Hepatitis B vaccination of high risk pregnant women: A clinical trial at Parkland Memorial Hospital

Hepatitis B infection is a major public health problem of global proportions. It is estimated that 2 billion people worldwide are infected by the Hepatitis B virus (HBV) at some point, and 350 million are chronic carriers. The Centers for Disease Control and Prevention (CDC) report an incidence in the United States of 140,000–320,000 infections each year (asymptomatic and symptomatic), and estimate 1–1.25 million people are chronically infected. Hepatitis B and its chronic complications (cirrhosis of the liver, liver failure, hepatocellular carcinoma) responsible for 4,000–5,000 deaths in America each year. ^ One quarter of those who become chronic carriers develop progressive liver disease, and chronic HBV infection is thought to be responsible for 60 million cases of cirrhosis worldwide, surpassing alcohol as a cause of liver disease. Since there are few treatment options for the person chronically infected with Hepatitis B, and what is available is expensive, prevention is clearly best strategy for combating this disease. ^ Since the approval of the Hepatitis B vaccine in 1981, national and international vaccination campaigns have been undertaken for the prevention of Hepatitis B. Despite encouraging results, however, studies indicate that prevalence rates of Hepatitis B infection have not been significantly reduced in certain high risk populations because vaccination campaigns targeting those groups do not exist and opportunities for vaccination by individual physicians in clinical settings are often missed. Many of the high-risk individuals who go unvaccinated are women of childbearing age, and a significant proportion of these women become infected with the Hepatitis B virus (HBV) during pregnancy. Though these women are often seen annually or for prenatal care (because of the close spacing of their children and their high rate of fertility), the Hepatitis B vaccine series is seldom recommended by their health care provider. In 1993, ACOG issued a statement recommending Hepatitis B vaccination of pregnant women who were defined as high-risk by diagnosis of a sexually transmitted disease. ^ Hepatitis B vaccine has been extensively studied in the non-pregnant population. The overall efficacy of the vaccine in infants, children and adults is greater than 90%. In the small clinical trials to date, the vaccine seemed to be effective in those pregnant women receiving 3 doses; however, by using the usual 0, 1 and 6 month regimen, most pregnant women were unable to complete a full series during pregnancy. There is data now available supporting the use of an "accelerated" dosing schedule at 0, 1 and 4 months. This has not been evaluated in pregnant women. A clinical trial proving the efficacy of the 0, 1, 4 schedule and its feasibility in this population would add significantly to the body of research in this area, and would have implications for public health policy. Such a trial was undertaken in the Parkland Memorial Hospital Obstetrical Infectious Diseases clinic. In this study, the vaccine was very well tolerated with no major adverse events reported, 90% of fully vaccinated patients achieved immunity, and only Body Mass Index (BMI) was found to be a significant factor affecting efficacy. This thesis will report the results of the trial and compare it to previous trials, and will discuss barriers to implementation, lessons learned and implications for future trials. ^

Systematic review of acceptance of the influenza vaccine among pregnant women

Exposure to influenza places pregnant women at risk for pneumonia and their fetus at risk for premature delivery or fatal stillbirth secondary to maternal hypoxia. Immunization rates are low among pregnant women. Influenza vaccine specific-health belief model constructs, such as cue to action messages from the health care professionals, may increase acceptance of the vaccine and improve immunization rates. A systematic review was conducted to evaluate the impact of physician recommendation upon acceptance of the influenza vaccine by pregnant women. Pregnant women were more likely to accept the influenza vaccine if they received a recommendation from their physician. These women were also more likely to accept the vaccine if they thought the vaccine protected mother and fetus against adverse effects of influenza and were less likely to accept the vaccine if they were concerned about side effects or risk to the fetus from the vaccine.^

Planning, implementation, and evaluation of an HIV -screening program for pregnant women

The purpose of this study was to evaluate the effectiveness of an HIV-screening program at a private health-care institution where the providers were trained to counsel pregnant women about the HIV-antibody test according to the latest recommendations made by the U.S. Public Health Service (PHS) and the Texas legislature. A before-and-after study design was selected for the study. The participants were OB/GYN nurses who attended an educational program and the patients they counseled about the HIV test. Training improved the nurses' overall knowledge about the content of the program and nurses were more likely to offer the HIV test to all pregnant women regardless of their risk of infection. Still, contrary to what was predicted, the nurses did not give more information to increase the knowledge pregnant women had about HIV infection, transmission, and available treatments. Consequently, many women were not given the chance to correctly assess their risk during the counseling session and there was no evidence that knowledge would reduce the propensity of many women to deny being at risk for HIV. On the other hand, pregnant women who received prenatal care after the implementation of the HIV-screening program were more likely to be tested than women who received prenatal care before its implementation (96% vs. 48%); in turn, the likelihood that more high-risk women would be tested for HIV also increased (94% vs. 60%). There was no evidence that mandatory testing with right of refusal would deter women from being tested for HIV. When the moment comes for a woman to make her decision, other concerns are more important to her than whether the option to be tested is mandatory or not. The majority of pregnant women indicated that their main reasons for being tested were: (a) the recommendation of their health-care provider; and (b) concern about the risks to their babies. Recommending that all pregnant women be tested regardless of their risk of infection, together with making the HIV test readily available to all women, are probably the two best ways of increasing the patients' participation in an HIV-screening program for pregnant women. ^

Effect of yoga and swimming on body temperature of pregnant women

Physical activity for pregnant women should be controlled and adapted in order to minimize the risk of loss of balance and fetal trauma (Davies, Wolfe, Mottola, y MacKinnon, 2003). Noninvasive technologies are required for understanding better the effects of physical activity on pregnant women. Infrared thermography allows, remotely, securely and without any contact, to measure and display accurate temperatures on the human skin.

Evidence suggesting that the odortypes of pregnant women are a compound of maternal and fetal odortypes.

Odortypes--namely, body odors that distinguish one individual from another on the basis of genetic polymorphism at the major histocompatibility complex and other loci--are a fundamental element in the social life and reproductive behavior of the mouse, including familial imprinting, mate choice, and control of early pregnancy. Odortypes are strongly represented in urine. During mouse pregnancy, an outcrossed mother's urine acquires fetal major histocompatibility complex odortypes of paternal origin, an observation that we took as the focus of a search for odortypes in humans, using a fully automated computer-programmed olfactometer in which trained rats are known to distinguish precisely the odortypes of another species. Five women provided urine samples before and after birth, which in each case appropriately trained rats were found to distinguish in the olfactometer. Whether this olfactory distinction of mothers' urine before and after birth reflects in part the odortype and hence genotype of the fetus, and not just the state of pregnancy per se, was tested in a second study in which each mother's postpartum urine was mixed either with urine from her own infant or with urine of a different, same-aged infant. Responses of trained rats were more positive with respect to the former (congruous) mixtures than to the latter (incongruous) mixtures, implying that, as in the mouse, human fetal odortypes of paternal genomic origin are represented in the odortype of the mother, doubtless by circulatory transfer of the pertinent odorants.

Relationship between body mass index and mean arterial pressure in normotensive and chronic hypertensive pregnant women: a prospective, longitudinal study

Being overweight is associated with both higher systolic blood pressure (SBP) and diastolic blood pressure (DBP) during pregnancy and increased risk of gestational hypertensive disorders. The objective of this study was to determine and quantify the effect of body mass index (BMI) on mean arterial pressure (MAP) at several time points throughout pregnancy in normotensive (NT) and chronic hypertensive pregnant (HT) women.

Can group exercise programs improve health outcomes in pregnant women? A systematic review

Current scientific evidence supports the recommendation to initiate or continue the practice of physical exercise in healthy pregnant women. Group exercise programs have positive effects in improving health and well-being, as well as social support. In order to understand the scientific evidence in this field, and the outcomes in maternal health, it has generated wide interest in exploring the studies carried out with more relevant group exercise programs. The aim of this systematic review was to evaluate the available evidence on the effectiveness of group exercise programs in improving women’s and newborns health outcomes during pregnancy. Three databases were used to conduct literature searches and strict inclusion and exclusion criteria were employed. Seventeen studies were selected for analysis. All studies were randomized control trials conducted with pregnant women that evaluated the effect of group exercise programs on the health outcomes of mother and newborn. Most studies followed a supervised structured exercise program including a main aerobic part, resistance training, pelvic floor training and stretching and relaxation sections. The significant effects of the programs are related with improved maternal perception of health status, lower maternal weight gain, improved levels of maternal glucose tolerance, improved aerobic fitness and muscular strength, lower frequency of urinary incontinence, improved sick leave due to lumbopelvic pain, fewer cesarean and instrumental deliveries, higher newborn Apgar score and faster postpartum recovery. Exercise and health professionals should advise pregnant women that aerobic group exercise during pregnancy improves a wide range of health outcomes for the women and newborn

Characterization of B cells in healthy pregnant women from late pregnancy to post-partum: a prospective observational study

BACKGROUND: B cells play a role in pregnancy due to their humoral and regulatory activities. To our knowledge, different maturational stages (from transitional to memory) of circulating B cell subsets have not yet been characterized (cell quantification and phenotype identification) in healthy pregnant women. Thus, the objective of our study was to characterize these subsets (as well as regulatory B cells) from late pregnancy to post-partum and to compare them with the circulating B cells of non-pregnant women. METHODS: In all of the enrolled women, flow cytometry was used to characterize the circulating B cell subsets according to the expression of IgD and CD38 (Bm1-Bm5 classification system). Regulatory B cells were characterized based on the expression of surface antigens (CD24, CD27, and CD38) and the production of IL-10 after lipopolysaccharide stimulation. RESULTS: Compared to the absolute counts of B cells in the non-pregnant women (n = 35), those in the pregnant women (n = 43) were significantly lower (p < 0.05) during the 3rd trimester of pregnancy and on delivery day (immediately after delivery). The percentages of these cells on delivery day and at post-partum were significantly lower than those in the non-pregnant women. In general, the absolute counts and percentages of the majority of the B cell subsets were significantly lower in the 3rd trimester of pregnancy and on delivery day than in the non-pregnant women. However, these counts and percentages did not differ significantly between the post-partum and the non-pregnant women. The most notable exceptions to the above were the percentages of naïve B cells (which were significantly higher in the 3rd trimester and on delivery day than in the non-pregnant women) and of CD24(hi)CD38(hi) regulatory B cells (which were significantly higher in the post-partum than in the non-pregnant women). CONCLUSION: According to our study, the peripheral B cell compartment undergoes quantitative changes during normal late pregnancy and post-partum. Such findings may allow us to better understand immunomodulation during human pregnancy and provide evidence that could aid in the development of new strategies to diagnose and treat pregnancy-associated disturbances. Our findings could also be useful for studies of the mechanisms of maternal responses to vaccination and infection.

Characterization of B cells in healthy pregnant women from late pregnancy to post-partum: a prospective observational study

Abstract BACKGROUND: B cells play a role in pregnancy due to their humoral and regulatory activities. To our knowledge, different maturational stages (from transitional to memory) of circulating B cell subsets have not yet been characterized (cell quantification and phenotype identification) in healthy pregnant women. Thus, the objective of our study was to characterize these subsets (as well as regulatory B cells) from late pregnancy to post-partum and to compare them with the circulating B cells of non-pregnant women. METHODS: In all of the enrolled women, flow cytometry was used to characterize the circulating B cell subsets according to the expression of IgD and CD38 (Bm1-Bm5 classification system). Regulatory B cells were characterized based on the expression of surface antigens (CD24, CD27, and CD38) and the production of IL-10 after lipopolysaccharide stimulation. RESULTS: Compared to the absolute counts of B cells in the non-pregnant women (n = 35), those in the pregnant women (n = 43) were significantly lower (p < 0.05) during the 3rd trimester of pregnancy and on delivery day (immediately after delivery). The percentages of these cells on delivery day and at post-partum were significantly lower than those in the non-pregnant women. In general, the absolute counts and percentages of the majority of the B cell subsets were significantly lower in the 3rd trimester of pregnancy and on delivery day than in the non-pregnant women. However, these counts and percentages did not differ significantly between the post-partum and the non-pregnant women. The most notable exceptions to the above were the percentages of naïve B cells (which were significantly higher in the 3rd trimester and on delivery day than in the non-pregnant women) and of CD24(hi)CD38(hi) regulatory B cells (which were significantly higher in the post-partum than in the non-pregnant women). CONCLUSION: According to our study, the peripheral B cell compartment undergoes quantitative changes during normal late pregnancy and post-partum. Such findings may allow us to better understand immunomodulation during human pregnancy and provide evidence that could aid in the development of new strategies to diagnose and treat pregnancy-associated disturbances. Our findings could also be useful for studies of the mechanisms of maternal responses to vaccination and infection.