Later Abortion Initiative

A project of Ibis Reproductive Health

The safety of later abortion

Later abortion is a safe and effective procedure. The following complications of later abortion have been reported, although rates for these have been very low (less than 5%):

Retained products of conception — Retained products of conception are found following fewer than 1% of second trimester D&E procedures [1,2].
Uterine perforation — Uterine perforation is potentially one of the most serious complications of surgical abortion and occurs in fewer than 1% of second trimester D&E procedures [3,4]. Factors that increase the risk of uterine perforation include: increasing gestational age, cervical abnormalities, multiparity, and an inexperienced provider. Perforations in the second trimester are more likely to involve injury to bowel or other structures than those occurring in the first trimester [5,6].
Cervical laceration — A cervical laceration occurs in up to 3% of second trimester abortions, whether performed by D&E or medical abortion [7]. Surgeons can reduce the frequency of cervical laceration by using cervical preparation and mechanical dilators. Most cervical lacerations are small and require no intervention.
Infection — Infection rates following second trimester abortion vary up to 4%. Definitions and diagnostic criteria of postabortion infection also vary [3-5]. Use of prophylactic antibiotics reduces rates of infection to less than 1% [8].
Hemorrhage — Definitions of postabortion hemorrhage vary. Although many investigators have previously defined hemorrhage as an estimated blood loss of ≥200 mL, the Society of Family Planning definition is either ≥500 mL or a surrogate marker (eg, need for transfusion) [9]. Estimates of the incidence of postabortion hemorrhage vary: rates reported range from 0 to 3 cases/1000 first trimester procedures versus 0.9 to 10/1000 cases of second trimester abortion [7]. There are no data regarding the rates of hemorrhage in surgical compared with induction termination. However, blood loss is higher in induction procedures [9-11]. Hemorrhage can result from a variety of causes, including uterine atony, retained products of conception, coagulopathy, abnormal placentation, and uterine or cervical injury. Uterine atony is the most common cause of hemorrhage following D&E, occurring in approximately 2% of D&E procedures [12].
Mortality — From 2004 to 2008, the United States Centers for Disease Control and Prevention (CDC) reported a mortality rate of 0.64 per 100,000 legal induced abortions; these data are for first and second trimester and the majority of abortions were D&E procedures [13].
Effect on subsequent pregnancy — Data regarding D&E risks to subsequent pregnancy vary. In a retrospective review of 600 patients undergoing D&E between 14 and 24 weeks, the overall rate of preterm birth in subsequent pregnancies was less than the overall rate of preterm birth for the general United States population (6.5 versus 12.5%) [14]. Similarly, a study that compared subsequent pregnancy outcomes among 317 women undergoing second trimester D&E with 170 matched controls found that women with a history of prior D&E delivered slightly earlier in gestation than controls (38.9 versus 39.5 weeks of gestation); this was statistically significant, but clinical significance is uncertain. There was no statistically significant difference in birth weight, spontaneous preterm delivery, abnormal placentation, and overall rates of perinatal complications [15].

[Adapted from Hammond, C. Second trimester pregnancy termination. In: UpToDate, Steinauer, J (Ed), UpToDate, Waltham, MA. (Accessed on August 26, 2015.)]

References

1. Bryant AG, Grimes DA, Garrett JM, Stuart GS. Second-trimester abortion for fetal anomalies or fetal death: labor induction compared with dilation and evacuation. Obstet Gynecol 2011; 117:788

2. Whitley KA, Trinchere K, Prutsman W, et al. Midtrimester dilation and evacuation versus prostaglandin induction: a comparison of composite outcomes. Am J Obstet Gynecol 2011; 205:386.e1

3. Peterson WF, Berry FN, Grace MR, Gulbranson CL. Second-trimester abortion by dilatation and evacuation: an analysis of 11,747 cases. Obstet Gynecol 1983; 62:185

4. Jacot FR, Poulin C, Bilodeau AP, et al. A five-year experience with second-trimester induced abortions: no increase in complication rate as compared to the first trimester. Am J Obstet Gynecol 1993; 168:633

5. Grimes DA, Schulz KF, Cates WJ Jr. Prevention of uterine perforation during curettage abortion. JAMA 1984; 251:2108

6. Pridmore BR, Chambers DG. Uterine perforation during surgical abortion: a review of diagnosis, management and prevention. Aust N Z J Obstet Gynaecol 1999; 39:349

7. Pridmore BR, Chambers DG. Uterine perforation during surgical abortion: a review of diagnosis, management and prevention. Aust N Z J Obstet Gynaecol 1999; 39:349

8. Altman AM, Stubblefield PG, Schlam JF, et al. Midtrimester abortion with Laminaria and vacuum evacuation on a teaching service. J Reprod Med 1985; 30:601

9. Sawaya GF, Grady D, Kerlikowske K, Grimes DA. Antibiotics at the time of induced abortion: the case for universal prophylaxis based on a meta-analysis. Obstet Gynecol 1996; 87:884

10. Kerns J, Steinauer J. Management of postabortion hemorrhage: release date November 2012 SFP Guideline #20131. Contraception 2013; 87:331

11. Niinimäki M, Suhonen S, Mentula M, et al. Comparison of rates of adverse events in adolescent and adult women undergoing medical abortion: population register based study. BMJ 2011; 342:d2111