The Impact of Abortion Underreporting on Pregnancy Data and Related Research

Abstract

Introduction The impact on research findings that use pregnancy data from surveys with underreported abortions is not well-established. We estimate the percent of all pregnancies missing from women’s self-reported pregnancy histories because of abortion underreporting. Methods We obtained abortion and fetal loss data from the 2006–2015 National Survey of Family Growth (NSFG), annual counts of births from US vital statistics, and external abortion counts from the Guttmacher Institute. We estimated the completeness of abortion reporting in the NSFG as compared to the external counts, the proportion of pregnancies resolving in abortion, and the proportion of pregnancies missing in the NSFG due to missing abortions. Each measure was examined overall and by age, race/ethnicity, union status, and survey period. Results Fewer than half of abortions (40%, 95% CI 36–44) that occurred in the five calendar years preceding respondents’ interviews were reported in the NSFG. In 2006–2015, 18% of pregnancies resolved in abortion, with significant variation across demographic groups. Nearly 11% of pregnancies (95% CI 10–11) were missing from the 2006–2015 NSFG due to abortion underreporting. The extent of missing pregnancies varied across demographic groups and was highest among Black women and unmarried women (18% each); differences reflect both the patterns of abortion underreporting and the share of pregnancies ending in abortion. Discussion Incomplete reporting of pregnancy remains a fundamental shortcoming to the study of US fertility-related experiences. Efforts to improve abortion reporting are needed to strengthen the quality of pregnancy data to support maternal, child, and reproductive health research.

Detecting underreporters of abortions and miscarriages in the national study of family growth, 2011–2015

“…About 7 percent of the women are assigned to the latent class of women who had had an abortion in the last five years and, among them, about 40 percent did not report having had an abortion in at least one mode. This level of underreporting is consistent with other research, though lower than the rates of underreporting found in comparisons to the Guttmacher Institute abortion providers census [ 4 , 5 ].…”

“…Similarly, Tourangeau and his colleagues used a sample that included women who were known to have had abortions and found that fewer than 75 percent of them reported ever having had an abortion and only about half reported an abortion during the period in which they were known to have had one [ 7 ]. The problem of underreporting of abortions is not limited to the NSFG; abortions are also underreported in other national surveys in the U.S., including the 1997 National Longitudinal Survey of Youth and the Add Health Study, and in other countries [ 5 , 8 – 11 ].…”

“…The second goal is to try to understand factors affecting underreporting behavior of respondents by identifying the characteristics of respondents most prone to underreport abortion and miscarriage. Earlier work [ 4 , 5 ] to characterize women underreporting abortion were conducted at the aggregate level and found that older women, married women, poorer women, college graduates, and Catholics are more likely to underreport abortions than their younger, unmarried, wealthier, less educated, and non-Catholic counterparts. We hope to replicate these findings and to extend them by using individual-level data and by examining additional characteristics of women associated with underreporting abortions.…”

Abortion Among Physicians

“…Our study limitations include a nonrepresentative sampling strategy, self-reported data, and social desirability bias common in abortion research. 5 Even so, it is striking that almost one in six medical students reported that either they or their partner had an abortion.…”

“…Our study limitations include a nonrepresentative sampling strategy, self-reported data, and social desirability bias common in abortion research. 5 Even so, it is striking that almost one in six medical students reported that either they or their partner had an abortion. Underscoring stressors of medical training, one physician whose partner had an abortion reflected that she, "had 2 abortions (while we were in training).…”