Endometriosis and impaired placentation: a prospective cohort study
comparing uterine arteries Doppler pulsatility index in pregnancies of
patients with and without moderate-severe disease
Abstract
Objective: To evaluate if moderate-severe endometriosis impairs uterine
arteries pulsatility index (UtA-PI) during pregnancy when compared to
unaffected controls. Design: Observational prospective cohort study.
Setting: University-affiliated obstetrics and fetal medicine Department
in Italy. Population: Pregnant women with stage III-IV endometriosis
according to revised American Fertility Society (r-AFS) classification,
matched in a 1:2 ratio according with body mass index and parity with
unaffected controls. Methods: UtA-PIs were assessed at 11–14, 19–22
and 26–34 weeks of gestation following major reference guidelines. A
General Linear Model (GLM) was implemented to evaluate the association
between endometriosis and UtA-PI Z-scores. Main Outcome Measure: UtA-PI
Z-scores, calculated from published reference equations of previously
validated normal range. Results: Significantly higher third trimester
UtA-PI Z-scores were observed in patients with r-AFS stage III-IV
endometriosis when compared to controls (p=0.024). In the GLM,
endometriosis (p=0.026) and maternal age (p=0.007) were associated with
increased third trimester UtA-PI Z-scores, whereas conception by
in-vitro fertilization with frozen-thawed embryo transfer significantly
decreased UtA-PI measures (p=0.011). No differences were observed in
first or in second trimester UtA-PI Z-scores of cases vs. controls.
Conclusions: Stage III-IV endometriosis according to r-AFS
classification is associated with a clinically measurable impaired
placental perfusion as shown by increased UtA-PI Z-scores in the third,
but not in the first or second trimesters. Closer follow-up may be
recommended in pregnant patients affected by moderate-severe
endometriosis in order to attempt prediction and prevention of adverse
pregnancy/perinatal outcomes due to a defective late placental
perfusion. Funding: N/A.