Sleep-Disordered Breathing in Pregnancy

Sleep-Disordered Breathing in Pregnancy

Sleep-disordered breathing (SDB) is a spectrum of abnormal respiratory events including habitual snoring and increased upper airway resistance and obstructive episodes. The uncertainties concerning the incidence and recognition of SDB during pregnancy and the importance of the issue for fetal and maternal health prompted us to screen pregnant women for SDB. The study included 312 women in the third trimester of pregnancy aged 17-46 of whom 51 were preselected, based on the results of SDB questionnaires, for a nighttime home screening using a portable ApneaLink Air device. We found that single or multiple episodes of apnea were present in 35 (69%) women. The mean apnea/hypopnea index (AHI) was 1.8 ± 1.8 episodes/h of sleep, which did not exceed the prevalence in the general young-adult female population. However, we noticed a substantial number of inspiratory airflow limitation (IFL) episodes most often accompanied by snoring and more frequent in pregnant women with a greater weight gain. IFLs, although not fulfilling the quantifiable criteria of hypopnea, raise the possibility of hardly recognizable oxygenation and cardiovascular disturbances in pregnancy, reflected in an increased risk index for SDB. We conclude that pregnancy encompasses the risk of revealing or intensifying pre-existing SDB which can jeopardize maternal and fetal health. The risk particularly applies to overweight women. We submit that women in late pregnancy should be carefully screened for possible SDB.

Associations of snoring frequency and intensity in pregnancy with time-to-delivery

BACKGROUND

Sleep-disordered breathing (SDB) is linked to adverse pregnancy outcomes. However, little is known about the association of SDB with timing of delivery. We examined the association of snoring frequency, a key SDB marker, and snoring intensity, a correlate of SDB severity, with time-to-delivery among a cohort of pregnant women.

METHODS

In this prospective cohort study, 1483 third trimester pregnant women were recruited from the University of Michigan prenatal clinics. Women completed a questionnaire about their sleep, and demographic and pregnancy information was abstracted from medical charts. After exclusion of those with hypertension or diabetes, 954 women were classified into two groups by their snoring onset timing, chronic or pregnancy-onset. Within each of these groups, women were divided into four groups based on their snoring frequency and intensity: non-snorers; infrequent-quiet; frequent-quiet; or frequent-loud snorers. Cox proportional hazard regression models were used to investigate the association between snoring frequency and intensity and time-to-delivery, adjusting for maternal characteristics.

RESULTS

Chronic snoring was reported by half of the pregnant women, and of those, 7% were frequent-loud snorers. Deliveries before 38 weeks' gestation are completed occurred among 25% of women with chronic, frequent-loud snoring. Compared with pre-pregnancy non-snorers, women with chronic frequent-loud snoring had an increased hazard ratio for delivery (adjusted hazard ratio 1.60, 95% confidence interval 1.04, 2.45).

CONCLUSIONS

Snoring frequency and intensity is associated with time-to-delivery in women absent of hypertension or diabetes. Frequent-loud snoring may have a clinical utility to identify otherwise low-risk women who are likely to deliver earlier.

Snoring during pregnancy and delivery outcomes: a cohort study

STUDY OBJECTIVE

This cohort study examined the impact of maternal snoring on key delivery outcomes such as mode of delivery, infant birth centile, and small-for-gestational age.

DESIGN

Cohort study.

SETTING

A large tertiary medical center.

PATIENTS OR PARTICIPANTS

Pregnant women in their third trimester were recruited between March 2007 and December 2010.

MEASUREMENTS AND RESULTS

Women were screened for habitual snoring, as a known marker for sleep disordered breathing. Outcome data were obtained from medical records following delivery and birth centiles were calculated. Of 1,673 women, a total of 35% reported habitual snoring (26% with pregnancy-onset snoring and 9% with chronic snoring). After adjusting for confounders, chronic snoring was associated with small-forgestational age (OR 1.65, 95%CI 1.02-2.66, P = 0.041) and elective cesarean delivery (OR 2.25, 95%CI 1.22-4.18, P = 0.008). Pregnancy-onset snoring was associated with emergency cesarean delivery (OR 1.68, 95%CI 1.22-2.30, P = 0.001).

CONCLUSION

Maternal snoring during pregnancy is a risk factor for adverse delivery outcomes including cesarean delivery and small-for-gestational age. Screening pregnant women for symptoms of SDB may provide an early opportunity to identify women at risk of poor delivery outcomes.

CLINICAL TRIALS REGISTRATION

IDENTIFIER: NCT01030003.

Sleep-disordered breathing in pregnancy: a review of the physiology and potential role for positional therapy

BACKGROUND

Sleep disordered breathing (SDB) has been shown to be associated with negative clinical sequelae such as systemic hypertension and cardiovascular disease. It has been reported in the literature that approximately 53-56 % of patients with obstructive sleep apnea (OSA) have positional OSA, known as POSA.

POTENTIAL TREATMENT FOR SDB IN PREGNANCY

These findings have led to a resurgence of positional therapy as an effective treatment for select patients with SDB. Pregnant patients can also be diagnosed with SDB, the negative consequences of which not only pertain to the patient but to the unborn fetus as well. Despite this, however, SDB is under-diagnosed in pregnant patients and research looking at SDB in pregnant patients and potential therapies are scarce.

CONCLUSIONS

This article reviews the literature regarding the physiologic respiratory changes that occur during pregnancy, SDB in pregnancy, supine hypotensive syndrome (SHS), complications and current treatments for these events and potential roles for positional therapy in pregnant women whose problems may be specifically position dependent.

Pulmonary physiology in pregnancy

This section reviews anatomic and functional changes of the respiratory system during pregnancy. Pulmonary function during exercise in pregnancy and in the obese gravida, sleep-disordered breathing during pregnancy, and pulmonary changes in the pregnant woman living at altitude are discussed in detail. Assessment of pulmonary function and interpretation of the arterial blood gas during pregnancy are also discussed.