Measurements of hCG and PAPP-A in uncommon types of ectopic gestation

Seven out of 54 women with ectopic gestation had uncommon features such as extra-tubal implantation or multiple intratubal pregnancy. Depressed levels (< 10th centile) or apparent absence of circulating human chorionic gonadotrophin (hCG) and pregnancy-associated plasma protein A (PAPP-A) were seen respectively in 5 and 7 of 7 women studied. Normal levels of hCG were seen in two women, one with an abdominal and one with an angular pregnancy. These data suggest that the synthesis of placental proteins in ectopic pregnancies is independent of the site of implantation and the number of embryos. Measurements of maternal levels of the 2 placental proteins seem to be applicable as auxiliary diagnostic tests for ectopic pregnancy, regardless of the site of implantation.