Endometriosis and pregnancy outcome: are pregnancies complicated by endometriosis a high-risk group?

Increased incidence of preterm birth, pregnancy-induced hypertension (PIH) and small-for-gestational-age (SGA) babies have been reported in women with endometriosis, but the study populations included women in whom a definitive diagnosis was not attainable, and women who conceived via in vitro fertilization/embryo transfer (IVF/ET), which, in itself, is a risk factor for adverse pregnancy outcome. Thus there is a lack of consensus on the effects of endometriosis on pregnancy outcome. This study compared the pregnancy outcomes of women with or without a definitive diagnosis of endometriosis on laparoscopy.

Retrospective comparison of pregnancy outcomes of 108 women who underwent managed delivery of pregnancies established after laparoscopic investigation of infertility. Women with factors known to affect pregnancy outcome, such as age ≥41 years, conception via IVF/ET and multiple births, were excluded. Forty-nine of the study participants had endometriosis (En+ group) and 59 participants did not have endometriosis (En- group).

There were no significant differences in mean (±standard deviation) age (33±3.8 vs 33.6±4.1 years), history of miscarriage, history of preterm birth and history of PIH between the two groups. Ovulation induction was used for infertility treatment in 26.5% of the En+ group and 30.5% of the En- group, and artificial insemination was used in 30.6% of the En+ group and 32.2% of the En- group. Regarding pregnancy outcomes, no significant differences in miscarriage (18.4% vs 18.6%), subchorionic haematoma (5.0% vs 2.1%), preterm birth (7.5% vs 8.3%), PIH (15.0% vs 12.5%), caesarean section (32.5% vs 22.9%), gestational age at delivery (38.9±1.5 vs 38.8±1.7 weeks), birth weight (3013.3±480 vs 2934.5±639.5g) and SGA babies (2.5% vs 2.1%) were found between the En+ and En- groups. Placental abruption did not occur in either group. One neonate had trisomy 21 in the En+ group, and one woman had gestational diabetes in the En- group.

Endometriosis may not affect pregnancy outcome, but there is a need for a large prospective study.