Expectant care (waiting) versus surgical treatment for miscarriage

Miscarriage is pregnancy failure before 14 weeks, which is common in early pregnancy. Such a loss in early pregnancy can affect a woman’s physical and mental health. Doctors often suggest surgery such as dilation and curettage (D and C) or vacuum aspiration to complete the process. Surgery might cause problems such as trauma, heavy bleeding, or infection. Expectant management means waiting for the miscarriage to finish on its own, and may involve bed rest, examination by ultrasound, and antibiotics. This review looked at whether expectant management works as well as surgery for miscarriage.

We searched for randomized trials that compared waiting versus surgery for miscarriage. In addition, we looked at reference lists to find trials. We also wrote to researchers to find more studies. Seven trials with 1521 women looked at waiting versus surgery for miscarriage. More women who waited for the miscarriage to complete on its own had tissue left in the womb. This was studied at two weeks and at six to eight weeks. More of these women needed surgery to complete the process. These women also had more days of bleeding. Some needed to be given blood, compared with none in the surgery group. Both groups had about the same numbers of infections. Results were mixed for pain. Mental health also seemed about the same for both treatment groups. Costs were lower for waiting than for surgery. Overall, no strong medical results argue for either approach. Information was limited on future pregnancy. One trial was large, while the others had small numbers of women. What the woman prefers should be the major concern. Drug treatment (such as with misoprostol and mifepristone) has added choices for women and their clinicians, and has been studied in other reviews.

Authors' conclusions: 

Expectant management led to a higher risk of incomplete miscarriage, need for unplanned (or additional) surgical emptying of the uterus, bleeding and need for transfusion. Risk of infection and psychological outcomes were similar for both groups. Costs were lower for expectant management. Given the lack of clear superiority of either approach, the woman's preference should be important in decision making. Pharmacological ('medical') management has added choices for women and their clinicians and has been examined in other reviews.

Read the full abstract...

Miscarriage is a common complication of early pregnancy that can have both medical and psychological consequences such as depression and anxiety. The need for routine surgical evacuation with miscarriage has been questioned because of potential complications such as cervical trauma, uterine perforation, hemorrhage, or infection.


To compare the safety and effectiveness of expectant management versus surgical treatment for early pregnancy failure.

Search strategy: 

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (9 February 2012), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2011, Issue 4 of 4), PubMed (2005 to 11 January 2012), POPLINE (inception to 11 January 2012), LILACS (2005 to 11 January 2012) and reference lists of retrieved studies.

Selection criteria: 

Randomized trials comparing expectant care and surgical treatment (vacuum aspiration or dilation and curettage) for miscarriage were eligible for inclusion.

Data collection and analysis: 

Two review authors assessed trial quality and extracted data. We contacted study authors for additional information. For dichotomous data, we calculated the Mantel-Haenszel risk ratio (RR) with 95% confidence interval (CI). For continuous data, we computed the mean difference (MD) and 95% CI. We entered additional data such as medians into 'Other data' tables.

Main results: 

We included seven trials with 1521 participants in this review. The expectant-care group was more likely to have an incomplete miscarriage by two weeks (RR 3.98; 95% CI 2.94 to 5.38) or by six to eight weeks (RR 2.56; 95% CI 1.15 to 5.69). The need for unplanned surgical treatment was greater for the expectant-care group (RR 7.35; 95% CI 5.04 to 10.72). The mean percentage needing surgical management in the expectant-care group was 28%, while 4% of the surgical-treatment group needed additional surgery. The expectant-care group had more days of bleeding (MD 1.59; 95% CI 0.74 to 2.45). Further, more of the expectant-care group needed transfusion (RR 6.45; 95% CI 1.21 to 34.42). The mean percentage needing blood transfusion was 1.4% for expectant care compared with none for surgical management. Results were mixed for pain. Diagnosis of infection was similar for the two groups (RR 0.63; 95% CI 0.36 to 1.12), as were results for various psychological outcomes. Pregnancy data were limited. Costs were lower for the expectant-care group (MD -499.10; 95% CI -613.04 to -385.16; in UK pounds sterling).