Literature evidenced an association of maternal obstructive sleep apnea (OSA) with significant obstetric complications. Moreover, the OSA and its effect on feto-placental circulation had not been extensively examined. Our objective is to explore the possible impact of OSA on the feto-placental indices evaluated through the Doppler study. A systematic review of the following databases was performed: PubMed, EMBASE, Cochrane Library and Google Scholar from the beginning to June 2024. Only studies that enrolled pregnant women with signs and symptoms of OSA, which analysed the feto-placental Doppler parameters, were considered eligible (PROSPERO ID: CRD42024553926). We included a total of four studies with 1715 cases of pregnant women. Various instrumental and non-instrumental diagnostic methods were adopted for OSA detection. The ultrasound exam was performed mainly in the third trimester of pregnancies, and all the studies explored the uterine Doppler parameters. Only two studies explore the foetal Doppler parameters. Non-statistical difference was found in the foetal Doppler indices in the pregnant with OSA. Only one study disclosed that OSA is related to altered uterine Doppler indices with probable placental dysfunction. This review did not evidence a significant influence of maternal OSA on foetal Doppler indices. Moreover, one large prospective study showed a possible OSA impact on uterine Doppler with a potential impairment of the placentation function. Additional studies with detailed data and larger samples are needed to throw light on this relationship and its impact on the foetal outcomes.

Head extension by cervical collar was effective in reducing the number of respiratory events during sleep and seems to be a promising second-line treatment in moderate OSA, especially in patients with positional OSA.

Effects of gestational intermittent hypoxia on maternal, fetal and offspring respiratory system. In black, effects in humans; in red, in vitro effects; in blue, effects in animal models.

Comparison of the relationship between apnea-hypopnea index and sleep position versus REM sleep in obstructive sleep apnea.

Patients with Usher syndrome type 2a experience significant sleep disturbances, including increased sleep latency, reduced sleep quality and increased variability in sleep efficiency, manifesting independently of the progressive visual impairment. These findings highlight the need to recognize sleep disturbances as a comorbidity, which is a critical step toward targeted therapeutic interventions.