Obstetrician/Gynecologists' Knowledge,Attitudes,and Practices regarding Prevention of Infections in Pregnancy

Abstract

Background:

Maternal infection during pregnancy is a well-recognized cause of birth defects and developmental disabilities, as well as an important contributor to other adverse pregnancy outcomes. The objective of the present survey was to gain information about the knowledge, attitudes, and practices of obstetrician/gynecologists regarding prevention of infections during pregnancy.

Methods:

A survey was mailed to 606 Collaborative Ambulatory Research Network (CARN) members of the American College of Obstetricians and Gynecologists (ACOG) (approximately 2% of membership). CARN members were sampled to demographically represent ACOG.

Results:

Of the 606 eligible respondents, surveys were received from 305 (response rate: 50%). Most obstetrician/gynecologists knew that specific actions by pregnant women could reduce the risk of infection. Seventy-nine to eighty-eight percent reported counseling pregnant women about preventing infection from Toxoplasma gondii, hepatitis B virus, and influenza, 50%–68% about varicella-zoster virus, Listeria monocytogenes, and Parvovirus B19, and <50% about cytomegalovirus, Bordetella pertussis, and lymphocytic choriomeningitis virus. The majority reported time constraints were a barrier to counseling, although most reported educational materials would be helpful.

Conclusions:

Knowledge was accurate and preventive counseling was appropriate for some infections, but for others it could be improved. Further studies are needed to identify strategies to increase preventive counseling.

Introduction

Maternal infection during pregnancy is a well-recognized cause of birth defects and developmental disabilities, as well as an important contributor to other adverse pregnancy outcomes, such as intrauterine growth retardation (IUGR) and preterm birth.¹ Infections with cytomegalovirus (CMV), Toxoplasma gondii, lymphocytic choriomeningitis virus (LCMV), rubella virus, and varicella-zoster virus have been shown to cause birth defects and developmental disabilities^2,3; influenza virus can increase the risk of maternal morbidity and mortality⁴; and HIV, hepatitis B virus, CMV, and T. gondii infections can cause infection and illness in the newborn.⁵ For most of these infections, promising preventive strategies are available. However, many pregnant women are not aware of the threat of infection nor are they practicing preventive strategies.^6
–8

Obstetrician/gynecologists (OB/GYNs) are an important source for information about prevention.^6

–10 To provide optimal care of pregnant women, OB/GYNs need to have adequate knowledge about infections during pregnancy, their effects on pregnancy outcomes, and available strategies for prevention. Identification of infections as risk factors for adverse pregnancy outcomes can lead to the development of prevention programs, such as those that have raised awareness and increased prevention of infection with T. gondii in pregnant women.^11

–14

The purpose of this survey is to gain information about the knowledge, attitudes, and practices of OB/GYNs regarding the prevention of infections during pregnancy. OB/GYNs can be an important source of information for women about infections during pregnancy and how to prevent them. Therefore, it is important to gain information about what OB/GYNs know about these topics and whether they are counseling their pregnant patients about them. We surveyed OB/GYNs in the United States about their knowledge of nine maternal infections that have an adverse effect on the fetus, mother, or both when occurring during pregnancy, practices of counseling patients, and attitudes about preventing infections during pregnancy. We focused on infections for which, based on current research, behavior changes on the part of the woman might help reduce risk of infection to the mother or the infant. Although many OB/GYNs know little about LCMV, we included this virus because there is a growing body of research showing that LCMV could be a cause of more adverse birth outcomes than previously thought.¹⁵ There is a large body of research available on HIV and pregnancy. Therefore, although there are clearly many behavior changes women can engage in to avoid infection with HIV, to reduce the number of questions in the survey, not every question included an item related to HIV.

Materials and Methods

Survey questions assessed risks during pregnancy, diagnosis and laboratory testing, and preventive behaviors that could reduce a woman's risk of infection. The following nine infections were addressed in the survey: T. gondii, LCMV, CMV, Listeria monocytogenes, hepatitis B virus, parvovirus B19, Bordetella pertussis, varicella-zoster virus, and influenza virus (of note, data on CMV infection were published previously¹⁶). The questions were in multiple choice format. The survey was pilot tested with 10 OB/GYNs at a university hospital in Washington, DC. The 10 OB/GYNs completed the survey and gave written feedback that was incorporated into the final survey. This survey was reviewed by both the American College of Obstetricians and Gynecologists (ACOG) and the Centers for Disease Control and Prevention (CDC) and was determined to consist of program evaluation activities only; therefore, the survey was not subject to IRB review by either agency.

In the spring of 2007, the survey was mailed to a sample of members of the ACOG Collaborative Ambulatory Research Network (CARN). The members of CARN are practicing OB/GYNs who voluntarily participate in ACOG surveys and are demographically similar to the overall ACOG membership (based on age, gender, and geographic location).

Respondents were excluded if they did not see obstetric patients or if they practiced outside of the United States. Data were analyzed at CDC using SPSS version 14.0 (Chicago, IL). CARN survey respondents were compared to all ACOG members with regard to demographic characteristics. Chi-square and Student's t tests were used for these comparisons of demographic characteristics. Analyses were tested for significance using an alpha of 0.05. Percents and 95% confidence intervals (CI) were reported for responses to survey questions.

Results

Response rate

A total of three mailings were sent. The first mailing was sent on March 9, 2007, to 787 CARN members. Two follow-up mailings were sent to those who did not respond; the second was sent on April 4, 2007, to 559 members, and the third was sent on May 7, 2007, to 408 members. In these analyses, the surveys returned by respondents who do not see obstetric patients were excluded, resulting in a total of 615 surveys. Six respondents practice outside the United States, and 3 did not indicate where they practiced; these 9 respondents were also excluded, resulting in a total of 606 respondents. Therefore, the total number of surveys mailed to eligible respondents was 606. The number of surveys returned completed or partially completed was 305, for a response rate of 50% (305 of 606). Not all respondents answered all questions.

Demographics

Respondents from the CARN sample were significantly younger (mean 46.9 years) than ACOG members (mean 48.5 years) (t = 2.62, df 32,744, p < 0.01). A chi-square analysis showed no significant difference in gender between the two groups. However, a significant difference in the overall distribution of practice location between the ACOG and responding CARN members was found (chi-square = 20.3, df = 10, p < 0.03), with fewer CARN members than ACOG members practicing in the midwest and more CARN members than ACOG members practicing in southern and western states.

Diagnosis and laboratory testing

Participants were asked about their practices regarding diagnosis and testing. One question asked OB/GYNs whether they had diagnosed each infection in pregnant women since 2003. Sixty-three percent had diagnosed hepatitis B virus infection, 39.2% had diagnosed varicella-zoster virus infection, and 26.8% had diagnosed CMV infection since 2003. Fewer than 20% had diagnosed listeriosis, toxoplasmosis, pertussis, and infection with LCMV. Participants were also asked about their testing practices for each of the nine infections. Almost 88% reported testing all pregnant patients for hepatitis B virus. Although only about 7% of OB/GYNs tested all patients for T. gondii, 70% reported testing after the patient requested a test, and approximately 45% tested after the patient reported a significant exposure. Another 39% reported testing for T. gondii if a fetal anomaly was identified. Similarly, although only 1% reported testing all patients for CMV infection, approximately 32% reported testing after the patient requested a test, and approximately 60% tested after the patient reported significant exposure. Approximately 44% reported testing for CMV infection if a fetal anomaly was identified (it was presumed that the mother, not the fetus, was tested for CMV). A similar pattern was seen for parvovirus B19 infection and listeriosis.

OB/GYNs reported testing for influenza virus and B. pertussis most commonly after patient report of exposure (40% and 47%, respectively) (it was presumed that testing occurred when symptoms were present). For LCMV, approximately 30% tested after report of exposure, 14.8% reported testing after patient request, and 14.4% tested if a fetal anomaly was suspected.

For most infections, <5% of respondents tested if there was a negative history of infection, although for varicella-zoster virus, 21% reported testing if the patient had a negative history of infection.

Knowledge and practice regarding prevention

For some infections, the respondents who reported knowing that an action could reduce the risk of infection also recommended such precautions to their pregnant patients, whereas for other infections, the responses were less consistent between knowledge and practice (Table 1). For five behaviors (avoiding cleaning cat litter boxes to prevent toxoplasmosis, cooking meat until well done to avoid toxoplasmosis, getting tested for HIV, avoiding contact with people who have chickenpox or pertussis, keeping up-to-date on vaccines to prevent a range of infections, according to published guidelines¹⁷), a high percentage knew this behavior could prevent infection or adverse effects on the fetus, and a similarly high percentage recommended the behavior to their patients.

Table 1.

Percentage of CARN Respondents Who Reported Knowledge vs. Those Who Reported Recommending Actions to Reduce the Risk of Infection During Pregnancy a

Behavior	Knowledge b % (n) (95% CI)	Recommendation c % (n) (95% CI)
Avoiding cleaning cat litter boxes	98.1 (262) (96.4–99.4)	97.7 (257) (95.3–99.0)
Cooking meat until well done	92.0 (262) (88.2–94.4)	82.2 (241) (77.0–86.6)
Getting tested for HIV	91.6 (262) (88.7–94.7)	97.1 (240) (94.4–98.7)
Avoiding contact with people who have chickenpox or pertussis	90.8 (262) (87.1–93.6)	87.0 (238) (82.3–90.8)
Keeping up-to-date on vaccines	89.7 (262) (87.1–93.6)	89.4 (235) (84.9–92.8)
Hand washing after diaper changing	89.7 (262) (86.7–93.3)	64.7 (235) (58.4–70.6)
Avoiding wild or pet rodents	88.5 (262) (84.7–91.3)	63.8 (232) (57.5–69.8)
Not sharing utensils with toddlers	58.8 (262) (51.8–63.0)	40.9 (154) (33.4–48.8)
Not getting children's saliva in eyes or mouth	55.0 (262) (49.5–60.8)	20.8 (144) (14.82–28.01)
Avoiding licking envelopes	6.1 (262) (4.2–9.9)	62.5 (16) (38.3–82.6)

Respondents were asked to check all that apply.

Percentages of OB/GYNs who knew a behavior could prevent infection out of the total number of respondents for each question.

Percentages of OB/GYNs who recommended a preventive behavior to their patients out of the number who reported knowing the action could prevent infection.

For hand washing after diaper changing (to prevent congenital CMV and most other infections found in bodily fluids), however, and avoiding wild or pet rodents (to prevent LCMV), although a high percentage of OB/GYNs knew these behaviors could prevent infection, a much lower percentage recommended the behavior to their patients. Lower percentages of OB/GYNs reported knowing that not sharing utensils with toddlers and not getting children's saliva in the eyes or mouth (to prevent congenital CMV) could help prevent infection. Of those who reported knowing these behaviors could help prevent infection, only 41% and 21%, respectively, reported recommending these behaviors to their patients.

A distracter, avoiding licking envelopes, was included to gauge the extent to which OB/GYNs who responded to this survey might be answering questions in a manner they thought was consistent with expectations. Six percent (n = 16) of OB/GYNs responded that avoiding licking envelopes could prevent infection, and of those 16, 62.5% (n = 10) reported advising their pregnant patients to avoid doing so.

Attitudes about prevention

Respondents were asked whether they agreed (i.e., strongly agree or agree) or disagreed (i.e., strongly disagreed or disagreed) with five statements about the prevention of infections during pregnancy. Approximately 96% agreed that having prepared materials would make it easier to counsel pregnant women about infections during pregnancy. Sixty-seven percent agreed that informing pregnant women about the risk of infections during pregnancy is a priority in their practice. Approximately 62% agreed that they did not have enough time during visits to include counseling about infections during pregnancy. Over a quarter (26.3%) reported that it is not possible to avoid all infections during pregnancy and that, therefore, counseling is of limited benefit; however, the majority disagreed with this statement (72.4%). A smaller percentage (14%) agreed that informing pregnant women about infections causes them needless worry, although a large majority of respondents (85%) disagreed with this statement.

Counseling about prevention of infections

Table 2 shows the percentage and 95% CI of OB/GYNs who counseled their pregnant patients about how and why to prevent specific infections during pregnancy. The majority of OB/GYNs reported counseling their pregnant patients about preventing T. gondii and hepatitis B virus infection. Approximately 68% reported they counseled their pregnant patients about preventing varicella-zoster virus infection, and approximately 60% reported counseling about prevention of L. monocytogenes infection. Less than 50% reported that they counseled their pregnant patients about how to prevent CMV, B. pertussis, and LCMV infections.

Table 2.

Percentage of Respondents Who Counsel Patients about How and Why to Prevent the Following Infections

Infection	% (n)	95% CI a
Toxoplasma gondii	87.7 (301)	83.6–91.1
Influenza	86.3 (300)	82.1–89.9
Hepatitis B virus	78.8 (297)	73.9–83.1
Varicella-zoster virus	67.9 (299)	62.5–73.0
Listeria monocytogenes	59.8 (296)	54.1–65.3
Parvovirus B19	54.7 (300)	49.0–60.2
CMV	44.2 (294)	38.6–49.9
Bordetella pertussis	32.1 (299)	27.0–37.6
LCMV	9.2 (292)	6.2–13.0

CI, confidence interval; CMV, cytomegalovirus; LCMV, lymphocytic choriomeningitis virus.

Table 3 shows the percentage and 95% CIs for how often respondents counseled their patients about preventing infections during pregnancy (e.g., at the initial examination or if the patient asked questions). The majority of OB/GYNs in this survey reported counseling their pregnant patients about preventing infections during pregnancy at their initial examination and reported counseling their pregnant patients if they asked questions. Over half (61%) counseled their pregnant patients if the OB/GYN considered the patient to be at risk for infection. Less than half, however, counseled their pregnant patients if they mentioned they were ill. Very few counseled their pregnant patients at every visit or reported they never counseled their pregnant patients about preventing infections during pregnancy.

Table 3.

How Often Respondents Reported Counseling Pregnant Women about Preventing Infections During Pregnancy a

How often counseled	%	95% CI b
At the initial examination	78.0	73.1–82.4
If the patient asks questions	73.4	68.3–78.2
If I consider the patient to be at high risk	60.7	55.2–66.0
If the patient mentions she was ill	43.6	38.1–49.2
At every visit	2.3	1.0–4.5
Never	1.0	0.3–2.6

Respondents were asked to check all that apply.

CI, confidence interval.

Respondents were also asked who else in their practice, besides themselves, counseled pregnant women about preventing infections during pregnancy. Over 77% reported other physicians or nurses, approximately 40% reported nurse-midwives, and 34% reported office staff counseled pregnant women about preventing infections during pregnancy. Twenty-three percent reported that only the OB/GYN counseled pregnant women, and 5.5% reported that “other” persons did the counseling in their practice.

Preferred educational support tools

Respondents were asked which of five types of educational support tools they would find useful in counseling their pregnant patients about preventing infections during pregnancy. They indicated whether they would find the materials very useful, somewhat useful, not useful, or they did not know. The majority of respondents (93.7%) reported that pamphlets would be very useful or somewhat useful. Over 70% reported that downloadable, web-based materials or in-office posters would be useful or somewhat useful. Approximately 66% reported that an information package with a freebie (incentive item) would be very or somewhat useful. Approximately 39% reported that an in-office video would be very or somewhat useful; however, over 50% reported that an in-office video would not be useful.

Respondents were also asked if they would prefer individual educational materials on how to prevent each infection or a single educational material with bundling of prevention messages for all infections. Ninety percent preferred bundling of materials to cover all infections.

Discussion

Infections during pregnancy are a known cause of birth defects, developmental disabilities, and other adverse outcomes in infants and children. For many of these infections, there are behavioral changes that women can make to decrease the risk of infection.^18

–24 Although OB/GYNs play an important role in preventing infections during pregnancy by recommending specific testing or vaccines, another key activity is to serve as a source of accurate information to pregnant women about behaviors that can prevent certain infections during pregnancy. Table 4 summarizes the recommendations from CDC and ACOG regarding testing and prevention of the nine infections discussed in this paper and HIV.

Table 4.

CDC and ACOG Recommendations for Routine Testing/Screening and Prevention of Infections During Pregnancy

	CDC a		ACOG
Infection	Testing	Prevention	Testing	Prevention
Toxoplasma gondii	Can test if exposure suspected or known	Counseling recommended	Routine testing not recommended; can test if exposure suspected or known	Counseling recommended
Hepatitis B virus	Routine testing recommended	Vaccination recommended for at-risk patients	Routine testing recommended	Vaccination recommended for at-risk patients
Varicella-zoster virus	Prenatal assessment for evidence of immunity recommendedb Testing can be performed if patient has no evidence or prior immunity	Preexposure: Immunization contraindicated during pregnancy Postexposure: Exposed pregnant women who do not have evidence of immunity should be strongly considered for varicella-zoster immune globulin within 5 days of exposure	Recommended if exposed to varicella-zoster virus and patient has negative history of prior infection	Preexposure: Immunization not recommended in pregnant women Postexposure: Exposed pregnant women who do not have evidence of immunity should be considered for varicella-zoster immune globulin within 4 days of exposure
Listeria monocytogenes	Testing advised if symptoms apparent	Behavioral guidelines for women	Routine testing not recommended	Behavioral guidelines for women
Parvovirus B19	No specific recommendations	Behavioral guidelines for women	Routine testing not recommended	Counseling recommended
CMV	Routine testing not recommended; can test if exposure suspected or known	Counseling recommended	Routine testing not recommended	Counseling recommended
Bordetella pertussis	Routine testing not recommended; can test if symptoms occur following exposure to a suspected or confirmed case	Tdap is encouraged during preconception wellness visits or immediate postpartum period before leaving hospital or birthing center.c	Routine testing not recommended; can test if symptoms occur following exposure to a suspected or confirmed case	Tdap is encouraged during preconception wellness visits or immediate postpartum period before leaving hospital or birthing center.c
LCMV	No specific recommendations	Behavioral guidelines for women	No specific recommendations	No specific recommendations
HIV	Routine testing recommended	Counseling recommended	Routine testing recommended	Counseling recommended
Influenza	No specific recommendations	Vaccination recommended for women who will be pregnant during influenza season	No specific recommendations	Vaccination recommended for all women who will be pregnant during flu season

CDC, Centers for Disease Control and Prevention; ACOG, American College of Obstetricians and Gynecologists; CMV, cytomegalovirus; LCMV, lymphocytic choriomeningitis virus

For pregnant women, evidence of immunity to varicella includes any of the following: history of disease; evidence of vaccination; laboratory evidence of immunity or disease.

In certain situations, Tdap (Tetanus, diphtheria and perfussis) might be warranted. Healthcare providers who choose to administer Tdap during pregnancy should discuss with the women the lack of evidence of safety and effectiveness for the mother, fetus, pregnancy outcome, and the lack of evidence of the effectiveness of transplacental maternal antibodies to provide early pertussis protection to the infant. Women should also be informed that no study has examined the effectiveness of transplacental pertussis antibodies induced by Tdap on the adequacy of the infant immune response to pediatric DTaP (Diptheria and Tetanus toxoids and a cellular Perfussis) and conjugate vaccines containing tetanus toxoid or diphtheria toxoid. Because adverse outcomes of pregnancy are most common in the first trimester, vaccinating pregnant women with Tdap during the second or third trimester is preferred to minimize the perception of an association of Tdap with an adverse outcome, unless vaccine is needed urgently.

In the present survey, the majority of OB/GYNs appeared knowledgeable about many infections during pregnancy that can have adverse effects on pregnant women, their fetus, or both. They also were knowledgeable about the behaviors recommended by CDC and ACOG that pregnant women can engage in to avoid such infections. For many of the recommendations, however, although physician knowledge was high, frequency of counseling was lower. Skepticism about the importance or effectiveness of counseling was not a reported barrier. Consistent with several other studies about counseling to prevent adverse health outcomes,^25

–28 lack of sufficient time was the most cited barrier to counseling pregnant women about preventing infections. Most OB/GYNs reported that educational materials would assist them in this activity.

OB/GYNs reported that they provided counseling on infections of which very few women are aware. For example, 44% of OB/GYNs reported counseling women about how to prevent CMV, although the literature shows that as few as 14% of all women in the United States are aware of CMV.^6,7 In addition, only 12%–13% of pregnant women report getting the influenza vaccine,²⁹ despite the recommendation that women who could become pregnant during influenza season be vaccinated. One possible explanation for these discrepancies is that the materials and counseling techniques currently being used might not be effective. It is also possible that the OB/GYNs who responded to this survey overreported how much they counseled. Future research should confirm these possibilities as well as explore effective educational materials and methods for counseling and should include other healthcare professionals, such as nurse practitioners.

The survey asked OB/GYNs about different types of activities for which different strategies might be appropriate. Several questions focused on whether OB/GYNs counseled women about behaviors that could prevent infection, whereas others focused on whether OB/GYNs performed testing for certain infections. Most OB/GYNs followed recommended guidelines for testing practices fairly closely. Given the limits on OB/GYNs' time, educational efforts directly oriented toward pregnant women themselves might enhance prevention efforts.

The complexity of health behavior is undisputed in the field of public health and medicine.³⁰ The individual's knowledge about and awareness of the preventive behavior are essential to behavior change.^31,32 Physicians are often cited as a trusted source for health information.³³ Women are more likely to change their behavior based on advice from a physician,³³ which has important implications for the prevention of infections during pregnancy. Women lack knowledge about many infections and their effects on pregnancy. Physician-patient counseling in general can help increase healthy behaviors,^34,35 and counseling about the preventive behaviors before and during pregnancy has been shown to improve the likelihood of behavior change.³⁶ Therefore, it is critical that OB/GYNs and other healthcare professionals who care for pregnant women are educated about infections and their prevention and counsel their patients about preventive behaviors.

This survey helps to guide future efforts for educating OB/GYNs about infections during pregnancy, their diagnosis and laboratory testing, and preventive strategies. It also serves to inform public health professionals about which educational materials might assist OB/GYNs in their counseling of patients about these infections. The results of this survey show that the majority of OB/GYNs prefer one educational material that covers many of the infections and their prevention instead of separate materials that focus on individual infections. The physicians also reported a preference for educational materials in a pamphlet format. An example of a pamphlet that combines information on prevention of multiple infections during pregnancy can be found on CDC's websites at www.cdc.gov/ncbddd/pregnancy_gateway/infection.htm

Limitations to this survey include the fact that OB/GYNs who participated may not have been representative of all OB/GYNs in the United States. For example, those who responded might have been more knowledgeable about preventing infections during pregnancy than those who did not respond. As in any survey, the OB/GYNs who participated in the present survey may have responded in a manner they believe to be desirable. For example, those who responded that they recommend women avoid licking envelopes might have assumed women should avoid licking any such objects to avoid infectious exposures. Similarly, approximately 4% responded they test all patients for influenza even though routine testing for influenza is not recommended. Finally, although the ACOG guidelines for prevention of some of these infections are well defined (i.e., T. gondii), for some infections (e.g., LCMV), professional guidelines regarding counseling are not available. Therefore, the correct answer may not have been entirely clear to respondents. Finally, CARN respondents were somewhat younger than ACOG members, and the overall distribution regarding practice location was somewhat different. However, the gender distribution was equivalent. It is, therefore, possible that the CARN respondents in this study are not representative of the overall ACOG membership. CARN member responses, however, provide important preliminary information for future study.

Conclusions

In this survey, the respondents' overall level of knowledge about the prevention of infections during pregnancy was high, and attitudes toward prevention were positive. The preventive counseling reported by OBGYNs was appropriate for some infections. For other infections, however, reported preventive counseling could be improved. The results of this survey emphasize the need for additional training of OB/GYNs about prevention of certain infections (e.g., CMV and LCMV). With each of these infections, prevention behaviors exist through avoidance of particular foods, animals, or high-risk behaviors and following healthy behaviors, such as hand washing, getting appropriate vaccinations, and screening for infections.

Future research should evaluate whether the materials preferred by OB/GYNs are consistent with those that women prefer and whether these materials will contribute to the targeted behavioral changes. Additional surveys of OB/GYNs should examine why physician knowledge about transmission does not necessarily result in patient counseling, attempt to identify facilitative factors associated with providing preventive counseling, solicit more detailed information about knowledge of infections during pregnancy and counseling practices, and assess perceptions related to frequency of infection and the role of testing.

Footnotes

Acknowledgments

This survey was supported by grant R60 MC 05674 from Maternal and Child Health Bureau (Title V, Social Security Act), Health Resources and Services Administration, Department of Health and Human Services.

Disclosure Statement

The authors have no conflicts of interest to report.

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