Salivary progesterone as a biochemical marker to predict early preterm birth in asymptomatic high‐risk women

Abstract

Objective To evaluate salivary progesterone as a predictor of early preterm birth (PTB) and compare it with transvaginal sonographic (TVS) cervical length in asymptomatic high-risk women.Design Prospective study.Setting Departments of Obstetrics and Gynaecology and Biochemistry at UCMS & GTBH, Delhi, India.Sample Ninety pregnant women.Methods The progesterone concentration in saliva of asymptomatic pregnant women at high risk for preterm delivery was estimated by immunoassay, and cervical length was measured by TVS, at the first antenatal visit at 24-28 weeks of gestation, and then repeated 3-4 weeks later.Main outcome measures Early PTB, mean and critical cut-off values of salivary progesterone, and a diagnostic value comparison of salivary progesterone with TVS cervical length.Results The mean value of salivary progesterone was significantly lower in all women who delivered at <37 weeks of gestation (n = 38), compared with the term group (n = 52; P < 0.001). Salivary progesterone decreased significantly from the first to the second visit, with the maximum decrease observed in women who delivered at <34 weeks of gestation (29.6%, 95% CI 17.8-41.4%, P < 0.002). The single predictive critical cut-off value for salivary progesterone was 2575 pg/ml, below which more than 80% of women delivered prematurely before 34 weeks of gestation, with sensitivity, specificity, and positive and negative predictive values of 83% (95% CI 58.6-96.4%), 86% (95% CI 75.9-93.1%), 60% (95% CI 38.6-78.8%) and 95% (95% CI 87.1-99.0%), respectively. The TVS cervical length decreased significantly (P < 0.001) in the women who delivered prematurely.Conclusions Low salivary progesterone concentration can be used for predicting early PTB in asymptomatic high-risk women.

Plasma progesterone, estradiol, and unconjugated estriol concentrations in twin pregnancies: Relation with cervical length and preterm delivery

“…Whereas some later studies have also found lower plasma progesterone concentrations in the third trimester in preterm vs term labor in women with a previous preterm birth, 4 others have found no difference in maternal progesterone concentrations in either serum or amniotic fluid. 14 A more consistent finding has been lower progesterone : estradiol ratios in women in labor compared with women not in labor both preterm and term. 14 A more consistent finding has been lower progesterone : estradiol ratios in women in labor compared with women not in labor both preterm and term.…”

“…[4][5][6][7][8][9][10][11][12] Recent studies have found low saliva progesterone concentrations in women with preterm labor 13 and preterm delivery. 3,6,9,11 Progesterone, estradiol, and estriol in relation to preterm delivery have mainly been investigated in singleton pregnancies 3,4,6,7,[9][10][11][12][13][14] and few results have been published from multiple pregnancies. 3,6,9,11 Progesterone, estradiol, and estriol in relation to preterm delivery have mainly been investigated in singleton pregnancies 3,4,6,7,[9][10][11][12][13][14] and few results have been published from multiple pregnancies.…”

Bitter taste receptors as targets for tocolytics in preterm labor therapy

“…Progesterone is a key hormonal regulator of the female reproductive system and plays a major role in preparing the uterus for implantation and in the establishment and maintenance of pregnancy (32,33). PTB in women is associated with changes in circulating hormones such as progesterone deficits (34)(35)(36)(37)(38) or with inadequate responses to progesterone (32,39). To further demonstrate the effectiveness of bitter tastants in preventing PTB, we established another mouse model of preterm labor with the progesterone receptor antagonist RU-486.…”

Placental hormone profiles as predictors of preterm birth in twin pregnancy: A prospective cohort study

“…Three later studies, two in saliva and one on serum, suggested that repeating measurements of hormones to generate a “hormone profile” may be more useful than a single measure [8–10]. Priya et al .…”

“…and Lachelin et al . found that low saliva P4 between 24–34 weeks was associated with spontaneous PTB before 34 weeks [8,9]. Smith et al .…”