Studies On Prediction Of Preterm Delivery Using Changed In Serum Relaxin And Ultrasonogrophic Measurement Of Cervical Length

Premature birth is one of the most common causes of perinatal death in thenewborn. For many years, the obstetricians from every contury dedicate themselves tostudy the happening of Prematature birth, and tailor the treatment.Humans and other higher primates have three relaxin genes, of which the 6-kdapeptide hormone H2 Relaxin(relaxin-2) is the predominant in the circulation andproduced in the corpus luteum during pregnancy. Recant years, some foreignresearches think that the increasing serum relaxin can speed up the ripening, andcause premature birth. In order to make a study of the relationship between serumrelaxin and premature birth, we use a standard ELISA to measure serum relaxin levelof pregnants, meanwhile many studies consider that it is a high rate to forecast thespecificity of premature birth and negative predictive value by ultrasonographicmeasurement of cervical length. This essay, the author determines the cervicalripenning by the method of ultrasonographic measurement of cervical length, andprobes into the prediction of preterm delivery by the prediction of preterm deliveryusing changed in Serum Relaxin and ultrasonogrophic measurement of cervical length.Also the author studies on the remission after treating the pregnants who are havingpremature birth, and the serum relaxin's changes of the period of before and after thetreatment and premature birth. Then have a further study on the regulation of thechanges of serum relaxin of the pregnants.This research has the following:Studies on prediction of preterm delivery using changed in serum relaxin andultrasonographic measurement of cervical length. This research applies a standardELISA to measure the density of serum relaxin of the pregnants, and then usesALOCK diagnostic ultrasonoscope produced by Japan, which contains ultrasonicprobe P118 in it. Its frequency is 5MHz. It measures the length of cervical and discusses the level of pregnants' serum relaxin and ultrasonographic measurement ofcervical length to predict the premature birth by using ultrasonographicmeasurement of cervical length, meanwhile, studies on the changing level of serumrelaxin of premonitory symptom of premature birth after treating. This study taketheir serum individually at the moment they are in hospital and seven days aftertreatment. At last, the author analyses the the difference of serum relaxin between theperiod of before and after treatment, further, studies on the difference of serum relaxinlevel in the period of before and after premature birth. This research takes their serumindividually at the moment they are in hospital and three days after giving birth. Thenthe author analyses the changing of serum relaxin before and after giving birth.The main results of this essay are the following1. This study uses unit element and multiple elements logistic regression,from table 1 to table 7. The results show that the portent premature birthpeople associate with the contracions, preterm prelabour rupture ofmenbranes, ripe cervices, serum relaxin (s-relaxin), (P＜0.01). The uteruscontraction was associated with increased risk of preterm deliveryOR:8.714(95%ci:1.255-60.492); the serum relaxin rising raised the risk ofpreterm delivery OR: 1.223(95%CI: 1.056-1.417). In the analysis of simpleand multivariate regression, the uterus shrink raised s-relaxin wasassociated with increased risk of preterm deliveryOR:6.5(95%CI:3.088-13.683); preterm prelabour rupture of menbraneswas associater with the risk of preterm deliveryOR: 1.078(95%CI: 1.047-1.111). The weeks of pregnancy, as one of thevariate, increased the risk of preterm birth OR:0.893-0.935. During thestudy, according to the relationship between the level of prgenants' serumrelaxin and the weeks of pregnancy, we designed the ROC curve fromreceivrer operating characteristic, and determined the level of serumrelaxin at 13ng/ml as the cut off. When s-relaxin above 13ng/ml, it wasassociated with an increased risk of preterm deliveryOR9.000(95%CI:3.872-20.919), and its sensitivity is 73%, its specificity is 89.2%. By transvaginal ultrasound, and through measurement of cervicallength, then determine the situation of cervical ripening, the risk ofpreterm birth increased by cervical ripening isOR:69.291 (95%CI: 10.428-460.405). In the simple regression analysis ofcervical ripening and preterm birth, the risk ofpreterm birth increased bycervical ripening is OR: 19.000(95%CI:4.584-78.755).2. The level of s-relaxin of premonitory symptom of premature birth beforetreatment is: 23.832±15. 085, the level of s-relaxin the seventhdays after treatment is:14. 159±10.228. There is a significantdifference between the two (P＜0.05). Table 9 is to analyse the logisticregression about the relationship between cervical ripening of pretermbirth and the level of relaxin, this shows that an increased risk of pretermdelivery which is associated with the level of relaxin is OR:76.777(95%CI: 11.148-528.788). Apply the examination of X~2 analysis,from table 10, it shows there is no association between the raising level ofs-relaxin (＞13ng/ml) and cervical ripening.3. The level of s-relaxin of premonitory symptom of premature birth beforegiving birth is: 18.611±11.540, the s-relaxin level of the pregnantin the third day is:11.526±7.558. There is a very significantdifference between the two(P＜0.01).Conclusion:1 The increased s-relaxin level has the substantial connection with the pregnantswho have cervical shrink and preterm prelabour rupture of menbranes. Theincreasing s-relaxin (≥13ng/ml) can be as a predictor of spontaneous pretermdelivery. With the increase of weeks of pregnancy, the rate of premature birth isreducing. Weeks of pregnancy is a protective parameter. 2.The experiment showsthat ultrasonogrophic measurement of cervical length and judgement of cervicalripening is an effective target. When s-relaxin and ultrasonogrophicmeasurement of cervical length are used in predicting preterm birth at the sametime, the rate of prediction is higher. However, the cervical ripening and the happening of preterm birth may be associated with many elements. 3. Part of thepregnants who have premonitory symptom of premature birth, reduced theirs-relaxin level after treatment, and achieved the prevent miscarriage purpose ofpremonitory symptom of premature birth. There are some other elements relatedto the possibility of preterm birth.4. The s-relaxin level of pregnants who havepremonitory symptom of premature birth reduced after giving birth, and thenreminded that the regulation of changing s-relaxin level after giving birth issimilar to HCG.