Risky Sexual Behaviors and Repeat Induced Abortion Among Unmarried Young Women in China: Results from a Large,Nationwide,Population-Based Sample

Abstract

Background:

Young women are disadvantaged with respect to their ability to access contraception, which puts them at especially high risk of repeat induced abortion. This study aims to estimate the prevalence of repeat induced abortion and to identify its association with risky sexual behaviors among unmarried young women in China.

Materials and Methods:

Data were obtained from the Survey of Youth Access to Reproductive Health in China and collected using probability proportionate to size sampling. Population numbers and prevalence of repeat induced abortion by characteristics were calculated among 11,076 unmarried young women aged 15–24 years. Univariate logistic regression, multivariate logistic regression, and logistic regression with propensity score-based weighting were used to elucidate the associations of each risky sexual behavior with repeat induced abortion among sexually active young women.

Results:

The prevalence of repeat induced abortion was 0.8% (95% confidence interval [CI]: 0.7–1.0) among unmarried young women (11,076) and it accounted for 21.3% of those who had ever had induced abortion. Among sexually active young women, the prevalence of abortion was 4.40% (95% CI: 3.6–5.4). Condom nonuse during the first sexual experience (odds ratio = 2.72, 95% CI: 1.55–4.76), sexual activity with multiple partners (9.71, 5.61–16.81), being forced to have sexual intercourse (4.46, 1.44–13.76), casual sex (5.77, 3.28–10.13), commercial sex (4.51, 2.01–10.12), condom nonuse during the most recent sexual encounter (2.01, 1.31–3.08), and having any of the above behaviors (5.68, 2.26–14.28) were associated with repeat abortion.

Conclusions:

Risky sexual behaviors were associated with repeat abortion among unmarried young women in China. The findings highlight the need for reproductive health promotion programs for unmarried young women in China and other similar settings.

Introduction

Repeat induced abortion remains an increasing concern in the international community, especially for developing countries.¹ Whereas one abortion is indicative of unintended pregnancy, repeat abortion might signify the larger problem of unintended pregnancy.² Women having a repeat abortion may be perceived as having difficulty practicing contraception, or as using abortion as a method of family planning, who are badly in need of support from family planning service programs.³ In many cases, young women are disadvantaged with respect to their ability to access contraception, which puts them at especially high risk of repeat induced abortion.¹ In the United States, more than half of all abortions were by women in their twenties with youth aged 20–24 accounting for 33% of all abortions.⁴ Previous studies indicated that about 16%–41% of women seeking an abortion reported to have had repeat induced abortion in Africa, Asia, and northern Europe.^5

–10

By reviewing previous studies, a number of themes became apparent as the determinant factors for repeat abortion, including (i) sociodemographic factors, such as increased age,^11,12 lower education level,⁷ being students,¹³ living in a middle-developed region or a relatively poor region¹⁴; (ii) individual or risky behaviors, such as living alone,¹² living in rented accommodation,¹¹ have left school at an earlier age,¹¹ smoking,^8,9 and drinking¹⁵; (iii) psychosocial factors, such as adverse life events¹⁶; (iv) obstetric history, such as more prior births³; and (v) sexual knowledge and behaviors, such as lack of knowledge or access to usage of contraceptive methods,⁷ early debut of sexual behavior,¹¹ a greater number of sexual partners,¹¹ and sexual abuse or violence.¹²

As the most populous nation, China has an estimated number of more than 175 million youth aged 15–24 years, accounting for 12.8% of the total population.¹⁷ In China, premarital sex and unwanted pregnancy became more and more prevalent among unmarried young women.^18,19 As a result, induced abortions are always taken as a negative remedy to unintended pregnancies, which does great harm to the physical and mental health of young people in their subsequent life.²⁰

However, studies on repeat abortion among Chinese young women are relatively rare and all are hospital-based. Three local studies suggested that 32.1%–38.5% of unmarried young women seeking an abortion in Beijing, Changsha, and Shanghai in China reported having repeat induced abortion.^21
–23 A study conducted in 30 provinces in China reported 39% of adolescents (13–19 years) seeking abortions within 12 weeks of pregnancy were undergoing repeat abortions.¹⁴ These studies indicated that subjects who had children resided in a middle-developed or relatively poor region, nonstudents with multiple sexual partners, unwanted sex, and contraceptive failure were indicated more likely to have repeat abortions.^14,21
–23 However, these studies used data with small sample size or hospital-based samples and provided little information about individual participants or sex-related information, and thus the exploration of the association between risky sexual behaviors and repeat abortion among Chinese young women was not well attempted.

In this study, we aimed to estimate the prevalence rate of repeat induced abortion and identify the association between risky sexual behaviors with repeat induced abortion among Chinese unmarried young women aged 15–24 using nationally representative data. The findings may inform future strategies to enhance reproductive healthcare service for the young people.

Materials and Methods

Data and study samples

Data were obtained from the Survey of Youth Access to Reproductive Health in China, conducted by Institute of Population Research, Peking University from October 20 to November 30, 2009. The objective of this survey is to describe the knowledge, attitude and behavior of sexual and reproductive health among youth and to explore the accessibility to reproductive health services for youth in China.²⁴ The target population of this survey was Chinese unmarried youth aged 15–24 years including school youth (i.e., youth in school, either living on campus or commuting), household youth (i.e., youth living at home with their family, either employed or unemployed), and collective household youth (i.e., employed young people living in a communal house), living in mainland China.

Four stages stratified random cluster sampling with probability proportional to size was used to get the probabilistic samples. The four stages were cities, schools/counties, classes/communities/map pieces (divided according to streets, rivers, and so on in the map), and school youth/household youth/collective household youth. The final estimated sample size was 22,535, with a sampling ratio of 11.4 per 100,000. Given the refusal rate of 24.9%, when the selected subject was unable to contact, or there was no youth aged 15–24 in the selected household, we followed the samples substitution principle in which the neighbor of nonrespondents would be taken as the replacement with a swing priority from right to left within 5 U. Finally, 22,465 questionnaires in paper–pencil version were collected, among which 22,288 were valid after excluding cases with the wild, extreme, or missing values, and values with logic errors, that is, a valid rate of 98.9%. There is no significant demographic difference between the deleted cases and samples for analysis. In this study, only female respondents were considered. Thus, the samples were restricted to 11,076 young women cases, and a subgroup of sexually active young women (N = 2,114) was selected for further association study. More details of the sample selection were shown in Figure 1.

FIG. 1.

Flowchart of the study samples.

Ethical approval

The study protocol of this survey was reviewed and approved by the Institutional Review Board of Peking University Health Science Centre. All respondents gave their consent to participate in the survey; the consents were signed by their adult guardians for the respondents aged under 18 years. During the survey, necessary measures were taken to protect the privacy of the participants: (i) The participants were interviewed face to face in independent environments without the third party present; (ii) The name and contact information of interviewees were not required; (iii) All sensitive questions related to sexual experiences and behaviors in the questionnaire were self-administered and completed by participants themselves; (iv) All questionnaires were collected in ballot boxes after being completed; (v) Interviewees were interviewed by interviewers of the same sex.

Measures

Demographic and socioeconomic information

The delimitation of the age range in this survey was according to the United Nations definition of “youth” referring to all those between the ages of 15 and 24.²⁵ Age at the time of the survey was set as continuous and further categorized as 15–19 years of age and 20–24 years of age. Survey respondents were also categorized by residence location (rural areas or urban areas), province region (east, central, or west), mother's education level (primary school and above, junior and senior high school, or college and above), living with parents (yes or no), annual family income per capita (categorized by terciles: “top” for above 15,000 yuan, “middle” for 7,500–15,000 yuan, and “bottom” for under 7,500 yuan), cigarette use (yes or no, based on the response to the question “Have you ever used cigarette?”), and alcohol use (yes or no, based on the response to the question “Have you ever used alcohol?”).

Induced abortion and repeat induced abortion

In this survey, induced abortion referred to an intentional termination of any pregnancy before the fetus has developed enough to live if born.²⁶ Abortion was identified if one responded “Yes” to the question “Have you ever had an induced abortion during the pregnancy you have experienced (if any)?” (classified as yes or no). Based on the number of induced abortions, abortion twice and above for any pregnancy (latest or previous) was further identified as repeat induced abortion and classified as yes or no.

Risky sexual behaviors

Sexually active young women were identified if one responded affirmatively to the question “Have you ever had a sexual experience (whether it was with your current/latest girlfriend/boyfriend or with any others)?” In this survey risky sexual behaviors among the sexually active participants included “condom nonuse during the first sexual experience” (yes or no), “sexual activity with multiple partners” (yes or no), “being forced to have sexual intercourse (yes or no), “taking part in casual sex” (yes or no), “commercial sex” (yes or no), and “condom nonuse during the most recent sexual encounter” (yes or no). We further defined “any risky sexual behaviors” as any of the six behaviors listed earlier and categorized it as binary (yes or no).

Statistical analysis

All data were entered into a customized database and analyzed using STATA 13 (STATA Corp., College Station, TX). Descriptive statistics were used to present the sample characteristics, population numbers, and prevalence and proportion of repeat induced abortion by various sociodemographic characteristics among all the samples. Chi square tests were used to determine the difference within categorical variables. For the aim to identify the associations between risky sexual behaviors and repeat abortions, a subgroup of sexually active young women was selected and analyzed by three kinds of logistic regression models. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated in each model. We set p-value <0.05 as statistically significant.

We used univariate logistic regression to elucidate the associations of each risky sexual behavior with repeat induced abortion, without controlling other confounders. Then, multivariate logistic regression was used to calculate the adjusted associations, with controlling demographic, individual, and social variables including age, residence, region, living with parents, mother's education, smoking, drinking, and family income based on the reports of previous studies. Furthermore, we also conducted the logistic regression with propensity score-based weighting, which offers greater confidence that risky sexual behavior effect estimates derived from observational data are unbiased to elucidate the associations between each risky sexual behavior and repeat induced abortion among the sexually active youth.

In logistic regression with propensity score-based weighting, we used logistic regression to predict each risky sexual behavior conditional on baseline demographic and socioeconomic characteristics and estimated the propensity score. Then, we gave each individual an inverse probability of treatment weight based on an actual risky sexual behavior.^27,28 The weights for those with the behavior and without the behavior equaled to the inverse of the estimated propensity score (1/propensity score), and the inverse of 1 minus the estimated propensity score (1/1 − propensity score), respectively.²⁷ This weighting scheme ensures that balance is achieved between the with and without risky sexual behavior groups on baseline characteristics,²⁹ and it offers greater confidence that risky sexual behavior effect estimates derived from observational data are unbiased.^27,29,30

Results

Characteristics of samples

The analysis samples comprised 11,076 unmarried young women at 15–24 years of age. The average age of samples was 18.9 ± 2.5 years and 60.8% were under 20 years of age. Demographically, 43.7% of the participants were living in rural areas. Study population characteristics are presented in Table 1.

Table 1.

Participant Characteristics and Prevalence of Repeat Induced Abortion Among Chinese Unmarried Young Women (N = 11,076)

Characteristics	Samples		Repeat induced abortion
Characteristics	No.	Proportion (%)	No.	Prevalence (%) with 95% CI	p
Total	11,076	100.0	93	0.8 (0.7–1.0)
Age group (years)					<0.001
15–19	6,731	60.8	28	0.4 (0.3–0.6)
20–24	4,345	39.2	65	1.5 (1.1–1.9)
Residence location					0.049
Rural	4,837	43.7	50	1.0 (0.8–1.4)
Urban	6,239	56.3	43	0.7 (0.5–0.9)
Region					0.001
East	6,117	55.2	36	0.6 (0.4–0.8)
Central	2,762	24.9	25	0.9 (0.6–1.3)
West	2,197	19.8	32	1.5 (1.0–2.1)
Cigarette use					<0.001
Yes	679	6.1	31	4.6 (3.1–6.4)
No	10,397	93.9	62	0.6 (4.6–7.6)
Alcohol use					<0.001
Yes	2,698	24.4	52	1.9 (1.4–2.5)
No	8,378	75.6	41	0.5 (0.4–0.7)
Living with parents					0.001
Yes	10,407	94.0	80	0.8 (0.6–1.0)
No	669	6.0	13	1.9 (1.0–3.3)
Mother's education					0.025
Primary school and above	2,587	23.4	25	1.2 (0.8–1.7)
Junior and senior high school	7,239	65.4	55	0.8 (0.6–1.0)
College and above	1,250	11.3	6	0.5 (0.2–1.0)
Annual family income per capita (RMB Yuan)					0.934
Top	3,836	34.6	31	0.8 (0.5–1.1)
Middle	3,503	31.6	31	0.9 (0.6–1.3)
Bottom	3,737	33.7	31	0.8 (0.6–1.2)

CI, confidence interval.

Prevalence of repeat induced abortion among unmarried young women

A total of 436 persons had ever had induced abortion, accounting for 3.9% of the total participants (11,076). Among them 93 (21.3%) reported repeat induced abortion. The prevalence of repeat induced abortion was 0.8% (95% CI: 0.7–1.0) among unmarried young women. We calculated the prevalence of repeat induced abortion demographically and socioeconomically. A higher prevalence was found among young women at 20–24 years of age (p < 0.001), living in rural areas (p = 0.049), residing in central or west region (p < 0.001), not living with parents (p = 0.001), with low mother's education (p = 0.025), with cigarette use (p < 0.001), and with alcohol use (p < 0.001) (Table 1). In multivariable logistic regression models, increased age (OR = 1.28, 95% CI: 1.17–1.40), living in the west region (2.35, 1.42–3.89), not living with parents (1.89, 1.00–3.56), cigarette use (4.61, 2.72–7.81), and alcohol use (1.80, 1.10–2.96) were significant (Appendix Table A1).

Association between risky sexual behaviors and repeat induced abortion among sexually active young women

The analysis samples for the association study included 2,114 sexually active young women. Among them, the prevalence of repeat abortion was 4.40% (95% CI: 3.6–5.4). The young women with any risky sexual behavior reported a significant higher proportion of repeat abortion (5.48%) compared with those without risky sexual behavior (0.98%) (p < 0.001). The trend is same in each specific type of risky sexual behavior (Table 2).

Table 2.

Risky Sexual Behaviors and Repeat Induced Abortion Among Sexually Experienced Young Women (N = 2,114)

Risky sexual behaviors	Sexually experienced young women		Proportion of repeat induced abortion
Risky sexual behaviors	No.	Proportion (%)	No.	%	p
Condom nonuse during the first sexual experience
No	742	35.10	15	2.02	<0.001
Yes	1,372	64.90	78	5.69
Sexual activity with multiple partners
No	1,789	84.63	42	2.35	<0.001
Yes	325	15.37	51	15.69
Forced sex
No	2,072	98.01	86	4.15	<0.001
Yes	42	1.99	7	16.67
Casual sex
No	1,901	89.92	60	3.16	<0.001
Yes	213	10.08	33	15.49
Commercial sex
No	1,983	93.80	77	3.88	<0.001
Yes	131	6.20	16	12.21
Condom nonuse during the most recent sexual encounter
No	1,457	68.92	49	3.36	0.001
Yes	657	31.08	44	6.70
Any behavior above
No	509	24.08	5	0.98	<0.001
Yes	1,605	75.92	88	5.48

Moreover, after adjusting the demographic and socioeconomic variables and weighting based on propensity score, those with condom nonuse during the first sexual experience (OR = 2.72, 95% CI: 1.55–4.76), having sexual activity with multiple partners (9.71, 5.61–16.81), being forced to have sexual intercourse (4.46, 1.44–13.76), taking part in casual sex (5.77, 3.28–10.13), having commercial sex (4.51, 2.01–10.12), condom nonuse during the most recent sexual encounter (2.01, 1.31–3.08), and having any of the above risky sexual behaviors (5.68, 2.26–14.28) were more likely to have repeat abortion compared to their counterparts (Table 3). The ORs and CIs of the control variables were presented in Appendix Table A2.

Table 3.

The Association Between Risky Sexual Behaviors and Repeat Induced Abortion Among Sexually Experienced Young Women (N = 2,114)

Risky sexual behaviors	Univariate logistic regression			Multivariate logistic regression ^a			Logistic regression with propensity score-based weighting ^a
Risky sexual behaviors	OR	95% CI	p	OR	95% CI	p	OR	95% CI	p
Condom nonuse during the first sexual experience (Reference = No)
Yes	2.92	1.67–5.11	<0.001	2.74	1.56–4.83	<0.001	2.72	1.55–4.76	<0.001
Sexual activity with multiple partners (Reference = No)
Yes	7.74	5.05–11.88	<0.001	7.65	4.85–12.08	<0.001	9.71	5.61–16.81	<0.001
Forced sex (Reference = No)
Yes	4.62	1.99–10.70	<0.001	3.93	1.63–9.46	0.005	4.46	1.44–13.76	0.009
Casual sex (Reference = No)
Yes	5.63	3.58–8.84	<0.001	5.79	3.51–9.55	<0.001	5.77	3.28–10.13	<0.001
Commercial sex (Reference = No)
Yes	3.44	1.95–6.09	<0.001	3.32	1.77–6.22	0.001	4.51	2.01–10.12	<0.001
Condom nonuse during the most recent sexual encounter (Reference = No)
Yes	2.06	1.36–3.13	0.001	2.00	1.31–3.07	0.001	2.01	1.31–3.08	0.001
Any behavior above (Reference = No)
Yes	5.85	2.36–14.48	<0.001	5.45	2.19–13.55	<0.001	5.68	2.26–14.28	<0.001

Regressions were adjusted for demographic and socioeconomic variables including age, residence location, region, mother's education level, living with parents, and annual family income per capita, smoking, drinking.

OR, odds ratio.

Discussion

This study described the population-based prevalence of repeat induced abortion among unmarried young women in China for the first time. The results indicated that 0.8% of unmarried young women reported repeat induced abortion. Unfortunately, there is no previous population-based prevalence report about repeat abortion among youth at this age range in China, which makes it is difficult to compare our results within China. According to our study, 21.3% (93/436) of those who have ever had an induced abortion in our study have reported repeat induced abortion, which is a little lower than the previous reports among unmarried young women seeking an abortion (32.1%–39%).^14,21
–23 This could be due to the different study populations used in various studies. Data used in our study were from a large, nationwide, population-based sample and the findings were more nationally representative for China. Given the large population of China, repeat induced abortion among young women is still an important health issue for China.

There is growing awareness that unmarried young women are facing enormous reproductive challenges around the world. The theme of World Population Day in 2013 is “adolescent pregnancy”.³¹ Actually, given that unmarried birth is against the family planning law and will be imposed a fine in China, unmarried Chinese girls could be more disadvantaged on abortion matters compared with married women in China and their counterparts in some other countries. In addition, the unbalanced access to contraceptive services between married and unmarried women including information, education, and provision of contraceptive methods is still notable, since most of the sexual and reproductive health services are focusing on married couples.³² The burden of child-rearing, barriers to contraceptive services, and social discrimination especially for unmarried women highlight the need of potential policy change focusing on young girls.

This study also reported the prevalence of repeat induced abortion by demographic and social characteristics. The unmarried young women living in the west region were associated with higher prevalence of repeat induced abortion. This could be explained by the unbalanced distribution of health resources across China, where most of the west regions (less developed than the east regions) had fewer reproductive health resources including contraceptive services and sex education for adolescents and youth.^33,34 Furthermore, we find that not living with parents were associated with higher prevalence of repeat induced abortion. Previous studies also indicated the significant role of family support in adolescents' reproductive well-being.^35,36 The family relatives, especially the mother may provide important sources to support the adolescents' decision making including repeat induced abortion.³⁷ In addition, higher prevalence of repeat abortion is found among the unmarried young women who had ever used cigarette or alcohol. This is consistent with previous studies that indicated cigarette and alcohol use were associated with unprotected sex, unwanted pregnancies, induced abortions and repeat induced abortion.^20,27,38 This relationship is especially strong for young people, for their knowledge and skills are still being developed and their sexual behaviors are necessary to be regulated in adaptive ways.^15,38

Moreover, according to our findings, among the sexually active young women, those who have ever had risky sexual behaviors were more likely to have repeat abortions. In our study, a total of six common sexual behaviors were included. Condom nonuse, sexual activity with multiple partners, and forced sex had been analyzed in the previous studies in Nepal, Britain, Canada, and China,^7,11,12,22 which are consistent with our finding. Casual sex and commercial sex were additionally reported by our research, which adds new data to the existing literature. Thus, by any measure, the main emphasis to reduce repeat abortion is the prevention of risky sexual behaviors and unwanted pregnancies with socioeconomic factors being taking into account. Integrating postabortion family planning services including contraception provision after an abortion would also be helpful in China as it has been effective to decrease unintended pregnancy and repeat abortions.³⁹ Currently, China is undergoing medical system reform and a “Healthy China Plan” has been developed by the government as a national strategy, in which youth and women are two of the key populations. Our findings will be beneficial for implementing more comprehensive reproductive health strategies for improving the well-being of young women, especially the unmarried ones.

The current study has several limitations. First, induced abortions remain a very sensitive topic among young Chinese, and thus we met a refusal rate of 24.9% in the survey. Although the samples have been replaced by the neighbor of nonrespondents based on the samples substitution principle, there might be an underestimation in our prevalence result because of the abortion stigma and challenges in information disclosure. Second, some other unobserved but important factors would be associated with repeat abortions, such as early debut of sexual behaviors, lack of knowledge or access to usage of other contraceptive methods, especially emergency methods were not included in our study, which may result in an overestimation in the association results in this study. Third, for the cross-sectional design of the survey, our findings cannot provide direct evidence of causality and should be interpreted with caution, while the use of logistic regression with propensity score-based weighting offers a greater confidence in the relation between risky sexual behavior and repeat induced abortion. Additionally, the data we used focused on unmarried young women and life time abortion, so the sexual behaviors of women after marriage and abortion by gestation age could not be observed. With regard to social and sexual behavior changes occurring relatively quickly in China, nationwide population-based survey should be conducted to explore the reproductive health conditions and verify our findings. Regardless of its limitations, given the fact that the study was based on a large, representative population-based sample covering all mainland areas of China, this study provides a new and broader understanding of risky sexual behaviors and repeat induced abortion among unmarried youth in China.

Conclusions

This study presented the prevalence of repeat induced abortion and its relationship to risky sexual behaviors among Chinese unmarried youth. The findings highlight the reproductive challenges of young women in China and indicate the need for reproductive health promotion programs including services and education improvement for young women in China and other similar settings.

Footnotes

Acknowledgments

This work was supported by the Changjiang Scholar Incentive Program and the China Postdoctoral Science Foundation (Grant No. 2018M630009).

Author Disclosure Statement

No competing financial interests exist.

Appendix Table A2. Multivariate Logistic Regression for Demographic, Social, and Behavior Factors Associated with Repeat Induced Abortion Among Sexually Experienced Young Women (N = 2,114)

Characteristics	Repeat induced abortion
Characteristics	OR	95% CI	p
Age	0.98	0.89–1.08	0.735
Residence location			0.018
Rural	Reference
Urban	0.57	0.35–0.91
Region
East	Reference		0.010
Central	1.54	0.90–2.63
West	1.94	1.16–3.25
Mother's education			0.613
Primary school and above	Reference
Junior and senior high school	0.96	0.59–1.58
College and above	0.71	0.27–1.85
Living with parents			0.221
Yes	Reference
No	1.50	0.78–2.87
Annual family income per capita (RMB Yuan)			0.916
Bottom	Reference
Middle	0.93	0.54–1.60
Top	0.98	0.55–1.75
Cigarette use			<0.001
No	Reference
Yes	2.59	1.53–4.37
Alcohol use			0.610
No	Reference
Yes	1.14	0.69–1.86

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