The purpose of the research is to characterize the effect of labetalol, atenolol, and nifedipine on maternal hemodynamics early in pregnancy. Patients will be given medication based on their hemodynamics and asked to return for a repeat measurement.

When a patient presents to the Maternal Hypertension Center at Cabell Huntington Hospital, she will receive a non-invasive hemodynamic assessment via the NICaS system as per usual protocol. The NICaS system uses impedance cardiography which provides a reliable assessment of cardiovascular, respiratory, and fluid parameters. In typical practice, the vasodilator nifedipine is initiated for increased systemic vascular resistance and elevated cardiac output is treated with beta blockade (via either atenolol or labetalol). The medication to be given to each subject will be based on their hemodynamics. Specifically, nifedipine will be given for a mean arterial pressure >100 and a beta blocker will be given for a cardiac output >8 l/min. The patients will be asked to return in one week for repeat ICG measurement.

Inclusion Criteria:

• Patients presenting to Maternal Hypertension Center at Cabell Huntington Hospital
• English speaking
• 18-45 years old.
• Willing to provide informed consent
• Gestational age prior to 15 weeks gestation

Exclusion Criteria:

• Non-English speaking patients, patients
• <18 years old or >45 years old
• Not willing or able to provide consent
• Gestational age >15 weeks

Pregnant women

Patients presenting to the Maternal Hypertension Center at Cabell Huntington Hospital. Consent will be obtained prior to enrollment. Patient age range will be from age 18 to approximately 45.