Unintended Pregnancy Among Active-Duty Women in the United States Military, 2008

Abstract

OBJECTIVE: 

To estimate unintended pregnancy rates among a representative sample of 7,225 active-duty women in the U.S. military in 2008 and to compare these rates with 2005 and with the U.S. population.

METHODS: 

Cross-sectional data came from the 2008 Department of Defense Survey of Health Related Behaviors among Active Duty Military Personnel (Health Related Behaviors Survey). For all women and by key subgroups, unintended pregnancy rates per 1,000 women were calculated and compared with rates reported in the 2005 Health Related Behaviors Survey. Univariable and multivariable logistic regression to test for associations between unintended pregnancy and key subgroups was also performed. Finally, an age-standardized unintended pregnancy rate was calculated to adjust for differences in age composition between the military and U.S. populations for better comparison with the general U.S. rate.

RESULTS: 

Eleven percent of women reported an unintended pregnancy in the prior 12 months. The 2008 self-reported unintended pregnancy rate was 105 per 1,000 women, an increase from 2005 (97/1,000 women). Younger, less educated, nonwhite, and married or cohabitating women had significantly higher rates of unintended pregnancy compared with their counterparts. Rates did not differ between women deployed in the prior 12 months and nondeployed women. The age-standardized rate was 78 per 1,000 women (95% confidence interval 77–79), which is 50% higher than the general U.S. population (52/1,000 women).

CONCLUSION: 

Unintended pregnancy rates in the military are high and have increased in most key subgroups since the 2005 survey. Efforts are needed to help servicewomen prevent unintended pregnancy, including during deployment.

LEVEL OF EVIDENCE: 

II

In Brief

Unintended pregnancy in the military is higher compared with the general U.S. population and increased from 2005 to 2008.

In the United States, 49% of pregnancies are unintended,¹ meaning that they are mistimed, unplanned, or unwanted.² Unintended pregnancy is an important public health issue, because it may lead to negative maternal and child health outcomes, including low birth weight and preterm birth,³ lower rates of breastfeeding,^4,5 and postpartum depression.⁵ For these reasons, the U.S. Department of Health and Human Services identified reducing unintended pregnancy as a national goal in its Healthy People campaign, a set of 10-year national benchmarks and objectives for health promotion and disease prevention.⁶

Unintended pregnancy among women in the U.S. military may have additional consequences, affecting both women's careers⁷ and negatively affecting troop readiness because pregnant women cannot be deployed and must be evacuated from theater if already overseas. With 97% of women in the U.S. military of reproductive age⁷ and a growing proportion of active-duty personnel that is female,⁸ these issues are particularly salient. Data from the 2005 Department of Defense Survey of Health Related Behaviors among Active Duty Military Personnel (Health Related Behaviors Survey) indicate that unintended pregnancy rates are very high, with 54% of pregnancies unintended.⁹ The self-reported annual unintended pregnancy rate was 97 per 1,000 women, and the rate adjusted for underreporting of abortion was 117 per 1,000 women.⁹ Factors found to be significantly associated with unintended pregnancy in univariable analysis included being younger, having a lower education level, cohabitating (compared with being married), being non-Hispanic black or Hispanic (compared with non-Hispanic white), serving in the Marine Corps or Army (compared with the Air Force), and being enlisted personnel (compared with an officer).⁹

This analysis was conducted to estimate unintended pregnancy rates among a representative sample of active-duty women in the U.S. military in 2008. In addition to updating the findings from the 2005 survey and gauging progress toward reducing unintended pregnancy, the data presented here are the first to include all military branches and information about deployed women. We also performed a multivariable analysis to identify covariates associated with unintended pregnancy, and we calculated an age-standardized rate that adjusts for differences in the age composition between the military and U.S. populations, thereby facilitating comparison with the general U.S. population.

MATERIALS AND METHODS

Data from the 2008 Department of Defense Survey of Health Related Behaviors among Active Duty Military Personnel were used to calculate rates of unintended pregnancy in the prior 12 months among active-duty women. The survey was conducted by RTI International under the guidance of the Office of the Assistant Secretary of Defense (Health Affairs), TRICARE Management Activity, and the U.S. Coast Guard. This survey, conducted every 2–4 years, aims to assess potential health issues among active-duty military personnel with an emphasis on substance use and abuse, mental health, sexual health, gender-specific issues, oral health, gang involvement, hearing protection, and the military's progress in meeting the Healthy People 2010 objectives.¹⁰ The relevant variables used for this analysis were obtained from TRICARE as part of a request under the Freedom of Information Act.

Data were collected from May through July in 2008. The survey used a two-stage sample design. Each service branch (Air Force, Army, Coast Guard, Marine Corps, and Navy) selected major commands (ie, service branch subdivisions organized on a functional or geographical basis) from which to draw the first-stage sampling frame. Within each command, installations (ie, bases, posts) were selected with probability proportionate to size. Individual personnel were then sampled from each of the selected installations. Replacements for personnel unavailable at the time of data collection were drawn from a second list and were matched to the original sample members on gender and rank. Eligibility for survey participation included all active-duty military personnel except recruits, service academy students, personnel absent without official leave, and personnel who were incarcerated at the time data were collected.¹⁰

Data were collected using group survey administration at large installations, including aboard afloat ships (n=40,600) or through the mail for remote personnel (n=5,200). The total sample size was 45,800, of which 28,546 surveys were completed for an overall response rate of 62.3%. Sample weights were applied to make the sample representative of the entire active-duty military population. The survey was self-administered using a paper-and-pencil questionnaire designed for optical-mark reader scanning. Participants were informed that all responses were anonymous and confidential.¹⁰ We restricted our sample to women aged 18–44 years, resulting in a final sample size of 7,225 participants.

Analyses were performed with Stata Statistical Software 12.0 using the svy command to account for complex sampling design. Our outcome of interest was unintended pregnancy in the prior 12 months, measured by the question, “In the last 12 months did you cause or have an unintended pregnancy?” Based on this self-report, for all women and by key population subgroups (including age, education, race and ethnicity, union status, service branch, pay grade, and whether the participant was deployed in the prior 12 months), we determined the weighted number of unintended pregnancies and then divided this number by the weighted total population to obtain an unintended pregnancy rate per 1,000 women. For the overall rate and rates by service branch, 95% confidence intervals (CIs) based on the Wilson procedure without a correction for continuity were also calculated.¹¹ For all women and by key subgroups, we also reported the self-reported unintended pregnancy rates per 1,000 women from the 2005 Health Related Behaviors Survey⁹ for comparison with the rates in 2008.

In the U.S. civilian population, the unintended pregnancy rate among women aged 18–24 years is twice that of the national rate for all ages combined.¹ Because there is a greater proportion of younger women in the military compared with the civilian population, we therefore calculated an age-adjusted unintended pregnancy rate using the technique of direct standardization to increase comparability with the rate reported for the general population. U.S. population estimates were obtained from the U.S. Census Bureau population projections for women in 2006, the year on which the unintended pregnancy rate for the general U.S. population is based.¹² This adjustment provides an indication of the expected unintended pregnancy rate that the military would have if its population had the same age distribution as the general U.S. population. A directly standardized rate and 95% CI based on the gamma distribution were calculated.¹³

Finally, we conducted univariable and multivariable tests of association between unintended pregnancy in the prior 12 months and key subgroups using logistic regression. All variables were used as binary or categorical variables with reference groups selected based on sample size, meaningful comparison, or both. Missing data were excluded from these analyses. This study was approved by the Allendale investigational review board.

RESULTS

Roughly half (49%) of respondents were aged 18–4 years, 22% were 25–29 years, and 29% were 30–44 years. Most (52%) had completed some college but did not have a college degree, whereas one-fourth had a high school degree or less, and one-fourth had a college degree or higher. Fifty-two percent identified as non-Hispanic white, 26% non-Hispanic black, 11% Hispanic, and 11% as other race. Forty-eight percent of women were unmarried, 43% were married, and 9% were cohabitating. The majority (83%) of women were in the enlisted pay grade, and 17% were officers. Thirty-five percent of women reported being deployed in the prior 12 months. Eleven percent of women (n=806) reported an unintended pregnancy in the prior 12 months. Half (48%) of these women with an unintended pregnancy in the prior 12 months and 11% of women overall were unable to deploy in the prior 12 months as a result of a pregnancy (Table 1).

Table 1: Background Characteristics of Study Participants

In 2008, the self-reported unintended pregnancy rate in the prior 12 months among active-duty women was 105 per 1,000 women (95% CI 103–106). This rate overall and by most key subgroups increased in 2008 from 2005 when the self-reported rate was 97 per 1,000 women (Table 2). The age-adjusted unintended pregnancy rate for military women was 78 per 1,000 women (95% CI 77–79), which is 50% higher than the general U.S. population (52/1,000 women).

Table 2: Unintended Pregnancy in the Previous 12 Mo Among Active-Duty Women Aged 18–44 Years in the U.S. Military, by Background Characteristics, 2005 and 2008

In multivariable logistic regression, the self-reported unintended pregnancy rate in 2008 was significantly higher among younger women, women with less education, non-Hispanic black and Hispanic women (compared with non-Hispanic white women), married or cohabiting women (compared with unmarried women), and women in the Army, Marine Corps, or Navy (compared with those in the Air Force). In univariable analysis, pay grade was also a predictor of unintended pregnancy, with enlisted women having significantly higher unintended pregnancy rates compared with officers; however, in multivariable analysis, pay grade dropped from significance because it was confounded by education. Women who were deployed in the prior 12 months did not have significantly different rates of unintended pregnancy compared with nondeployed women (Table 2).

DISCUSSION

Unintended pregnancy increased in the military between 2005 and 2008 when the last Health Related Behaviors Survey was conducted, especially for certain branches of the military. Younger, less educated, nonwhite, and married or cohabitating women in the military had significantly higher rates of unintended pregnancy compared with reference groups; these findings are similar to data from the general U.S. population.¹ Unintended pregnancy rates were also significantly higher for women in the Army, Marine Corps, and Navy compared with those in the Air Force. These findings highlight an important public health problem within the military that has not been adequately addressed.

Our findings also illustrate how unintended pregnancy affects deployment and ultimately troop readiness. There is little information on pregnancy or unintended pregnancy during deployment; however, a longitudinal analysis of a deployed U.S. Army Brigade Combat Team over 15 months during Operation Iraqi Freedom found that 10.8% of women were medically evacuated for pregnancy-related reasons.¹⁴ Half of women with an unintended pregnancy in the prior 12 months and 11% of women overall in the 2008 Health Related Behaviors Survey reported being unable to deploy in the prior 12 months as a result of pregnancy. Furthermore, women deployed in the prior 12 months did not have significantly different rates of unintended pregnancy compared with nondeployed women. These data indicate that unintended pregnancy occurs among women in all phases of their military careers, while stationed at their home base, while preparing for deployment, and during deployment, and that efforts to improve pregnancy prevention among all active-duty servicewomen are needed.

Although one might anticipate unintended pregnancy rates to be lower in the military compared with the general U.S. population as a result of better access to most health care services at no cost,¹⁵ the opposite appears to be true. The age-adjusted unintended pregnancy rate in 2008, 78 per 1,000 women, is 50% higher than the rate for the general U.S. population, 52 per 1,000 women,¹ which is already high in comparison to other countries.¹⁶ These high rates of unintended pregnancy in the military are particularly worrisome given the limited options available to servicewomen. In the general U.S. population, 43% of unintended pregnancies end in abortion.¹ Federal law only allows abortion to be performed at military facilities and covered under TRICARE military insurance when the pregnancy threatens the life of the woman or results from rape or incest.^17,18 Women who are deployed, especially in countries like Afghanistan, where abortion is legally restricted,¹⁹ cannot access abortion services off-base in most cases and must be evacuated out of theater if they wish to terminate an unwanted pregnancy.⁷ Faced with a desperate situation, some women deployed abroad even consider unsafe means of self-inducing an abortion.⁷

There are a number of factors that likely contribute to the high rates of unintended pregnancy in the military. Although most forms of contraception are covered under TRICARE,¹⁷ a survey of women's health experiences during deployment found a number of barriers to access. The majority of respondents were not counseled on contraception for pregnancy prevention or menstrual suppression as part of their predeployment preparations, and some faced barriers to accessing a method while overseas. These overseas barriers included care-seeking stigma and logistic obstacles that made it challenging to visit a health care provider as well as a limited amount of contraceptive supplies given at a time to women for deployment.²⁰ Another factor deterring some women from seeking contraception was confusion about prohibition of sexual activity.²⁰ Although consensual sexual activity among members of the same rank is legal, current military regulations make sexual relationships a chargeable offense in a number of circumstances.^20,21 Confusion or concern about these laws led some women to believe they could not access contraception or would not need contraception.²⁰ Another factor that may contribute to the high rates is the high prevalence of sexual assault. An estimated 20–43% of servicewomen experience rape or attempted rape during their military career,²² and the Department of Defense estimates that 86% of incidents are never reported.²³

Some branches of the military have begun to address the high rate of unintended pregnancy. For example, in the Navy and Marine Corps, the Sexual Health and Responsibility Program was created to reduce the occurrence of sexually transmitted infections and unplanned pregnancies among Navy members and families to levels specified in the Healthy People 2010 Objectives.²⁴ Efforts to address unintended pregnancy within all military branches are needed. Additionally, clinicians outside of the military should be sensitized to this issue, because servicewomen do not always receive all medical care through military health care providers. For example, research has shown that servicewomen sometimes access predeployment contraception from private clinicians, yet they may not be given supplies that last their full deployment or they may not be able to access the prescribed method through the military once overseas.²⁰

This study has several limitations. The 2008 Health Related Behaviors Survey did not ask about any pregnancy in the prior 12 months, so we were unable to calculate the proportion of pregnancies that were unintended. However, unless the overall pregnancy rate increased substantially among active-duty servicewomen since the 2005 Health Related Behaviors Survey, which is unlikely, we see no evidence to suggest a reduction in the proportion of pregnancies that are unintended. Additionally, unlike the previous analysis of the 2005 Health Related Behaviors Survey data⁹ and estimates from the general U.S. population,²⁵ we did not adjust our unintended pregnancy rates for abortion underreporting and so our rates likely underestimate the true incidence of unintended pregnancy. The strengths of this study include its large, representative sample from across all branches of the military.

Unintended pregnancy is a serious public health issue that has bearing on a woman's right to choose when and if she has a child. Unintended pregnancy among active-duty servicewomen has the additional effect of adversely affecting troop readiness, because pregnant women cannot be deployed or must be evacuated from theater. All branches of the military need to address this problem in a comprehensive manner that includes education and evidence-based provision of contraception in the context of confidential health services as well as improved access to abortion care, a right to which all U.S. women are entitled.