This study is testing the hypothesis of whether continuous positive airway pressure (CPAP) therapy improves placental histopathology and secretory function. The main aims of the study are to identify shared mechanisms between obstructive sleep apnea and preeclampsia, both common highly morbid conditions.

Patients will be recruited from multiple community and hospital-based practices that care for pregnant women. Subjects will be given a physical exam, have measurements taken, answer questionnaires and then will be screened using a home sleep apnea test (HSAT) Type III device. Those diagnosed with Obstructive Sleep Apnea will then be randomized to one of two groups (below).

Both groups will have:

1. blood testing for placenta-secreted circulating markers
2. placental histopathological and immunohistochemistry examination of placental expression of markers.

Both groups will answer sleep and mood questionnaires, have blood pressure, blood glucose and activity / sleep watch monitoring and will receive an educational session on pregnancy health.

Randomization groups include:

1. Nasal dilator strips: Participants receiving nasal dilator strips will be monitored by need for refill of supplies and periodic phone calls.
2. CPAP + nasal dilator strips: Subjects randomized to positive airway pressure (PAP) therapy will receive auto-titrating PAP. Pressure requirements will be monitored remotely and pressure modified as needed. PAP adherence will be determined subjectively and objectively. This group will also receive nasal dilator strips as described above.

All subjects will receive small gift incentives such as baby-related items. Monetary incentives will also be issued at data collection points.

Inclusion Criteria:

• Pregnant snorers without obstructive sleep apnea, have a BMI >30 kg/m2 at recruitment
• >18 years of age
• <13 completed weeks of gestation (confirmed by last menstrual period or early pregnancy dating ultrasound during qualification)
• Intention to reside locally and deliver at Women and Infants Hospital of Rhode Island
• Ability to give informed consent.

Exclusion Criteria:

• Unable to meet inclusion criteria, Incompetent cervix / cerclage (likelihood of severe preterm delivery affecting study aims)
• Inability to tolerate PAP therapy
• Serious physical or mental illness or condition that would affect participation
• Drowsy driving
• Severe hypoxemia on sleep study
• Advanced cardiac disease or arrhythmias that may benefit from PAP therapy
• Chronic lung disease and / or respiratory failure.
• Twin pregnancies
• Fetuses with congenital anomalies
• Severe hypertension at enrollment