Prospective Assessment of Pregnancy Intentions Using a Single‐ Versus a Multi‐Item Measure

Among industrialized countries, the United States continues to have the highest rate of unintended pregnancy; approximately half of all American women aged 15–44 have experienced at least one unintended pregnancy.1 These pregnancies have well-documented health and economic consequences for mothers, children and society as a whole, including an increased risk of morbidity among women who experience unintended pregnancies and economic and social costs in education and child welfare.2 Rates of unintended pregnancy and of abortion are disproportionately high among young women, minority women and low-income women.3 Given the public health impact of unintended pregnancy, the U.S. government’s Healthy People 2010 initiative focuses on its prevention as part of the broader goals of eliminating health disparities and improving quality of life.4 Current discourse regarding unintended pregnancy, reflected in reproductive health policies and programs, often takes the stance that the concept of unintended pregnancy is uncomplicated and self-evident, despite growing evidence that the measurement and conceptualization of unintended pregnancy has significant limitations.5–11 Some of these limitations result from interchangeable use of terms related to the “intendedness,” “wantedness” and “planning status” of pregnancies;6–8 dichotomous categorization of these concepts (as unintended or intended, unwanted or wanted, and unplanned or planned) and the universal application of the concept of unintended pregnancy to different subpopulations of women;9 others stem from significant differences between researchers and policymakers on the one hand and the women being researched on the other regarding the definitions and values of planned and unplanned pregnancies.10 In response to the drawbacks of divergent definitions of existing measures, Barrett, Smith and Wellings developed and validated a simple question sequence, the London Measurement of Unplanned Pregnancy (LMUP), to measure pregnancy planning as a multidimensional concept across diverse groups of women.11 Several studies indicate that dichotomous measures of intention do not capture the experiences of the large portion of women who are ambivalent about becoming pregnant. For example, Schwarz and colleagues demonstrated that more women were willing and able to express their ambivalence toward becoming pregnant when presented with five possible responses to a pregnancy intention question than when presented with three.12 This finding is of clinical significance, because women characterized as being ambivalent toward pregnancy use less effective contraceptive methods than nonambivalent women.12,13 In addition, the retrospective approach to assessing pregnancy intention significantly limits the accuracy of its measurement.14–16 Rates of unintended pregnancy fluctuate broadly, depending on whether pregnancy intentions are measured during a pregnancy or after a birth. Most commonly, women tend to become more accustomed to a pregnancy over time, and reports of both intention and desire for pregnancy increase with time from conception. 15–17 Only two studies12,13 have prospectively assessed pregnancy intentions, and both did so in populations of nonpregnant women. An analysis of National Survey of Family Growth data in conjunction with subsequent respondent interviews, which found that correlates of unintended births differ somewhat between prospective and retrospective studies, provides evidence for the need for more prospective studies addressing pregnancy intentions in diverse populations of women.18 Prospective assessment of pregnancy intention as a multidimensional concept may increase health care providers’ ability to identify women who are ambivalent toward pregnancy and to tailor contraceptive and preconception messages to improve population-level pregnancy outcomes. Our goal was to prospectively assess pregnancy intentions in a population of women at high risk for unintended pregnancy using two measurement strategies, and to describe the relationship between these measures, decisions regarding the outcome of the potential pregnancy and the women’s pregnancy test results.