Is There a Trend of Increased Unwanted Childbearing Among Young Women in the United States?
Article Outline
Abstract
Purpose
The majority of births to young women are unintended (either mistimed or unwanted), bearing an increased risk of poor health outcomes for both mother and child. In this analysis, we describe trends of unwanted, mistimed, and intended births reported by all women and specifically by young women in the National Survey of Family Growth (NSFG).
Methods
Using data from the 1982, 1988, 1995, and 2002 NSFG surveys, we calculated the proportion of unwanted, mistimed, and intended births by maternal age at birth. For the 1995 and 2002 NSFG surveys, we also assessed birth intentions among 15–24-year-old nulliparous women and the mean number of unwanted births in the past 5 years among all 15–24-year-old women.
Results
The proportion of unintended births decreased between 1988 and 1995 but increased between 1995 and 2002. This recent increase was attributed to the increased proportion of unwanted births reported by women <25 years of age from 10.4% in 1995 to 18.6% in 2002 (p < .01). Between 1995 and 2002, the proportion of 15–24-year-old nulliparous women who intended no future births increased from 8.1% to 10.4% (p < .05), and the mean number of unwanted births per 1000 women aged 15–24 years increased from 25 to 48 (p < .01).
Conclusions
Our analyses suggest an increasing trend in unwanted childbearing among young women between 1995 and 2002. Further research is needed to understand the meaning and causes of increased unwanted childbearing among young women and to identify characteristics of those at risk.
Keywords: Unwanted births, Women, Trends
The majority of pregnancies and births among women less than 25 years old, particularly among those aged less than 20 years, are unintended—either mistimed (occurring before they are desired) or unwanted (exceeding the number of lifetime births desired) [1], [2]. Despite recent declines in pregnancy and birth rates among women aged less than 25 years [3], [4], investigators have noted an increasing trend in the proportion of unintended pregnancies [2] and unintended births [1] among young women. The corresponding decrease in the proportion of intended pregnancies and births directly contrasts with the Healthy People 2010 goal that aims to increase the proportion of pregnancies that are intended [5].
Unintended pregnancy is an important public health issue because of its association with poor health outcomes for both mother and child. In the United States, about 50% of unintended pregnancies end in induced abortion [2], [6], and the unintended pregnancies that result in live births are associated with an increased risk of complications. Previous studies have reported that unintended pregnancies are associated with a lack of prenatal care, higher behavioral risks (such as alcohol and tobacco use), and higher rates of complications during pregnancy, birth, and the postpartum period than are intended pregnancies [7], [8], [9], [10], [11]. Failure to adopt healthy behaviors by women with unintended pregnancies negatively affects health of their infants [10], [12], [13]. Besides these health risks, unintended pregnancy has been associated with poverty, poor maternal education, domestic violence, and family disruption [7], [14], [15].
The National Survey of Family Growth (NSFG), a primary source of national data on fertility for reproductive-aged women for more than 3 decades, provides the opportunity to analyze long-term trends in pregnancy and birth wantedness. In this report, we use data from NSFG to analyze trends in childbearing by the three categories of birth planning status—unwanted, mistimed and intended—for all women of reproductive age and to describe in more detail increases in the proportion of unintended births among young women between the last two NSFG cycles.
Methods
Data were analyzed from the NSFG cycles 3 through 6 that were conducted in 1982, 1988, 1995, and 2002, respectively. The NSFG is a cross-sectional reproductive health survey conducted every 5 to 7 years using a household-based, nationally representative sample of women aged 15–44 years. In each cycle, survey respondents were interviewed in their homes. Details of the survey methodology are published elsewhere [16], [17], [18], [19]. The total number of female respondents was 7,969 in 1982, 8,450 in 1988, 10,847 in 1995, and 7,643 in 2002; the number of respondents 15–24 years old was 3,378 in 1982, 2,543 in 1988, 2,914 in 1995, and 2,513 in 2002.
We used three different approaches to assess trends in wantedness of childbearing: the proportion of births that were reported as mistimed or unwanted, compared with intended, among women who had one or more live births in the past 5 years; the proportion of women who reported that they do not intend births in the future among women who had no births (i.e., nulliparous women); and the mean number of unwanted births per 1000 women in the past 5 years.
Proportion of unwanted, mistimed, and intended births among women who had births
First, we examined the trends of unwanted, mistimed, and intended births among women who were interviewed in 1982, 1988, 1995, and 2002. We used standardized measures from NSFG to classify births in the 5 years before each survey into one of the three categories of wantedness. Specifically, classification of births as unwanted, mistimed, or intended was based on responses to questions about how the woman felt about the pregnancy at the time of conception. For each pregnancy in the past 5 years, respondents were asked about their contraceptive use before that pregnancy. If contraception was not used or had been discontinued, she was asked, “Was the reason you (had stopped/were not) using any methods because you yourself wanted to become pregnant?” If the answer was “no,” they were asked, “It is sometimes difficult to recall these things but, just before that pregnancy began, would you say you probably wanted (another) baby at some time or probably not?” Women who said they did intend to have a baby and women who said they were not using contraception because they wanted to become pregnant were asked, “Did you become pregnant sooner than you wanted, later than you wanted, or at about the right time?” For women who reported that their pregnancy occurred when they wanted to get pregnant or later than they wanted, and did not occur too soon, we classified the births as “intended.” Conversely, births that occurred when the respondent desired to have a future birth but that occurred too soon were classified as “mistimed,” and births that occurred when the woman reported that she wanted no future births in her lifetime were classified as “unwanted.” We calculated the percentage of live births in the 5 years preceding each interview by the status of the birth planning categories. This approach is consistent with the analyses of earlier cycles of the NSFG [20], [21], [22].
Although women were interviewed when they were 15 to 44 years old, we calculated proportions of unwanted, mistimed, and intended births for the three age categories (<20 years old, 20–24 years old, and 25–44 years old) of women at the time of birth. Thus, this algorithm could include a few births that occurred among young mothers aged less than 15 years. Because the unit of the analysis was the birth rather than the respondent, women could contribute more than one birth to the same or different age-at-birth categories if they had more than one live birth during the 5-year period before the interview.
After considering trends in wantedness of childbearing for all women by age group, we focused on the recent increase in the proportion of unwanted births among young women (<25 years old) between the last two NSFG cycles (1995 and 2002). For births reported by women in the 1995 (cycle 5) and 2002 (cycle 6) NSFG cycles, we assessed the proportion of unwanted births by the age of the women at birth, parity, race/ethnicity, and poverty index. We also stratified each race/ethnicity category by poverty index. Poverty index, an indicator of socioeconomic status, was based on the poverty levels defined by the U.S. Census Bureau, which take into account the number of persons in the family. For each family size, a poverty threshold level was defined, and the actual family income was compared to this value, and expressed as a percentage [21], [22].
Birth intentions among nulliparous women
To understand observed changes in the proportion of unwanted births to young women (many of which were first births), we also looked at the desired lifetime number of children. Because having an unwanted first birth may imply that at the time of the interview a woman did not ever intend to have children, we examined the birth intentions of 15- to 24-year-old nulliparous women interviewed in 1995 and 2002. Standardized recodes available with the NSFG datasets were used to classify future birth intentions as “intended” or “unintended.” This classification was based on the answer to the following question: “Looking to the future, do you intend to have a baby at some time (intend refers to what you are actually going to try to do)?” We stratified our analysis by age at interview, race/ethnicity, and poverty index. In addition, each race/ethnicity category was further stratified by poverty index.
Mean number of unwanted births among all women
To help determine whether trends in the proportion of unwanted births were attributable to an overall decrease in the number of births among young women, we assessed the changes in the number of unwanted births. Specifically, for the 1995 and 2002 cycles, we calculated the number of unwanted births that occurred in the past 5 years (numerator) among all women aged 15–24 years who were interviewed (denominator). The mean number of unwanted births was calculated per 1000 women, and this calculation took into account all women interviewed in the respective age group. The analysis was also stratified by age at interview, race/ethnicity, and poverty index. In addition, we calculated mean number of unwanted births for every poverty index level within each race/ethnicity category.
For all the analyses, we used SAS-callable SUDAAN software [23] to adjust for intracluster homogeneity within samples. Confidence intervals were adjusted for the complex sample design. Statistical significance of differences between survey cycles was assessed using a two-sided z-test of difference between independent samples.
This secondary analysis of the NSFG data was reviewed by the Centers for Disease Control and Prevention and was determined to be exempt from institutional review board review as research not involving human subjects.
Results
Proportion of unwanted, mistimed, and intended births among women who had births
Within each age group, the proportion of births that were reported as unwanted, mistimed, and intended in the past 5 years had similar distributions for each time point or NSFG cycle (Table 1). In each cycle, women who were less than 20 years old had a lower proportion of births that were intended and a higher proportion of both unwanted and mistimed births than did women in the other two age groups. In contrast, in all cycles, women in the oldest age group (25–44 years old) had a higher proportion of intended births and a lower proportion of mistimed births than did women aged less than 20 years and those aged 20–24 years. Between the 1982 and 1988 cycles, the overall small decrease in the proportion of intended births from 63.2% to 60.6%, which was not statistically significant, was likely because of a significant increase in the proportion of unwanted births among 20- to 24-year-old women from 7.3% to 11.5% (p < .05). Between the 1988 and 1995 cycles, the overall proportion of intended births increased significantly from 60.6% to 69.1% (p < .01). This was because of the decrease in the proportion of both mistimed births (from 26.8% to 20.6% [p < .01]) and unwanted births (from 12.3% to 10.1% [p < .01]). The decreased proportion of mistimed births was particularly evident among women in the oldest age group (from 18.8% to 11.0% [p < .01]). Although a decreased proportion of unwanted births was observed in all age groups, the decrease was not statistically significant in any individual age group. The proportion of intended births decreased again between 1995 and 2002 NSFG cycles (from 69.1% to 64.7% [p < .01]). This decrease was attributable to increases in the proportion of unwanted births among women aged less than 20 years (from 12.6% to 21.8% [p < .01]) and women aged 20 to 24 years (from 9.4% to 17.3% [p < .01]). The proportion of mistimed births remained stable in each of the groups.
Table 1. Percentage of births in the past 5 years by wantedness status and age at birth, NSFG surveys 1982, 1988, 1995, and 2002
| 1982 | 1988 | 1995 | 2002 | |||||
|---|---|---|---|---|---|---|---|---|
| % | 95% CI | % | 95% CI | % | 95% CI | % | 95% CI | |
| All womenc | N = 2,916 | N = 3,115 | N = 3,891 | N = 2,782 | ||||
| 10.0 | 8.4–11.6 | 12.3a | 10.8–13.8 | 10.1b | 9.0–11.2 | 14.2b | 12.4–16.0 | |
| 26.7 | 24.3–29.1 | 26.8 | 24.6–29.0 | 20.6b | 19.1–22.1 | 20.8 | 19.0–22.6 | |
| 63.2 | 60.5–65.9 | 60.6 | 58.2–63.0 | 69.1b | 67.3–70.9 | 64.7b | 62.2–67.2 | |
| Age <20 years | N = 545 | N = 411 | N = 476 | N = 343 | ||||
| 12.9 | 8.7–17.1 | 17.3 | 11.6–23.0 | 12.6 | 9.1–16.1 | 21.8b | 16.5–27.1 | |
| 56.6 | 49.3–63.9 | 54.5 | 46.7–62.3 | 52.4 | 47.8–57.0 | 56.5 | 51.1–61.9 | |
| 30.5 | 23.4–37.6 | 27.9 | 21.2–34.6 | 34.4 | 29.4–39.4 | 21.7b | 17.4–26.0 | |
| Age 20–24 years | N = 1,014 | N = 893 | N = 1,012 | N = 808 | ||||
| 7.3 | 5.1–9.5 | 11.5a | 8.7–14.3 | 9.4 | 7.5–11.3 | 17.3b | 13.9–20.7 | |
| 30.4 | 25.9–34.9 | 33.4 | 28.9–37.9 | 29.0 | 25.9–32.1 | 27.4 | 23.8–31.0 | |
| 62.1 | 57.5–66.7 | 55.1a | 50.4–59.8 | 61.2a | 58.2–64.2 | 55.1a | 50.8–59.4 | |
| Age 25–44 years | N = 1,350 | N = 1,811 | N = 2,403 | N = 1,631 | ||||
| 10.8 | 8.4–13.2 | 11.8 | 10.0–13.6 | 9.9 | 8.7–11.1 | 11.7 | 9.7–13.7 | |
| 16.7 | 13.9–19.5 | 18.8 | 16.5–21.1 | 11.0b | 9.6–12.4 | 12.1 | 10.2–14.0 | |
| 72.5 | 69.1–75.9 | 69.1 | 66.4–71.8 | 79.0b | 77.1–80.9 | 75.9 | 73.2–78.6 | |
ap < .05. |
bp < .01. Comparison between the proportion of births in a given NSFG cycle and the proportion in the preceding NSFG cycle for the same category of planning status. |
cInformation on age at birth was missing for a small number of women. |
When we restricted the sample to the last two NSFG cycles and to women aged less than 25 years (Table 2), the proportion of unwanted births was highest among women in the youngest age category (≤17 years old): 14.8% in 1995 NSFG cycle and 26.0% in 2002 NSFG cycle, when compared to older adolescents (18–19 years old, 11.4% in 1995 and 18.8% in 2002) and young adults (20–24 years old, 9.4% in 1995 and 17.3% in 2002). The increase in the proportion of unwanted births among women less than 25 years old was evident among women who were having their first birth (6.9% to 14.8% [p < .01]) and among those who were having their second or higher order birth (15.0% to 23.3% [p < .01]). In 1995, young non-Hispanic black women had the highest proportion of births that were unwanted (21.2%), which did not change significantly in 2002 (27.8%). During the same time period, however, the proportion of unwanted births among young non-Hispanic white women increased more than twofold—from 6.2% to 14.7% (p < .01); and the proportion of unwanted births among young Hispanic women increased from 10.7% to 19.8% (p < .05). Young women from families with lower income had the highest proportion of births that were unwanted. Between 1995 and 2002, the proportion of unwanted births increased among young women from all socioeconomic groups. Within each race/ethnicity category, there was a tendency toward an increase of the proportion of unwanted births among women in each poverty index subgroup.
Table 2. Percentage of unwanted births in the past 5 years among women <25 years old who gave birth(s), by parity, race/ethnicity, and poverty index 1995 and 2002 NSFG surveys
| 1995 | 2002 | |||||
|---|---|---|---|---|---|---|
| N | % unwanted | 95% CI | N | % unwanted | 95% CI | |
| Total | 1,488 | 10.4 | 8.7–12.1 | 1,151 | 18.6b | 15.4–21.7 |
| Age | ||||||
| 476 | 12.6 | 9.1–16.1 | 343 | 21.8b | 16.5–27.1 | |
| 180 | 14.8 | 9.3–20.4 | 133 | 26.0a | 18.3–33.7 | |
| 294 | 11.4 | 7.1–15.8 | 210 | 18.8 | 12.3–25.2 | |
| 1,012 | 9.4 | 7.5–11.3 | 808 | 17.3b | 13.9–20.6 | |
| Parity | ||||||
| 789 | 6.9 | 5.2–8.7 | 631 | 14.8b | 11.0–18.5 | |
| 699 | 15.0 | 11.9–18.2 | 520 | 23.3b | 19.2–27.5 | |
| Race/ethnicityc | ||||||
| 634 | 6.2 | 4.2–8.1 | 447 | 14.7b | 10.5–18.9 | |
| 332 | 10.7 | 7.0–14.3 | 358 | 19.8a | 13.5–26.1 | |
| 487 | 21.2 | 16.6–25.7 | 294 | 27.8 | 21.4–34.1 | |
| Poverty index | ||||||
| 857 | 14.5 | 11.8–17.2 | 692 | 20.7a | 16.6–24.7 | |
| 442 | 5.4 | 3.0–7.7 | 311 | 13.5b | 9.2–17.7 | |
| 189 | 7.7 | 3.5–11.9 | 148 | 19.2a | 9.6–28.8 | |
| Race/ethnicity by poverty index (PI) | ||||||
| 267 | 8.7 | 4.9–12.6 | 236 | 16.1a | 10.5–21.6 | |
| 254 | 4.1 | 1.6–6.5 | 131 | 11.0 | 4.2–17.8 | |
| 113 | 5.1 | 1.3–8.8 | 80 | 16.3 | 4.7–27.9 | |
| 222 | 13.6 | 9.2–18.1 | 234 | 20.2 | 12.0–28.4 | |
| 81 | 4.6 | 0.2–8.9 | 98 | 19.1b | 11.2–27.0 | |
| 29 | — | — | 26 | — | — | |
| 353 | 24.1 | 18.4–29.7 | 188 | 32.3 | 23.8–40.7 | |
| 93 | 14.6 | 5.9–23.3 | 70 | 15.0 | 6.3–23.7 | |
| 41 | 16.0 | 3.5–28.5 | 36 | 28.1 | 11.1–45.1 | |
ap < .05. |
bp < .01. Comparison between the proportion of unwanted births in 2002 NSFG cycle and the proportion of unwanted births in 1995 NSFG cycle. |
cThe “other” race/ethnicity category includes <5% of births for each time period and is omitted. |
dWhen <30 births are reported in a subgroup, percentage and confidence interval are not shown and a z-test not performed. |
Birth intentions among nulliparous women
The proportion of nulliparous women 15 to 24 years old who reported intending no births in the future increased from 8.1% in the 1995 NSFG cycle to 10.4% in 2002 (p < .05) (Table 3). This increase was most pronounced among women aged 15 to 17 years with 8.8% reporting intending no births in the future in 1995 and 12.9% reporting this in 2002 [p < .05]). Although nulliparous women in all race/ethnicity groups showed increases in this measure, we observed the largest increase among Hispanic women—from 5.4% in 1995 to 11.0% in 2002 (p < .01). The increase in the proportion of young nulliparous women intending no future births was especially evident in the lowest socioeconomic group, where it changed from 7.1% in 1995 to 12.1% in 2002 (p < .01). Further stratification of race/ethnicity category by poverty index revealed that among all nulliparous women who intended no future births, Hispanic women in the lowest socioeconomic group had most pronounced increase in this measure, which tripled from 4.4% in 1995 to 13.6% in 2002 (p < .05).
Table 3. Percentage of nulliparous women aged 15–24 years who intend no future births, by race/ethnicity and poverty index, 1995 and 2002 NSFG surveys
| 1995 | 2002 | |||||
|---|---|---|---|---|---|---|
| N | % | 95% CI | N | % | 95% CI | |
| Total | 2,154 | 8.1 | 6.9–9.4 | 1,889 | 10.4a | 9.0–11.9 |
| Age | ||||||
| 1,246 | 8.1 | 6.4–9.7 | 1,044 | 11.7a | 9.3–14.1 | |
| 767 | 8.8 | 6.6–11.0 | 652 | 12.9a | 10.2–15.6 | |
| 479 | 6.9 | 4.4–9.3 | 392 | 9.8 | 6.2–13.4 | |
| 908 | 8.2 | 6.4–10.0 | 845 | 8.7 | 6.9–10.4 | |
| Race/ethnicityc | ||||||
| 1,373 | 8.2 | 6.6–9.8 | 1,141 | 10.5 | 8.5–12.5 | |
| 296 | 5.4 | 3.0–7.8 | 327 | 11.0b | 7.6–14.3 | |
| 390 | 9.7 | 6.3–13.1 | 308 | 11.5 | 7.7–15.3 | |
| Poverty index | ||||||
| 501 | 7.1 | 4.6–9.6 | 593 | 12.1b | 9.3–14.9 | |
| 795 | 10.0 | 7.8–12.1 | 589 | 10.6 | 7.7–13.5 | |
| 858 | 7.0 | 5.3–8.7 | 707 | 8.9 | 6.9–11.0 | |
| Race/ethnicity by poverty index (PI) | ||||||
| 247 | 7.4 | 3.7–11.2 | 290 | 12.1 | 8.5–15.7 | |
| 483 | 10.4 | 7.6–13.3 | 350 | 11.0 | 7.4–14.7 | |
| 643 | 6.8 | 4.9–8.7 | 501 | 9.1 | 6.4–11.7 | |
| 95 | 4.4 | 0.3–8.5 | 146 | 13.6a | 7.3–19.8 | |
| 121 | 6.3 | 1.8–10.9 | 107 | 6.4 | 1.8–11.0 | |
| 80 | 5.1 | 0.8–9.4 | 74 | 12.2 | 3.8–20.5 | |
| 137 | 8.3 | 2.8–13.9 | 116 | 13.5 | 6.1–20.9 | |
| 152 | 9.2 | 3.9–14.4 | 100 | 11.6 | 5.4–17.8 | |
| 101 | 13.0 | 5.6–20.4 | 92 | 8.0 | 3.8–12.3 | |
ap < .05. |
bp < .01. Comparison between the proportion of women who intended no future births in 2002 NSFG cycle, and the proportion of women who intended no future births in 1995 NSFG cycle. |
cThe “other” race/ethnicity category includes <6% of women for each time period and is omitted. |
Mean number of unwanted births among all women
The mean number of unwanted births per 1,000 women aged 15 to 24 years nearly doubled from 25 in 1995 to 48 in 2002 (Table 4). The increase was most evident among women 20 to 24 years old, where the mean number of unwanted births per 1,000 women increased from 39 in 1995 to 80 in 2002 (p < .01). Hispanic and non-Hispanic white women also had the highest increase of the mean number of unwanted births. This number almost tripled from 32 to 93 per 1,000 Hispanic women (p < .01) and doubled from 14 to 28 per 1,000 of non-Hispanic white women (p < .05) between 1995 and 2002 NSFG cycles. The mean number of unwanted births had a tendency to increase across all socioeconomic groups between 1995 and 2002 and was the highest among young women from lower income families. Within each race/ethnicity category, there was a tendency toward an increase of the mean number of unwanted births among young women in almost every socioeconomic subgroup.
Table 4. Mean number of unwanted births in the past 5 years per 1,000 women aged 15–24 years, by race/ethnicity and poverty index, 1995 and 2002 NSFG surveys
| 1995 | 2002 | |||||
|---|---|---|---|---|---|---|
| N | Mean | 95% CI | N | Mean | 95% CI | |
| Total | 2,914 | 25 | 19–31 | 2,513 | 48b | 37–59 |
| Age | ||||||
| 1,396 | 11 | 6–17 | 1,150 | 17 | 10–23 | |
| 815 | 3 | 0.4–6 | 674 | 6 | 0.3–12 | |
| 581 | 23 | 11–36 | 476 | 32 | 17–48 | |
| 1,518 | 39 | 27–50 | 1,363 | 80b | 58–102 | |
| Race/ethnicityc | ||||||
| 1,688 | 14 | 8–21 | 1,388 | 28a | 18–37 | |
| 466 | 32 | 14–49 | 524 | 93b | 50–136 | |
| 643 | 72 | 45–99 | 460 | 90 | 58–121 | |
| Poverty index | ||||||
| 922 | 64 | 45–83 | 961 | 92 | 67–116 | |
| 1,044 | 12 | 6–19 | 760 | 27a | 14–41 | |
| 948 | 7 | 2–12 | 792 | 18 | 5–30 | |
| Race/ethnicity by poverty index (PI) | ||||||
| 375 | 40 | 15–65 | 416 | 60 | 31–88 | |
| 619 | 9 | 1–16 | 427 | 17 | 2–32 | |
| 694 | 6 | 1–10 | 545 | 12 | 1–23 | |
| 202 | 61 | 23–99 | 274 | 121 | 58–184 | |
| 168 | 14 | 0–30 | 161 | 73a | 25–120 | |
| 96 | 6 | 0–18 | 89 | 36 | 0–80 | |
| 314 | 120 | 72–168 | 211 | 143 | 93–193 | |
| 208 | 33 | 7–59 | 132 | 27 | 3–51 | |
| 121 | 27 | 0–55 | 117 | 55 | 0–113 | |
ap < .05. |
bp < .01. Comparison between the mean number of births per 1,000 women in 2002 NSFG cycle and the mean number of births per 1,000 women in 1995 NSFG cycle. |
cThe “other” race/ethnicity category includes <6% of women for each time period and is omitted. |
Discussion
Our analyses of several measures of pregnancy and childbearing intentions from the NSFG data suggest an increasing trend in unwanted childbearing among young women in the United States from 1990–1995 (based on 1995 NSFG cycle) to 1997–2002 (based on 2002 NSFG cycle). A larger proportion of women aged less than 25 years reported births that were unintended in 1997–2002 than in 1990–1995. Although the proportion of reported mistimed births remained stable, we found that the proportion of unwanted births nearly doubled among young women during this time period. A larger proportion of young nulliparous women who were interviewed in 2002 expressed no intention of having any births in the future than did those who were interviewed in 1995. Finally, the mean number of unwanted births reported by young women also increased during this time period. The increases in unwanted childbearing were not only evident across all race/ethnicity and socioeconomic groups, but also across all socioeconomic levels within each race/ethnicity category.
These findings must be considered in the context of what is known about reproductive intentions, sexual behaviors, and fertility of young women. For example, delays in sexual initiation and increased use of effective contraceptive methods among adolescents contributed to decreases in the rate of adolescent pregnancy and childbearing in the United States between 1990 and 2000 [1], [24]. This trend could partially account for the increase in the proportion of nulliparous women who reported that they wanted no future births: young women who wanted no births could have been more likely to avoid pregnancy during the period covered by the 2002 NSFG cycle than in the period covered by the previous cycle. The decreasing number of unintended pregnancies ending in abortions [2] may also partially explain the increased proportion of unwanted births among young women: women with unwanted pregnancies may have been more likely to give birth during the period covered by the 2002 NSFG cycle than during the 1995 cycle. Despite these possible explanations, evidence supports a residual or true trend of increased unwanted childbearing among young women, because the mean number of unwanted births (which takes into account all outcomes) also increased. Further investigation is needed to identify whether either explanation could account for the trends we observed or whether other reasons, such as shifting attitudes about parenting, account for these patterns. A variety of factors could influence young women's attitudes toward future births, including their current relationships, educational and occupational goals, and influences of family and community [25], [26], [27]. Regardless of the reasons and motivations, our findings show an increase in the mean number of unwanted births among young women that implies an increasing number of women and infants at risk for many adverse health outcomes associated with unwanted births.
Our findings are subject to some limitations. For example, our analyses of birth intentions among women who had births were based on retrospectively collected reproductive health histories reported by young women after they became pregnant and gave birth. To the extent that women's recall of the wantedness of their pregnancies may tend to become more positive as more time passes from conception to delivery and from delivery to the interview (i.e., more likely to say that they wanted to be pregnant) [12], [28], our analyses might underestimate the prevalence of unwanted childbearing among young women. However, it is likely that the increasing trend we observed should hold, because no changes in data collection methods occurred in 1995 and 2002. Another limitation is related to the meanings of childbearing intentions for young women and how these meanings change over time [27], [29], [30]. The measures of childbearing intentions were developed and used in the 1940s, 1950s, and 1960s to understand the fertility of older women, that is, women who were nearing the end of childbearing [31], [32]. Thus, the meaning of these measures for young women is not clear. However, even if a certain number of young women misunderstood or misinterpreted the question about birth wantedness, it is unlikely that the extent of misunderstanding changed significantly from one NSFG cycle to another.
Although more research is necessary to better understand the observed trends, a substantial number of young women continue to experience unwanted pregnancies and births. If applied to the U.S. population of women aged 15 to 24 years, approximately 1,418,000 unwanted births (95% CI 1,139,000-1,698,000) would have occurred in the 5 years before 2002 by women less than 25 years old, or approximately 283,600 unwanted births per year. In 2002, an estimated 1,952,000 women (95% CI 1,601,000–2,304,000) 15 to 24 years old were at risk for unwanted births because they were sexually active and intended no future births. These young women could benefit from interventions to help them use contraception correctly and consistently. Without such interventions, they and their children may experience negative health outcomes.
To deliver interventions that meet the needs of young women, we need more research to understand the reasons behind unwanted childbearing. If young women truly do not want children during their adolescent years, with their current partner, or at any time in the future, they need access to interventions to help them achieve their fertility intentions and desires. Some young women may need interventions that help them feel more in control of their lives in general and their sexual lives in particular. Others may need help clarifying their goals and values for their lives, so that they can form intentions about childbearing that reflect their goals and values. All young women may need better access to effective use of contraception.
References
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The findings and conclusions in this article are those of the authors and do not necessarily represent views of the Centers for Disease Control and Prevention.
PII: S1054-139X(08)00156-0
doi:10.1016/j.jadohealth.2008.02.013
© 2008 Society for Adolescent Medicine. Published by Elsevier Inc. All rights reserved.
