Exercise in Pregnancy for Reduction of Blood Pressure in Obese Patients

Exercise Intervention in Pregnancy for Reduction of Blood Pressure in Obese Gravidas

Preeclampsia and other high blood pressure disorders of pregnancy are a significant cause of both maternal and fetal complications of pregnancy. To date, there is no known "cure" for preeclampsia, but studies have shown that exercise may lower the risk of preeclampsia and high blood pressure disorders in pregnancy. Resistance training also lowers blood pressure, and may be easier to perform in a pregnant population, leading to higher compliance. The investigators propose to perform a novel prospective study of a resistance training regimen on blood pressure in pregnant patients at high risk for developing preeclampsia or high blood pressure.

Study Overview

• Status: Completed
• Conditions: Hypertension; Pregnancy; Exercise; Preeclampsia
• Intervention / Treatment: Behavioral: Exercise support; Behavioral: Exercise intervention

Detailed Description

Hypertension affects 5-10 percent of pregnancies, and complications from hypertensive disorders of pregnancy are the third leading cause of maternal death in the United States. Hypertensive disorders of pregnancy, including preeclampsia, lead to preterm delivery, morbidity and mortality of mother, fetus, and neonate, and are a predictor of development of chronic maternal hypertension, cardiovascular disease, and renal disease. Maternal obesity is increasing dramatically in the patient population, and is an independent risk factor for hypertension and preeclampsia, increasing the risk by two- to four-fold. To date, no effective preventative measure has been found to reduce the risk of preeclampsia or hypertension in high risk pregnant patients. However, observational studies have shown that patients who exercise or who have increased physical activity before and during pregnancy have lower rates of preeclampsia, hypertension, and gestational diabetes. Exercise has been shown in numerous studies to be safe in pregnancy, and is recommended by the American College of Obstetrics and Gynecology as part of routine prenatal care. However, aerobic exercise can be viewed by patients to be difficult to perform during pregnancy, particularly when the patient is obese and at later gestations. Adherence to exercise regimens is therefore low in this patient group. Dynamic resistance training has been shown to lower mean blood pressure both acutely and long term in non-pregnant hypertensive patients, and can be performed more easily by patients with mobility issues. This intervention has not been studied in an obese pregnant population for its effects on blood pressure throughout pregnancy.

The long term goal is to develop an intervention that will reduce the barriers to exercise of obese pregnant women that will, in turn, reduce their risk of developing preeclampsia and other hypertensive disorders of pregnancy. The specific objective of this proposal is to study the effect of a structured resistance training exercise intervention on blood pressure in obese pregnant woman, who would be considered high risk for development of hypertensive disorders based on pre-pregnancy BMI. The central hypothesis is that obese pregnant patients who participate in a regular, structured resistance training exercise regimen will have a decrease in mean arterial blood pressure compared to obese pregnant patients who are strongly encouraged to do aerobic exercise (lifestyle intervention) or who participate in routine prenatal care. The investigators formulated this hypothesis, in part, based upon previous studies found in the literature performed in non-pregnant hypertensive patients. The investigators will extrapolate from the experience and methods of the collaborators, who have studied the effects of exercise on gestational diabetes.

• Study Type: Interventional
• Enrollment (Anticipated): 66
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Pennsylvania
    • Hershey, Pennsylvania, United States, 17033
      • Penn State Milton S. Hershey Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Patient's BMI must be ≥ 30 and ≤ 40.
• Established viable singleton pregnancy <13 weeks

Exclusion Criteria:

• Multiple gestations.
• Maternal diabetes established pre-pregnancy by standard guidelines
• Congenital or acquired heart disease
• Use of antihypertensive medication
• Inability to exercise
• Restrictive lung disease
• History of shortened/incompetent cervix
• History of preterm labor

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Exercise intervention	Behavioral: Exercise intervention; Group C (exercise intervention) will be given the ACOG pamphlet on exercise in pregnancy, a daily activity log, a pedometer, a resistance band, and a handout on specific exercises (type and frequency) to be performed. The study coordinator will demonstrate each exercise and then observe the participant perform each exercise to assure full understanding. In addition to wearing the pedometer for 7 days and completing the activity log, this group will also record compliance with the exercise regimen.
No Intervention: Routine prenatal care
Experimental: Exercise support	Behavioral: Exercise support; Group B (exercise support) will be given the ACOG pamphlet on exercise in pregnancy, a daily activity log, and a pedometer. This group will be asked to wear the pedometer for 7 consecutive days between Visits 1 and 2, and record daily activities.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Change in mean arterial blood pressure	<13 weeks gestation-postpartum visit

Secondary Outcome Measures

Outcome Measure	Measure Description
Proteinuria
Hypertension of pregnancy or preeclampsia
Gestational weight gain
Neonatal weight
Serum markers for hypertension risk
Activity level	Measured with activity logos
Number of steps per week	Pedometer measurement
Weight retention at postpartum visit
Mode of delivery	Vaginal versus cesarean

Collaborators and Investigators

• Sponsor: Milton S. Hershey Medical Center

Study record dates

Study Major Dates

• Study Start: November 1, 2010
• Primary Completion (Actual): July 1, 2014
• Study Completion (Actual): January 1, 2015

Study Registration Dates

• First Submitted: December 16, 2010
• First Submitted That Met QC Criteria: December 16, 2010
• First Posted (Estimate): December 17, 2010

Study Record Updates

• Last Update Posted (Estimate): January 16, 2015
• Last Update Submitted That Met QC Criteria: January 15, 2015
• Last Verified: January 1, 2015

More Information

Terms related to this study

• Keywords: Exercise; Hypertension; Pregnancy; Preeclampsia; Resistance exercise
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Pregnancy Complications; Hypertension, Pregnancy-Induced; Hypertension; Pre-Eclampsia
• Other Study ID Numbers: 33905