to be concluded to proceed to the following lesson. Provided psychoeducational information on pregnancy in a step-by-step fashion as well as cognitive and behavioral assignments. The intervention was focused on the following: (1) providing information on the specific perinatal period; (2) working on expectancies and attitudes; (3) supporting attachment, emotion regulation, and help-seeking; (4) working on relationship satisfaction and communication skills.
[66]	Sleepio Web-based CBTI program	Active; sleep education	CBT	Full protocol	6	Digital CBT intervention was specific for insomnia symptoms and included 6 sessions. The sessions were guided by a personal agent or “virtual therapist.” New sessions could be completed only after finishing the preceding one. The interventions included: (1) behavioral components (sleep restriction, stimulus control); (2) cognitive components (e.g., cognitive restructuring, paradoxical intention); (3) progressive muscle relaxation; (4) sleep hygiene.
[67]	MUMmentum Web-based	TAU	CBT	Full protocol	4	Unguided CBT intervention specific for pregnant women showing generalized anxiety and depression symptoms. It included three lessons during which content was presented through illustrated stories displayed using slides to learn how to self-manage anxiety and depression symptoms. Overall the intervention included: (1) psychoeducation; (2) relaxation techniques; (3) thought challenging; (4) structured problem solving; (5) active planning and monitoring; (6) grade exposure; (7) assertive communication; (8) relapse prevention; (9) sleep hygiene; (10) pleasant activities; (11) self-care plans; (10) understanding intrusive thoughts and images.
[68]	Gratitude and Mindfulness Web-based	TAU	Third generation CBT	Techniques	3	The unguided intervention focused on two main components: (1) a gratitude diary that was aimed at favoring reflection on the pregnancy experience; (2) mindfulness audio tracks, particularly the body scan practice, during which the focus was placed on breathing and on paying attention to each part of the body.
[69]	Spirits Healing Smartphone-based	Active; attention control group	Third generation CBT	Full protocol	8	Revised unguided MBCT focused on perinatal depression and negative emotions and on supporting the adaptation to the body changes given by the pregnancy. It included formal mindfulness training deployed through videos, reading material, and audio tracks for guided mindfulness practices. It comprised 8 sessions focused on: (1) providing information on mindfulness; (2) increasing focus on the present; (3) supporting mindfulness of negative emotions; (4) accepting difficulties; (5) understanding that thoughts are only thoughts; (6) supporting the enjoyment of daily happiness; (7) favoring mindfulness during pregnancy and childbirth; (8) continuing mindfulness practice.
[70]	Mindfulness intervention Smartphone-based	TAU	Third generation CBT	Techniques	8	Unguided mindfulness intervention was created ad hoc by a multidisciplinary team and supported by mindfulness-trained nurses who provided technical help while monitoring for changes in the symptom levels. Four mindfulness sessions were video-recorded by the mindfulness-trained nurses and shared on a smartphone chat platform (Wechat) and supplemented by text, pictures, and audio recordings that women could review. These sessions were focused on different mindfulness practices: (1) body screening; (2) relaxation; (3) meditation. During each session, the participants reviewed what had been done in the previous session and were then introduced to new mindfulness constructs. Between-session homework was foreseen by the intervention.

Note. * = Since the intervention was structured in three phases beginning during pregnancy and terminating during postpartum, the present study only considered the first phase administered during pregnancy. ^# = approximation: the intervention started during either the 21st or 25th gestational week and terminated during the 37th gestational week for each participant.