Young age and termination of pregnancy during the second trimester are risk factors for repeat second-trimester abortion

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GENERAL GYNECOLOGY

Young age and termination of pregnancy during the second trimester are risk factors for repeat second-trimester abortion Maarit J. Mentula, MD; Maarit Niinimäki, MD, PhD; Satu Suhonen, MD, PhD; Elina Hemminki, MD, PhD; Mika Gissler, MSocSc, PhD; Oskari Heikinheimo, MD, PhD OBJECTIVE: The objective of the study was to characterize women un-

dergoing a termination of pregnancy (TOP) during the second trimester and to evaluate the risk factors and timing of repeat TOP. STUDY DESIGN: This nationwide retrospective cohort study investigated 41,750 women who underwent TOP during the first (n ⫽ 39,850) or second (n ⫽ 1900) trimester in Finland in 2000-2005. The follow-up time was until repeat TOP or until Dec. 31, 2006.

peat second-trimester TOP (HR, 3.8; 95% CI, 2.9 –5.1), and repeat TOP after 16 weeks of gestation (HR, 5.0; 95% CI, 3.3–7.7). The other risk factor for these is young age (HR, 7.0, 95% CI, 5.3–9.3; and HR, 12.5; 95% CI, 3.1–50.4 for age ⬍20 years). CONCLUSION: Second-trimester TOP and young age are risk factors for

repeat second-trimester TOP. Special focus on these women might be effective in decreasing repeat abortions.

RESULTS: TOP during the second trimester increases the risk of repeat

TOP (hazard ratio [HR], 1.4; 95% confidence interval [CI], 1.3–1.6), re-

Key words: risk factor, second trimester, termination of pregnancy

Cite this article as: Mentula MJ, Niinimäki M, Suhonen S, et al. Young age and termination of pregnancy during the second trimester are risk factors for repeat second-trimester abortion. Am J Obstet Gynecol 2010;203:107.e1-7.

T

ermination of an unwanted pregnancy remains a very common gynecological procedure throughout the world despite the improvement in contraceptive choices during the last decades. Thus, induced abortion remains a challenge for health care and familyplanning services. In particular, late termination of pregnancy (TOP) is

From the Department of Obstetrics and Gynecology, Helsinki University Central Hospital (Drs Mentula and Heikinheimo), the City of Helsinki Health Care Centre Unit for Maternity and Child Health Care and Health Promotion (Dr Suhonen), and the National Institute for Health and Welfare (Drs Hemminki and Gissler), Helsinki, and the Department of Obstetrics and Gynecology, Oulu University Hospital, Oulu (Dr Niinimäki), Finland, and the Nordic School of Public Health, Gothenburg, Sweden (Dr Gissler). Received Oct. 15, 2009; revised Dec. 29, 2009; accepted March 1, 2010. Reprints: Oskari Heikinheimo, MD, PhD, Department of Obstetrics and Gynecology, Helsinki University Central Hospital, P.O. Box 610, 00029-HUS, Helsinki, Finland. [email protected]. 0002-9378/$36.00 © 2010 Mosby, Inc. All rights reserved. doi: 10.1016/j.ajog.2010.03.004

associated with an increased risk of complications.1 The risk of abortion-related complications increases with gestational weeks.2 Major complications during second-trimester abortion occur in less than 1-11% of abortions, depending on the site and type of procedure.3-5 The increased morbidity in second-trimester TOP is likely to be due to increased fetal and placental size, increased blood volume, and a distended uterus with decreased resistance. Thus, various guidelines recommend that TOP should be performed as early as possible.6,7 The incidence of TOP varies greatly from country to country, being 9 of 1000 women of fertile age (15-49 years) in Finland,8 17 of 1000 in Sweden,9 20 of 1000 in the United States,10 and 18 of 1000 in England and Wales11 in 2007. The rate of late TOP, performed between gestational weeks 13 and 24 of pregnancy or even later, varies between 5% and 10%.8-11 Moreover, the rate of repeat TOP ranges from 30% to 47% in the countries mentioned in the earlier text.8-11 Risk factors associated with repeat TOP have been characterized in several studies. Prior abortion, young age, being parous, smoking, and postponement of

initiation of postabortal contraceptive use are related to increased risk.12-15 Also, a history of physical or sexual abuse is associated with repeat induced abortion.13 However, the method of induced abortion (medical vs surgical) in firsttrimester TOP is not a risk factor of repeat TOP.16 However, these data12-15 are mainly derived from studies performed on first-trimester TOP. The characteristics and risk factors of repeat later TOP may differ from these.13-17 The aim of this study was to assess the background as well as the risk and timing of a repeat TOP in women undergoing their first TOP during the second trimester (ie, gestational weeks 12 plus 1 to 24 plus 0) in comparison with women undergoing their first TOP during the first trimester of pregnancy (ie, ⬍12 plus 1 gestational weeks).

M ATERIALS AND M ETHODS As shown in Figure 1, the study cohort consisted of 42,955 women who underwent their first termination of pregnancy between Jan. 1, 2000, and Dec. 31, 2005, according to The Finnish Register of Induced Abortions and Sterilizations.8 Only women not having concurrent sterilization at the time of abortion were included in the study. In addition,

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FIGURE 1

Flowchart of women undergoing their first TOP

The flowchart of the 42,955 women undergoing their first termination of pregnancy from Jan. 1, 2000, to Dec. 31, 2005. TOP, termination of pregnancy. Mentula. Second-trimester TOP and risk factors of repeat abortion. Am J Obstet Gynecol 2010.

women undergoing TOP because of fetal abnormality were excluded because the timing of TOP in these cases is based mainly on fetal diagnosis, thus representing a different entity. This left a total of 41,750 women for further analyses. The cohort was divided into 2 groups according to the number of gestational weeks at the time of the first TOP. First trimester was defined as duration of gestation 84 days or less (ie, ⱕ12 plus 0 weeks). Second trimester was defined as duration of gestation between 85 and 168 days (ie, weeks 12 plus 1 to 24 plus 0). This division derives from the Finnish legislation on induced abortion, which divides pregnancies into first and second trimester using the duration of pregnancy of 84 days as a division point. 107.e2

The follow-up time was until first repeat TOP or until Dec. 31, 2006. All women were followed up for at least 1 year. Deaths (n ⫽ 99; 0.002% after firsttrimester primary TOP and n ⫽ 12; 0.004% after second-trimester primary TOP) in the cohort were not taken into account in calculations of the follow-up time, nor was possible emigration to other countries. To be considered as a repeat TOP, the time interval between the index TOP and the repeat TOP was compared with the reported gestational weeks at the time of repeat TOP. This was done because the Finnish legislation requires a new application and a new announcement for a TOP if the first attempted TOP is unsuccessful and the pregnancy continues into the second trimester. Therefore, ongoing

American Journal of Obstetrics & Gynecology AUGUST 2010

pregnancies after a failed first-trimester abortion were not mistakenly considered as repeat abortions. The effects of background factors such as socioeconomic status (SES) and type of residence were also evaluated. The former was defined by using the stated occupation or the highest educational level found in the Abortion Register.8 Coding was based on national standards published by Statistics Finland.18-20 SES was divided into 5 categories: upper white-collar workers, lower whitecollar workers, blue-collar workers, students (level of education not defined), and others. The type of residence was defined by using data on the municipality of residence, available in the Abortion Register.8 The municipalities were divided into 3 categories: urban, densely

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www.AJOG.org populated, or rural areas, according to national standards. According to the current law on induced abortions in Finland, TOP can be allowed up to 20 plus 0 weeks of gestation (24 plus 0 weeks in cases of a medical condition of the fetus). An approval with a legal indication for termination of pregnancy is needed, although the legislation is interpreted liberally. Legal indications for the TOP include social, ethical, and medical reasons. Medical reasons include maternal health issues (ie, a pregnancy being a risk to the woman’s health or life, woman’s sickness, or physical defect or infirmity etc) or other reasons that neither the mother nor the father are able to take care of the child. Medical reasons also include proven or suspected fetal issues (ie, mental deficiency, severe illness, or handicap of the fetus). Ethical and social reasons are the pregnancy or child care being a considerable stress on living or other conditions; age below 17 or 40 years or older at the time of conception; or 4 or more previous deliveries; or rape, incest, or other reasons mentioned in the penal law. Finnish legislation on induced abortion can be found at www.finlex.fi.21 This study had an approval of the Finnish Ministry of Social Affairs and Health (STM/1690/2006).

Research

TABLE 1

The characteristics of women (n ⴝ 41,750) undergoing first TOP in Finland between 2000 and 2005 Characteristic

First trimester (n ⴝ 39,850)

Second trimester (n ⴝ 1900)

Difference percent (95% CI)

P value

Age, y

.....................................................................................................................................................................................................................................

⬍20

12076 (30.3)

880 (46.3)

–16.0 (–18.3 to –13.7)

⬍ .001

20-24

10934 (27.4)

499 (26.3)

1.2 (–0.9 to 3.2)

25-29

6694 (16.8)

190 (10.0)

6.8 (5.3–8.1)

⬍ .001

30-34

4920 (12.3)

155 (8.2)

4.2 (2.8–5.4)

⬍ .001

35-39

3644 (9.1)

120 (6.3)

2.8 (1.6–3.9)

⬍ .001

ⱖ40

1582 (4.0)

56 (2.9)

1.0 (0.1–1.7)

.....................................................................................................................................................................................................................................

.26

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................

.02

..............................................................................................................................................................................................................................................

Deliveries

.....................................................................................................................................................................................................................................

0

25239 (63.3)

1399 (73.6)

–10.3 (–12.3 to –8.2)

1

5901 (14.8)

244 (12.8)

2.0 (0.3–3.4)

ⱖ2

8710 (21.9)

257 (13.5)

8.3 (6.7–9.9)

⬍ .001

.....................................................................................................................................................................................................................................

.02

.....................................................................................................................................................................................................................................

⬍ .001

..............................................................................................................................................................................................................................................

History of miscarriage

.....................................................................................................................................................................................................................................

0

35722 (89.6)

1743 (91.7)

1

3281 (8.2)

126 (6.6)

847 (2.1)

31 (1.6)

–2.1 (–3.3 to –0.7)

.003

.....................................................................................................................................................................................................................................

1.6 (0.4–2.7)

.01

0.5 (–0.2 to 1.0)

.14

.....................................................................................................................................................................................................................................

ⱖ2

..............................................................................................................................................................................................................................................

Type of residence

.....................................................................................................................................................................................................................................

Urban

4.6 (2.5–6.7)

⬍ .001

29048 (72.9)

1298 (68.3)

Densely populated

5446 (13.7)

295 (15.5)

–1.9 (–3.6 to –0.3)

⬍ .001

Rural

5356 (13.4)

307 (16.2)

–2.7 (–4.5 to –1.1)

⬍ .001

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................

Marital status

.....................................................................................................................................................................................................................................

Single

26955 (67.6)

1431 (75.3)

–7.7 (–9.6 to –5.6)

Cohabiting

6155 (15.4)

298 (15.7)

–0.2 (–2.0 to 1.4)

Married

6740 (16.9)

171 (9.0)

–2.8 (–4.2 to 1.6)

⬍ .001

.....................................................................................................................................................................................................................................

.78

.....................................................................................................................................................................................................................................

⬍ .001

..............................................................................................................................................................................................................................................

Statistical analysis Statistical analyses were performed using PASW 18.0 for Mac (SPSS Inc, Chicago, IL). Confidence intervals for the differences between independent proportions were calculated by using interval estimation for differences.22 Time to repeat TOP was analyzed with survival methods (Kaplan-Meier) and their statistical significance with log rank tests (MantelCox). Risk factors of repeat TOP were analyzed by using Cox regression models. Estimated risks were presented as hazard ratios (HRs) with 95% confidence intervals (CIs). Variables that showed a statistically significant association (P ⬍ .05) with repeat TOP in univariable analysis were entered in multivariable analysis. Forward conditional Cox regression model was used.

Socioeconomic status

.....................................................................................................................................................................................................................................

Upper white-collar

2469 (6.2)

51 (2.7)

3.5 (2.7–4.2)

⬍ .001

Lower white-collar

7572 (19.0)

224 (11.8)

7.2 (5.6–8.6)

⬍ .001

Blue-collar workers

5240 (13.1)

253 (13.3)

–0.2 (–1.8 to 1.3)

..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................

.83

.....................................................................................................................................................................................................................................

Students

15629 (39.2)

762 (40.1)

–0.9 (–3.2 to 1.3)

.44

Others

2699 (6.8)

117 (6.2)

0.6 (–0.6 to 1.6)

.30

Not known

6241 (15.7)

493 (25.9)

–10.3 (–12.3 to –8.3)

..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................

⬍ .001

..............................................................................................................................................................................................................................................

Indication

.....................................................................................................................................................................................................................................

Considerable stress

34762 (87.2)

1456 (76.6)

3670 (9.2)

353 (18.6)

10.6 (8.7–12.6)

⬍ .001

–9.4 (–11.2 to –7.7)

⬍ .001

.....................................................................................................................................................................................................................................

Age ⬍17 years

.....................................................................................................................................................................................................................................

Rape

20 (⬍0.1)

1 (⬍0.1)

0 (–0.2 to 0)

.96

0.6 (–0.1 to 1.1)

.10

.....................................................................................................................................................................................................................................

Age ⱖ40 years

923 (2.3)

33 (1.7)

.....................................................................................................................................................................................................................................

ⱖ4 deliveries

355 (0.9)

19 (1.0)

–0.1 (–0.7 to 1.1)

Maternal health

120 (0.3)

38 (2.0)

–1.7 (–2.4 to –1.2)

.62

.....................................................................................................................................................................................................................................

⬍ .001

..............................................................................................................................................................................................................................................

The data are shown as n (percent) unless stated otherwise. CI, confidence interval; TOP, termination of pregnancy. Mentula. Second-trimester TOP and risk factors of repeat abortion. Am J Obstet Gynecol 2010.

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TABLE 2

The risk factors of repeat TOP following primary induced abortion during the first or second trimester

Risk factor

First-trimester index TOP HR (95% CI) for repeat TOP

P value

Second-trimester index TOP HR (95% CI) for repeat TOP

P value

Age at primary TOP, y

.....................................................................................................................................................................................................................................

⬍20

6.84 (5.11–9.16)

⬍ .001

12.00 (1.68–85.63)

.01

20-24

5.80 (4.33–7.77)

⬍ .001

12.16 (1.70–87.12)

.01

25-29

4.61 (3.42–6.20)

⬍ .001

7.61 (1.04–56.03)

⬍ .05

30-34

3.24 (2.40–4.39)

⬍ .001

8.07 (1.09–59.68)

⬍ .05

35-39

2.12 (1.54–2.91)

⬍ .001

6.74 (0.89–51.04)

.07

ⱖ40

Reference

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................

Reference

..............................................................................................................................................................................................................................................

Previous deliveries

.....................................................................................................................................................................................................................................

0

Reference

Reference

1

1.29 (1.20–1.38)

⬍ .001

1.55 (1.19–2.03)

⬍ .01

ⱖ2

0.83 (0.78–0.89)

⬍ .001

0.82 (0.58–1.15)

.25

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................

Previous miscarriages

.....................................................................................................................................................................................................................................

0

Reference

Reference

1

1.16 (1.06–1.27)

⬍ .01

0.95 (0.62–1.46)

.82

ⱖ2

0.95 (0.79–1.15)

.61

0.69 (0.26–1.86)

.47

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................

Type of residence

.....................................................................................................................................................................................................................................

Urban

Reference

Reference

Densely populated

0.96 (0.89–1.04)

.28

0.78 (0.57–1.05)

.1

Rural

0.87 (0.81–0.95)

.01

0.76 (0.56–1.02)

.07

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................

Marital status

.....................................................................................................................................................................................................................................

Married

Reference

Reference

Cohabiting

1.52 (1.37–1.68)

⬍ .001

0.97 (0.60–1.55)

.23

Single

1.59 (1.47–1.73)

⬍ .001

1.27 (0.86–1.87)

.89

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................

Socioeconomic status

.....................................................................................................................................................................................................................................

Upper white collar

Reference

Reference

Lower white collar

1.30 (1.12–1.51)

⬍ .01

1.26 (0.53–3.01)

.60

Blue-collar workers

2.03 (1.74–2.36)

⬍ .001

1.80 (0.78–4.19)

.17

Students

2.03 (1.76–2.34)

⬍ .001

2.05 (0.92–4.64)

.08

Others

2.59 (2.21–3.04)

⬍ .001

1.95 (0.80–4.73)

.14

Not known

1.38 (1.18–1.61)

⬍ .001

1.29 (0.56–2.97)

.55

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................

Indication for primary TOP

.....................................................................................................................................................................................................................................

Considerable stress

Reference

Reference

Age ⬍17 years

1.26 (1.16–1.36)

⬍ .001

1.09 (0.85–1.40)

.50

Other

0.33 (0.26–0.42)

⬍ .001

0.58 (0.31–1.08)

.09

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................

CI, confidence interval; HR, hazard ratio; TOP, termination of pregnancy. Mentula. Second-trimester TOP and risk factors of repeat abortion. Am J Obstet Gynecol 2010.

107.e4

American Journal of Obstetrics & Gynecology AUGUST 2010

First terminations of pregnancy were performed less often during the second trimester (7% vs 93%). In this cohort first-trimester TOP was performed either medically or surgically, but the majority (86.3%) of second-trimester TOP was performed medically, using a combination of mifepristone and misoprostol. Only 12.5% of second-trimester terminations were performed surgically. The durations of pregnancy (mean ⫾ SD) at the time of TOP were 8.2 (⫾1.7) and 15.7 (⫾2.1) gestational weeks in the cohorts of first- and second-trimester primary TOP, respectively. The annual frequency of second-trimester first TOP in this cohort varied from 6.7% to 7.5% during 2000-2005. The follow-up times (mean ⫾ SD) were 47.8 ⫾ 20.8 and 47.0 ⫾ 20.7 months following first- and second-trimester index TOP, respectively. The characteristics of the 2 cohorts are shown in Table 1. The mean (⫾SD) ages of the women undergoing first TOP during the first and second trimesters were 24.7 (⫾7.3) and 22.2 (⫾7.0) years, respectively (P ⬍ .001). Repeat TOP occurred more often after a first TOP performed during the second trimester than after a first TOP during the first trimester (19.2% vs 13.9%; P ⬍ .001) (Figure 1). Furthermore, following the second-trimester first TOP, the repeat TOP was performed more often during the second trimester (15.3% vs 5.7%; P ⬍ .001). Also, the risk of repeat TOP performed after 16 weeks of gestation was higher following a second-trimester first TOP than following a firsttrimester first TOP (HR, 5.03; 95% CI, 3.31–7.65; P ⬍ .001). The timing of a repeat TOP was also of interest. The time to repeat TOP was shorter if the repeat TOP occurred in the second trimester than in the first trimester (mean, 1.40 years; 95% CI, 1.25–1.54 vs 1.57 years; 95% CI, 1.53–1.61; P ⬍ .001). Furthermore, a repeat second-trimester TOP occurred earlier following a second-trimester than following a firsttrimester TOP (mean, 1.07 years; 95% CI, 0.75–1.39 vs 1.46 years; 95% CI, 1.30 –1.61, respectively; P ⫽ .03).

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TABLE 3

The risk factors of repeat TOP and repeat TOP performed during the second trimester Risk factor

HR (95% CI) for repeat TOP

P value

HR (95% CI) for 2nd trimester repeat TOP

P value

Trimester at primary TOP

.....................................................................................................................................................................................................................................

First

Reference

Second

1.43 (1.29–1.59)

Reference

.....................................................................................................................................................................................................................................

⬍ .001

3.84 (2.89–5.10)

⬍ .001

..............................................................................................................................................................................................................................................

Age at primary TOP, y

.....................................................................................................................................................................................................................................

⬍20

7.00 (5.25–9.34)

⬍ .001

12.52 (3.11–50.44)

⬍ .001

20-24

5.96 (4.46–7.97)

⬍ .001

8.53 (2.11–34.54)

.003

25-29

4.67 (3.48–6.26)

⬍ .001

4.71 (1.14–19.52)

.03

30-34

3.34 (2.48–4.51)

⬍ .001

3.85 (0.91–16.30)

.07

35-39

2.21 (1.62–3.03)

⬍ .001

2.40 (0.53–10.81)

.26

⬎40

Reference

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................

Reference

..............................................................................................................................................................................................................................................

Previous deliveries

.....................................................................................................................................................................................................................................

0

Reference

1

1.30 (1.21–1.39)

⬍ .001

Reference

1.11 (0.84–1.46)

.47

ⱖ2

0.82 (0.77–0.88)

⬍ .001

0.60 (0.44–0.81)

.001

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................

Previous miscarriages

.....................................................................................................................................................................................................................................

0

Reference

1

1.14 (1.04–1.25)

.004

Reference

0.84 (0.56–1.26)

.84

ⱖ2

0.93 (0.78–1.13)

.47

1.03 (0.51–2.07)

.94

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................

Research

The risk factors associated with repeat TOP were also evaluated. As shown in Table 2, the risk factors were mainly similar following the first- and second-trimester first TOP. Young age and history of a delivery increased the risk of repeat TOP significantly in both cohorts. We then carried out univariable analysis on the risk factors of repeat TOP, with a separate analysis of repeat TOP performed during the second trimester (Table 3). The risk factors for repeat TOP during the second trimester were first TOP during the second trimester, young age, at least 2 previous deliveries, not being married, being from a lower socioeconomic class or a student, and the indication for the first TOP being age under 17 years. These risk factors were further entered into a multivariable analysis in which we compared the risk factors associated with repeat TOP and repeat TOP during the second trimester. In these analyses an increased risk of repeat second-trimester TOP remained significantly associated with previous TOP during the second trimester, young age, and previous deliveries (Figure 2).

Type of residence

.....................................................................................................................................................................................................................................

Urban

Reference

Densely populated

0.95 (0.88–1.02)

.18

Reference

1.05 (0.78–1.41)

.73

Rural

0.87 (0.81–0.94)

.001

1.09 (0.82–1.46)

.56

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................

Marital status

.....................................................................................................................................................................................................................................

Married

Reference

Cohabiting

1.50 (1.35–1.66)

⬍ .001

Reference

1.95 (1.24–3.05)

.004

Single

1.60 (1.47–1.73)

⬍ .001

2.43 (1.67–3.54)

⬍ .001

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................

Socioeconomic status

.....................................................................................................................................................................................................................................

Upper white collar

Reference

Lower white collar

1.32 (1.12–1.51)

.001

Reference

1.20 (0.64–2.28)

.57

Blue-collar workers

2.04 (1.76–2.36)

⬍ .001

1.77 (0.94–3.35)

.08

Students

2.06 (1.79–2.36)

⬍ .001

2.57 (1.43–4.61)

.002

Others

2.58 (2.20–3.02)

⬍ .001

2.51 (1.29–4.88)

.007

Not known

1.41 (1.21–1.64)

⬍ .001

1.91 (1.02–3.57)

.04

..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................

Indication for primary TOP

.....................................................................................................................................................................................................................................

Considerable stress

Reference

Reference

Age ⬍17 years

1.26 (1.17–1.36)

⬍ .001

1.90 (1.45–2.48)

Other

0.35 (0.28–0.44)

⬍ .001

0.30 (0.11–0.80)

.....................................................................................................................................................................................................................................

⬍ .001

.....................................................................................................................................................................................................................................

.02

..............................................................................................................................................................................................................................................

The univariable analysis of women (n ⫽ 41,750) undergoing primary TOP in Finland during 2000-2005. CI, confidence interval; HR, hazard ratio; TOP, termination of pregnancy. Mentula. Second-trimester TOP and risk factors of repeat abortion. Am J Obstet Gynecol 2010.

C OMMENT A minority of primary terminations of pregnancy are performed during the second trimester. However, in the present study, we found that a second-trimester TOP is an independent risk factor not only of a repeat TOP but also for repeat TOP during the second trimester and a repeat TOP in later pregnancy (ie, after 16 weeks of gestation). The present study is the first in which second-trimester abortion and the risk factors of repeat TOP following that have been specifically assessed. The strengths of the study are the large nationwide, population-based database and excellent coverage of the Finnish Register of Induced Abortions and Sterilizations.8,23 This register contains data on all induced abortions and sterilizations performed in Finland since 1977. Its coverage approaches 100%8,23 because it is based on physicians’ obligatory and law-based reports from the hospitals in which induced abortions are carried out. These

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General Gynecology

FIGURE 2

Multivariable analysis of the risk factors of second trimester repeat TOP

The reference categories are indicated. TOP, termination of pregnancy. Mentula. Second-trimester TOP and risk factors of repeat abortion. Am J Obstet Gynecol 2010.

reports are completed at the time of abortion. This study cannot answer the question of whether different procedures (surgical vs medical) to perform second-trimester TOP have an effect on repeat TOP. Nordic countries have a long tradition of using predominantly medical methods for second-trimester induced abortion.8 This is also recommended in the Finnish guidelines for induced abortion.6 However, the method of induced abortion is not a risk factor for repeat TOP during first trimester.16 The characteristics between the 2 groups, primary TOP during the first or second trimester, differed slightly but significantly in several respects, namely that women undergoing second-trimester TOP were younger, had fewer pregnancies, and were more often single than women undergoing their first TOP during the first trimester. The risk factors associated with repeat TOP were mainly similar following firstand second-trimester first TOP. The risk factors of young age, previous childbirth, not being married, and being of a lower socioeconomic class are similar to those previously reported after first-trimester 107.e6

TOP.12-17,24 However, the role of previous TOP performed during the second trimester is a novel finding. This study does not provide specific information of the reasons that these women underwent TOP during the second trimester, some of them repeatedly. Finnish legislation on induced abortions demands that TOP should be performed without any unnecessary delays once the woman has decided to apply for TOP. Also, nearly all of the induced abortions were performed in public hospitals. Therefore, it can be assumed that costs or availability of services do not have an important effect on the timing of the TOP. We speculate that the risk groups identified in the present study represent in part women who are displaced or have additional problems in life, resulting in second-trimester TOP. Factors affecting the timing of repeat abortion are poorly known. In the present study, we found that following the second-trimester TOP, the repeat TOP and the repeat second-trimester TOP also occurred earlier than after the first-trimester TOP. Thus, the study has practical implications. Clearly, women undergoing in-

American Journal of Obstetrics & Gynecology AUGUST 2010

www.AJOG.org duced abortion during the second trimester need special attention, especially those who are younger than 20 years of age. The efficacy of specialized contraceptive services in prevention of repeat abortion has been questioned.25-27 Because second-trimester TOP is a difficult procedure associated with an increased risk of complications, it is tempting to speculate that provision of additional contraceptive services might be cost effective from the standpoint of the service provider and also serves the women concerned. Thus, various strategies to reduce the need of repeat TOP must be studied further. Unfortunately, even intensive contraceptive counseling at the time of abortion has not been shown to be effective in reducing the rates of repeat TOP.25-27 However, postabortal use of intrauterine contraception has decreased the need of repeat TOP.12 Therefore, easy access to contraceptive services, low-cost or free contraception, and immediate initiation of long-acting reversible methods of contraception might be beneficial among the risk groups identified in the present study. In conclusion, the second-trimester TOP significantly increased the risk of a repeat TOP and a repeat second-trimester TOP. This repeat second-trimester TOP also occurs earlier. Special focus and service provision to the risk groups identified might decrease the rate of repeat abortions in these women. f REFERENCES 1. Grossman D, Blanchard K, Blumenthal P. Complications after second trimester surgical and medical abortion. Reprod Health Matters 2008;16(Suppl):173-82. 2. Ferris LE, McMain-Klein M, Colodny N, Fellows G F, Lamont J. Factors associated with immediate abortion complications. Can Med Assoc J 1996;154:1677-85. 3. Buehler JW, Schulz KF, Grimes DA, Hogue CJ. The risk of serious complications from induced abortion: do personal characteristics make a difference? Am J Obstet Gynecol 1985;153:14-20. 4. Turok DK, Gurtcheff SE, Esplin MS, et al. Second trimester termination of pregnancy: a review by site and procedure type. Contraception 2008;77:155-61. 5. Autry A, Hayes E, Jacobson G, Kirby R. Comparison of medical induction and dilation

www.AJOG.org and evacuation for second-trimester abortion. Am J Obstet Gynecol 2002;187:393-7. 6. Finnish Medical Society Duodecim. The Finnish Current Care guidelines. April 9, 2007 Abortion. Available at: http://www.kaypahoito.fi/. Accessed Sept. 2, 2009. 7. Royal College of Obstetricians and Gynaecologists (RCOG). The care of women requesting induced abortion. London (UK): Royal College of Obstetricians and Gynaecologists (RCOG). September 2004. 104 pages (evidence-based clinical guideline; number 7). 8. Statistics 2007. Available at: http://www. stakes.fi/EN/tilastot/statisticsbytopic/reproduc tion/abortionsandsterilisations.htm, Accessed Sept. 2, 2009. 9. Statistics 2007. Available at: http://www. socialstyrelsen.se Accessed Sept. 2, 2009. 10. Statistics 2007. Available at: http://www. guttmacher.org/sections/abortion.php. Accessed Sept. 2, 2009. 11. Statistics 2007. Available at: http://www. dh.gov.uk Accessed Sept. 2, 2009. 12. Heikinheimo O, Gissler M, Suhonen S. Age, parity, history of abortion and contraceptive choices affect the risk of repeat abortion. Contraception 2008;78:149-54. 13. Prager SW, Steinauer JE, Greene Foster D , Darney PD, Drey EA. Risk factors for repeat

General Gynecology elective abortion. Am J Obstet Gynecol 2007; 197:575.e1-6. 14. St John H, Critchley H, Glasier A. Can we identify women at risk for more than one termination of pregnancy? Contraception 2005;71: 31-4. 15. Fisher WA, Singh SS, Shuper PA. Characteristics of women undergoing repeat induced abortion. CMAJ 2005;172:637-41. 16. Niinimäki M, Pouta A, Bloigu A, et al. Frequency and risk factors for repeat abortions after surgical compared with medical termination of pregnancy. Obstet Gynecol 2009;113: 845-52. 17. Drey EA, Foster DG, Jackson RA, Lee SJ, Cardenas LH, Darney PD. Risk factors associated with presenting for abortion in the second trimester. Obstet Gynecol 2006;107:128-35. 18. Statistics Finland. Classification of occupations. Handbooks 14. Helsinki, Finland: Statistics Finland; 1987. 19. Statistics Finland. Classification of socioeconomic groups. Handbooks 17. Helsinki, Finland: Statistics Finland; 1989. 20. Statistics Finland. Classification of education, Dec. 31, 1991. Handbooks 1. Helsinki, Finland: Statistics Finland; 1992. 21. Finnish legislation on induced abortion. Available at: http://www.finlex.fi/fi/laki/ajantasa/1970/

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19700239?search%5Btype%5D⫽pika&search %5Bpika%5D⫽raskau%2A. Accessed Sept. 2, 2009. 22. Newcombe RG. Interval estimation for the difference between independent proportions: comparison of eleven methods. Stat Med 1998;17:873-90. 23. Gissler M, Ulander V-M, Hemminki E, Rasimus A. Declining induced abortion rate in Finland: data quality of the Finnish Abortion Register. Int J Epidemiol 1996;25:376-80. 24. Heikinheimo O, Gissler M, Suhonen S. Can the outcome of the next pregnancy be predicted at the time of induced abortion? Hum Reprod 2008; 23: 1-7. 25. Bender S, Geirsson R. Effectiveness of preabortion counseling on postabortal contraceptive use. Contraception 2004;69:481-7. 26. Moos M, Bartholomew N, Lohr K. Counseling in the clinical setting to prevent unintended pregnancy: an evidence-based research agenda. Contraception 2003;67:115-32. 27. Schunmann C, Glasier A. Specialist contraceptive counseling and provision after termination of pregnancy improves uptake of long-acting methods but does not prevent repeat abortion: a randomized trial. Hum Reprod 2006;21:2296-303.

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