Use of plasma adrenomedullin could help predict tubal ectopic pregnancy

Based on data from an in vitro study on oviductal tissue, researchers at the University of Hong Kong found that plasma adrenomedullin levels could predict tubal ectopic pregnancy.

At the start of the study, researchers hypothesized that adrenomedullin (ADM), when altered, could play a role in the pathogenesis of tubal ectopic pregnancy (TEP).

“This is the first report to address the effect of ADM on cilia beat frequency and muscular contraction in the oviduct,” study researcher Wai-Sum O, PhD, of the University of Hong Kong, said in a press release. “We found that low ADM expression may contribute to slower muscle contraction and ciliary beating, which hampers embryo transport and favors embryo retention in the oviduct. This finding is significant because plasma ADM levels may be useful in predicting TEP.”

Isthmic parts of oviducts were collected from women undergoing hysterectomy for benign gynecologic conditions (aged 50 ± 2.2 years) and women undergoing salpingectomy for TEP (aged 32.1 ± 3.9 years) at Queen Mary Hospital in Hong Kong, researchers wrote. Additionally, the oviductal tissues were incubated in hormonal conditions, mimicking early pregnancy before they were used for in vitro analyses.

Results showed that ciliary beat frequency and frequency of muscle contraction were lower in oviducts of patients with TEP than that of patients with simulated pregnancies (P<.001), and the plasma and oviductal tissue ADM levels were also lower.

“In all, we report for the first time a significantly reduced expression of ADM in human oviductal tissue in TEP compared with control. ADM increases ciliary motility, smooth muscle tone, and contraction frequency, and the reduced ADM level in the TEP may contribute to its pathogenesis by impairing embryo transport,” the researchers concluded.

Disclosure: The researchers report no relevant financial disclosures.