Risk factors associated with preterm labor, with special emphasis on preterm premature rupture of membranes and severe preterm labor

Abstract

Background: Preterm labor (PTL) can lead to preterm birth, which can cause neonatal mortality and morbidity. Preterm premature rupture of membranes (PPROM) and severe PTL (SPTL) are serious PTL subtypes. Hereby, we aimed to investigate risk factors associated with PPROM and SPTL, among Egyptian women. Methods: In this case-control study, 117 women were enrolled without any known medical risk for PTL. The control group (n = 45) had term labor (≥37 gestational weeks), while the case group (n = 72) had PTL (<37 gestational weeks). The PTL group was subdivided into those with PPROM (n = 18) and those with intact membranes (n = 54). Fifty-two PTL women, with accurate gestational age, were subdivided into SPTL (n = 31, ≤34 gestational weeks) and mild preterm labor (MPTL; n = 21, 35-36 gestational weeks). All groups were examined for different demographic characteristics, obstetrical history, clinical signs, and vaginal and urinary tract infections. Nominal logistic regression was applied to investigate significant variables associated with PPROM and intact membranes PTL, while ordinal logistic regression was used to estimate significant variables associated with SPTL and MPTL. Results: The final multivariate nominal model identified abortion history, heavy vaginal bleeding history, and elevated vaginal pH as significant predictors of PPROM. The same model identified age <20 years old, abortion history, heavy growth of vaginal organisms, and any growth of Gram-negative bacilli as the significant predictors of intact membranes PTL. The final multivariate ordinal model identified age <20 years old, abortion history, vaginal pH, and heavy growth of vaginal organisms as the significant predictors of SPTL and MPTL. Conclusion: Age <20 years old, abortion history, heavy vaginal bleeding, vaginal pH, and heavy growth of vaginal organisms were reported as risk factors for PPROM and SPTL. Most of these factors are related to infection; therefore, proper infection control is recommended during prenatal and antenatal care.

Perinatal Outcomes of Pregnancies with Preterm Premature Rupture of Membranes after 34 Weeks of Gestation

“…Also Maryuni and Kurniasih (14) found that mothers < 20 years and > 35 years were 2.6 times at risk of PPROM. Hosny et al (15) concluded that women below the age of 20 years were at high risk of PPROM. A study done by Linehan et al (16) found that the highest incidence of PROM was in the 18-35-years old group (74.6%) versus 73.2% in our study.…”

Prolactin Protects the Structural Integrity of Human Fetal Membranes by Downregulating Inflammation-induced Secretion of Matrix Metalloproteinases

“…pPROM is one of the main causes of neonatal mortality and morbidity, the main risk factors of this gyneco-obstetric pathology are related to the infection (Hosny et al 2019). Fetal membranes express innate immunity receptors that recognize the molecular patterns of pathogenic microorganisms such as LPS of E. coli, which results in a proinflammatory response as a part of a defense mechanism against the immunological challenge ( Abrahams et al 2004;Motedayyen et al 2018).…”

Preterm Labor, a Syndrome Attributed to the Combination of External and Internal Factors

“…Maternal age (<18 years, or >40 years), ethnicity (Black race), body mass index (<19 kg/m 2 ), smoking, stress (depression, anxiety), heavy physical labor, education, poverty, and other social factors have all been reported to be associated with sPTL. 34,35 The intrinsic factors like maternal genetic variations, immune response, obstetric factors (such as prior preterm delivery, uterine curettage, cervical factors, multiple gestations, and adverse outcome of previous term pregnancy 33 ) may also increase the risk of sPTL. Moreover, some diseases or disorders during pregnancy, such as kidney dysfunction, 36 renovascular disease, 37 cesarean section at term, 38 history of surgery for endometriosis 39 or cervical intraepithelial neoplasia, 40 were all associated with an increased risk of sPTL.…”

“…Maternal age (<18 years, or >40 years), ethnicity (Black race), body mass index (<19 kg/m 2 ), smoking, stress (depression, anxiety), heavy physical labor, education, poverty, and other social factors have all been reported to be associated with sPTL 34,35 . The intrinsic factors like maternal genetic variations, immune response, obstetric factors (such as prior preterm delivery, uterine curettage, cervical factors, multiple gestations, and adverse outcome of previous term pregnancy 33 ) may also increase the risk of sPTL.…”