Patients with diffuse adenomyosis compared with those with endometriosis only had significantly lower pregnancy-associated plasma protein A (0.61 vs 0.88 multiple of the median, P < 0.001), higher mean uterine artery pulsatility index in the first (2.23 vs 1.67, P < 0.001) and second (1.30 vs 0.94, P < 0.001) trimesters of pregnancy, and higher incidence of SGA (40% vs 10.8%, P < 0.001).