Additional Study Information: This research study is being done to understand how CPAP for sleep apnea may affect hypertensive disorders of pregnancy and other complications of pregnancy such as gestational diabetes. The purpose of the home sleep test is to find women with sleep apnea. Sleep apnea is when you have one or more pauses in breathing or shallow breaths while you sleep. Studies have shown that women with sleep apnea have an increased risk of high blood pressure and diabetes during pregnancy. If the test shows that you have sleep apnea in the mild to moderate range you will be eligible for a research study to find out whether a treatment with CPAP (continuous positive airway pressure) reduces the chance of getting high or increasing blood pressure and other problems associated with being pregnant. We expect about 40 women will take part at this hospital.