Introduction: Doppler sonography of maternal vessels as a predictor for preeclampsia is an established screening method in the second trimester. Considering the first trimester its benefit has not been conclusively proven so far. Up to now the flow pattern of maternal vessels in the first trimester has only been insufficiently characterized and documented. Thus, there are only few pieces of information concerning the predictive value of the different kinds of flow patterns during the early pregnancy as regards the pathological and physiological outcome of the pregnancy. This survey aimed at evaluating the significance and the clinical importance of Doppler sonographical examinations of the Aa. uterinae during early pregnancy. It had to be analyzed whether various perfusions can be applied as a predictive value for the specific development during the pregnancy and whether therefore a risk group for pregnancy-associated hypertension can already be detected during the early pregnancy.
Materials and methods: A non-selected collective of 104 pregnant patients was examined with Doppler sonography and retrospectively divided into a standard collective and a high-risk collective. The standard collective contained 89 patients, who in the course of their pregnancy remained without any pathological findings. Fifteen patients, who were assigned to the high-risk collective, either developed a pregnancy-induced hypertension during their pregnancy or an intrauterine fetal growth retardation. The Doppler-sonographic examination of the Aa. uterinae was applied for the first time between the 6 and 8 weeks gestation (WG), then in the 9 WG, 10 WG, 11 WG, between the 12 and 14 WG, as well as between the 20 and 24 WG.
Results: Contrary to published data, there can be traced a completely transformed flow pattern in the Aa. uterinae already during the first trimester to an increasing extent. This correlates with a positive outcome of the pregnancy. There is a definite association between pathological Doppler sonography in the first third of the pregnancy and the development of a uteroplacental insufficiency as well as a pregnancy-associated hypertension (SIH) in the further course of the pregnancy.
Conclusion: Doppler sonography is an approved method in order to become early attentive of a reduced uterine blood flow. Applying Doppler sonographic treatment of the maternal vessels, uteroplacental insufficiency can be traced at an early stage. Pregnancies, which might develop a pregnancy-associated hypertension (SIH) or a placental insufficiency, can be detected during the early pregnancy to decrease the morbidity rate and the mortality of premature newborns. Further studies in larger collectives are necessary to obtain adequate solid datasets and to further evaluate the clinical meaning and the significance concerning pathological maternal Doppler parameters.