Sleep Disordered Breathing, Obesity and Pregnancy Study (SOAP)

Emerging data support a link between sleep disordered breathing (SDB) and adverse pregnancy
outcomes, particularly preeclampsia. Furthermore, SDB, which is characterized by intermittent
nocturnal hypoxia-reoxygenation as well as sleep disruption, results in endothelial
dysfunction and metabolic dysregulation, the same biological pathways that have been
associated with adverse pregnancy outcomes. Obesity is a well-known risk factor for both
adverse pregnancy outcomes and SDB, and has been associated with the same aforementioned
biological aberrations. Therefore, obesity complicates the definition of a causal
relationship between SDB and pregnancy outcomes. While some classic cardiovascular risk
factors (prehypertension) are certainly relevant in pregnancy, there are also
well-established risk factors that are unique to pregnancy (uterine vascular stiffness,
placental angiogenic factors). The interplay between SDB, obesity and these unique
cardiovascular risk factors remains undefined, and this proposal aims to address this
knowledge gap. Without this data, our ability to understand how we can mitigate these risks
through the use of therapeutic interventions for SDB, such as CPAP (continuous positive
airway pressure), is compromised. To further address this knowledge gap, we will make use of
the placenta's ability to accumulate evidence of damage over time and provide a record of
maternal vascular health throughout gestation. Numerous placental lesions deriving from
maternal vascular disease have been identified and can be readily detected on placental
pathology. These lesions can provide a measure of the severity of hypoxic stress experienced
by the fetus during gestation.

The investigators' central hypothesis is that SDB is an effect modifier that increases
maternal cardiovascular risk and placental hypoxic injury in obese pregnant women, and that
CPAP treatment during pregnancy will result in an improved cardiovascular risk and placental
profile. To test this hypothesis the investigaotrs will identify a cohort of obese women both
with and without SDB. The investigators will examine SDB's impact on maternal vascular
stiffness (uterine artery Doppler), angiogenesis (pregnancy specific angiogenic factors e.g.,
sFLT-1) and metabolism (insulin resistance) across pregnancy (Aim 1). The investigators will
perform a randomized controlled trial of autotitrating- CPAP verses sham-CPAP in pregnancy to
examine the impact of CPAP treatment during pregnancy on cardiovascular risk (Aim 2) and will
explore the interplay between SDB, CPAP and evidence of maternal vascular disease and chronic
fetal hypoxia by evaluating the placental profile of obese women with and without SDB (Aim
3).

Inclusion Criteria:

- women between 14 0/7 and 20 6/7 weeks gestation at the time of their initial PSG
assessment.

- Pregnancy and current BMI >=30

- Self-reported frequent snoring (>=3x/week over past month) or self-reported
non-snorer.

Exclusion Criteria:

- diagnosis of pregestational diabetes.

- self-report a history of sleep apena and who are using or were receommended by a
physican to use a PAP device already

- twins