Endometriosis and spontaneous abortion rate: a cohort study in infertile women.

OBJECTIVE

To ascertain if there is an association between endometriosis and spontaneous abortion.

DESIGN

Prospective cohort study.

SETTING

Medical School Hospital.

POPULATION

174 infertile women laparoscopically diagnosed with endometriosis and 174 infertile women in which endometriosis was ruled out by laparoscopy, in the same period of time.

MAIN OUTCOME MEASURE

Spontaneous abortion. Non-progressive gestational sac and/or histological study.

RESULTS

Per woman abortion rate was 7.47% (13/174) in the endometriosis group, similar to 5.74% (10/174) in the infertile women without endometriosis (RR=1.32: CI=0.53-3.36). Nor were there any differences in the per pregnancy abortion rate: 20.96% (13/62) in endometriosis vs. 16.94% (10/59) in non-endometriosis (RR=1.3; CI=0.47-3.57). The abortion rate was similar in the different AFS stages: 22.86% (8/35) in stage I, 16.67% (3/18) in II, 25% (1/4) in III and 20% (1/5) in IV. In stage I no differences were observed in patients who were managed expectantly or with medical treatment.

CONCLUSION

Endometriosis is not associated with an increased abortion rate. The severity of disease expressed by AFS staging is not associated with an increase in the abortion rate. In stage I the treatment of endometriosis did not decrease abortion rates.