Risk Factors For Premature Birth Research Articles

Does Antenatal Tobacco or Alcohol Exposure Influence a Child's Cerebral Palsy? A Population-Based Study

Antenatal tobacco and alcohol exposure are established risk factors for premature birth and an independent risk factor for cerebral palsy. Both exert adverse effects on fetal development. In children with cerebral palsy, whether antenatal exposure to tobacco or alcohol is associated with a difference in clinical profile remains unknown. The Quebec Cerebral Palsy Registry was used to compare neurologic subtypes, gross motor functional impairment, and comorbidities in children with cerebral palsy who were or were not prenatally exposed to alcohol or tobacco. Information on in utero exposure was available in 249 children with cerebral palsy born from 1999-2002, of whom 77 were exposed to alcohol and 62 to tobacco in utero. No association was evident between exposure to tobacco or alcohol during pregnancy and neurologic subtype, Gross Motor Function Classification System score, mean number of comorbidities experienced, or each of eight comorbidities explored. Adjusting for prematurity or low birth weight exerted no effect on these results. In utero exposure to tobacco or alcohol does not assist in predicting clinical profiles of cerebral palsy.

Obstetric and neonatal outcome after surgical treatment of cervical dysplasia

Conization is the gold standard today for the management of severe cervical dysplasia. However, with the increasing delay until first pregnancy, obstetric follow-up of patients with a history of conization is a growing concern. Retrospective case-control study using data from the electronic database of a university hospital. We compared the obstetric and neonatal outcome of 106 pregnancies delivered after conization with the outcome of 212 pregnancies of patients with no history of conization. A significant reduction in the mean gestational age at delivery (38.23 ± 2.51 weeks vs. 39.15 ± 1.56 weeks) was observed, together with a higher rate of premature rupture of the membrane (9.4% vs. 1.9%), premature onset of labor (9.4% vs. 2.4%), premature delivery (17% vs. 3.8%) and neonatal hospitalization (17.9% vs. 6.6%) in the group of patients with history of conization. Children born to women who had surgery had a significantly lower birth weight (3146.9 ± 611 g vs. 3347.3 ± 502 g) and size (49.1 ± 2.6 cm vs. 50.0 cm ± 2.2 cm) than those of the control group. Furthermore, these children were more frequently admitted in the neonatal intensive care unit (22.6% vs. 10.4%, p=0.004). Conization is an important risk factor for premature birth and women with a history of conization require cautious obstetric management during pregnancy. Anti-HPV vaccination and proactive surveillance of low-grade or moderate dysplasia, instead of immediate surgery, should be encouraged in young patients.

The progesterone receptor gene polymorphism as factor of risk for the preterm delivery

to investigate the association between gene polymorphism of the progesterone receptor (PROGINS) and the risk of premature birth. In this case-control study, 57 women with previous premature delivery (Case Group) and 57 patients with delivery at term in the current pregnancy and no history of preterm delivery (Control Group) were selected. A 10 mL amount of peripheral blood was collected by venipuncture and genomic DNA was extracted followed by the polymerase chain reaction (PCR) under specific conditions for this polymorphism and 2% agarose gel electrophoresis. The bands were visualized with an ultraviolet light transilluminator. Genotype and allele PROGINS frequencies were compared between the two groups by the χ2 test, with the level of significance set at value p < 0.05. The Odds Ratio (OR) was also used, with 95% confidence intervals. PROGINS genotypic frequencies were 75.4% T1/T1, 22.8% T1/T2 and 1.8% T2/T2 in the Group with Preterm Delivery and 80.7% T1/T1, 19.3% T1/T2 and 0% T2/T2 in the term Delivery Group. There were no differences between groups when genotype and allele frequencies were analyzed: p = 0.4 (OR = 0.7) and p = 0.4 (OR = 0.7). the present study suggests that the presence of PROGINS polymorphism in our population does not constitute a risk factor for premature birth.

Riesgo de Complicaciones Perinatales en Embarazadas con Periodontitis Moderada y Severa, en la Ciudad de Córdoba. Argentina

ObjectivesTo evaluate moderate to severe Periodontitis (M/SP) in pregnant women as a risk factor for preterm birth (PTB), premature rupture of membranes (PROM) and low birth weight (LBW). MethodThis observational and prospective cohort study involved 66 pregnant women between weeks 24 and 30 of gestation, without diagnosed systemic pathologies, attending at the Maternal and Neonatology University Hospital, Cordoba, Argentina. The patients were integrated into Group 1 or Cohort exposed to risk (CER) and Group 2 or Cohort not exposed to risk (CNER) according to whether they showed or not moderate to severe PD in no less than 4 points situated in different quadrants of the mouth. The following clinical indicators were considered: Dental Plaque Index (DP); Gingival index (GI); Periodontal Depth (PD) and Clinical Attachment Level (CAL≥3mm). Later, the perinatal data was collected from the medical records, according to the Perinatal informatic system, Latin American Center of Perinatology and Human Development-Panamerican Health Organization/WHO) and submitted to under proper statistical analyses. ResultsGroup 1 or CER comprised twenty-one patients (n=21); Group 2 or CNER comprised twenty-three women. 22 pregnant women had to be excluded due to medical reasons. 13.6% of the patients gave birth before the 37th week of gestation (PTB). The Odds Ratio for prematurity was 6.06 (CI 95%; 5.86 – 7.76); 2.8 for PROM (CI 95%; 1.81 – 4.39) and no differences were found concerning LBW among the population studied. ConclusionIn the population of patients studied, moderate to severe PD in pregnant women constitute a real risk factor for premature birth as well as for premature rupture of membranes; on the other hand, these diseases would not seem to affect low birth weight.

Is Induced Abortion a Risk Factor in Subsequent Pregnancy?

The effect of elective pregnancy termination on the incidence of premature births or small-for-gestational-age (SGA) newborns in subsequent pregnancies is unclear. This retrospective cohort study assessed the influence of a history of pregnancy termination on the risk of pregnancy, frequency of premature births, and neonatal biometrics among 247,593 singleton primaparous women. Between 1998 and 2000, perinatal statistics for these women were obtained from the databases of 8 German federal states and analyzed. Women who had 1 or more previous elective pregnancy terminations based on physician interview comprised the study group; the control group included women with no history of previous terminations. The results were adjusted for confounding variables. The adjusted data show a trend for increased preterm birth (≤36 weeks of gestation) and early preterm birth (≤31 weeks of gestation) among study group women aged 18 to 20, 28 to 30, and 37 to 42 years, but the increased rate of prematurity was statistically significant only for the cohort aged 28 to 30 years. Women in this age cohort with a history of 1 or ≥2 previous elective pregnancy terminations had prematurity rates of 7.8% and 8.5%, respectively, in comparison to the control group rate of 6.5% (P < 0.001). The risk of premature birth increased with the number of earlier induced terminations. A history of previous terminations had no effect on the frequency of SGA newborns. The investigators conclude from these data that previous elective pregnancy terminations should be considered a risk factor for premature birth in subsequent pregnancies but not for SGA newborns.

Anemia during pregnancy: associated factors, and maternal and perinatal outcomes

We examined the factors associated with anemia during pregnancy (AnP) as well as the association of AnP with several maternal and neonatal outcomes in a retrospective cohort of women who had received prenatal care in the University hospital (CHU) in Toulouse (1994-2000). Computerized medical information was retrieved for 19,925 women; complete data on maternal characteristics, and maternal and perinatal outcomes were available on 16,968 women (age: 30±5 y). The prevalence of moderate anemia (hemoglobin < 10 g/dL) was 6.1%. Age (<18 y), lower level of education, multiparity, African or Asian origin, and infections were associated with AnP; odds ratio (OR) for these risk factors ranged between 1.3 (for infections) to 6.1 (African origin). Using multiple logistic regression, after accounting for maternal age, marital situation, parity, smoking, prepregnancy BMI, ethnicity, and infections during pregnancy, AnP remained independent risk factor for premature birth, cesarean delivery, hemorrhagic delivery, and infections in the newborn in the first week of life; OR (95% CI) were 1.6 (1.4-2.0), 1.5 (1.3–1.8), 1.5 (1.3–1.9), and 1.2 (1.01–1.4), respectively. These findings suggest that anemia in pregnant women is an independent and important risk factor for poor maternal and neonatal outcomes. Its prevention prior to pregnancy is therefore of ultimate public health importance.

Relationship between cervical mucus interleukin-8 concentrations and vaginal bacteria in pregnancy.

High interleukin (IL)-8 concentration in cervical mucus in the second trimester is a risk factor for premature birth. We investigated the relationship between vaginal pathogens and IL-8 in cervical mucus. In 501 women with single pregnancy, vaginal secretions were cultured for bacteria and cervical mucus IL-8 concentrations were measured between 20 and 24 gestational weeks. Lactobacillus species were detected in 56.0% of 84 subjects with high IL-8 (> or =377 ng/mL), significantly less often than in 417 subjects with IL-8 below 377 ng/mL (84.7%; P < 0.0001). Anaerobic pathogens were detected in 83.3% of high IL-8 subjects, significantly more often than in normal IL-8 subjects (43.9%; P < 0.0001). By multivariate analysis, cervical IL-8 was significantly high only in subjects without Lactobacillus species; they showed a significantly higher prematurity rate than Lactobacillus-positive subjects. Absence of vaginal Lactobacilli was associated with increased cervical IL-8 and increased risk of premature delivery.

PREMATURE BIRTH OVER 20 YEARS

The risk factors for premature birth were evaluated with an interval of 20 years. The study population comprises two one-year cohorts of parturients (n=21430) and births (n = 21710) for years 1966 and 1966. the infants burn from multiple pregnancies, infants with unknown gestational age and the prematures delivered after elective caesarean section or induced labour were excluded, which leaves infants for the 1966 and 1985 for 1985/86 cohort. Among the 1966 cohort 9 % while among 1985/86. 72% of the mothers to 1966 had passed only elementary school, while in later 1985/86 cohort 28 %. The association of prematurity and different biological factors was studied using a logistic regression model and stratification with respect to sociodemographic factors. In both cohorts placental abnormalities, vaginal bleeding, earlier low birth-weight baby and the most disadvantageous sociodemographic group were associated with prematurity. In 1966 also age under 20 and in 1985/86 cohort malformations, hypertensive disorders and smoking increased the risk of premature labour. The study showed that the incidence of prematurity has decreased by more than half over 20 years, the families social wellbeing has increased and that the effect of social factors on prematurity to less important. The biological factors are mainly are mainly the same and have the most important effect on the risk of the premturity.