RESUMEN
INTRODUCTION: Postterm and late-term pregnancies still remain a serious health problem, and underlying exact mechanisms are not fully elucidated. These mechanisms are influenced by many factors. OBJECTIVE: The aim of this study was to investigate the relationship between plasma oxytocin and oxytocin receptor levels and oxytocin receptor polymorphisms in term and late-term pregnant women. METHODS: Sixty-eight singleton pregnant women with late-term pregnancy and 83 singleton pregnant women with term parturition were included in this study. A comparison was performed between pregnancies and neonates born at term (37 0/7 and 41 6/7 weeks' gestation). Plasma oxytocin, oxytocin receptor, estradiol, and progesterone levels were measured by using enzyme-linked immunosorbent assay kits. TaqMan® SNP Genotyping Assays and qPCR ProbesMaster were used to investigate the polymorphisms of rs237911, rs2228485, rs53576, and rs2254298. RESULTS: There was not any difference in gene distributions of 4 common single-nucleotide polymorphisms of oxytocin receptor of rs237911, rs2228485, rs53576, and rs2254298 between subjects in late-term and term pregnancy groups. With rs53576 of the GG genotype, serum oxytocin levels were 21.50 ± 10.69 (ng/L) in the late-term group and 62.71 ± 18.01 (ng/L) in the term group (p = 0.049). Oxytocin receptor levels in the late-term and term pregnancy groups of the GG genotype were 17.92 ± 8.15 (pg/mL) and 45.77 ± 11.66 (pg/mL), respectively (p = 0.046). CONCLUSION: Our findings suggest that the rs53576 oxytocin receptor single-nucleotide polymorphism is associated with late-term pregnancy through acting by direct modulation of oxytocin and oxytocin receptor levels.
Asunto(s)
Polimorfismo de Nucleótido Simple , Embarazo Prolongado/sangre , Receptores de Oxitocina/sangre , Receptores de Oxitocina/genética , Nacimiento a Término/sangre , Adulto , Femenino , Genotipo , Edad Gestacional , Humanos , Recién Nacido , Oxitocina/sangre , Embarazo , Embarazo Prolongado/genética , Nacimiento a Término/genética , TurquíaRESUMEN
OBJECTIVE: To estimate intergenerational recurrence risk of prolonged and post-term gestational age. DESIGN: Population-based cohort study. SETTING: Norway, 1967-2006. POPULATION: Intergenerational data from the Medical Birth Registry of Norway of singleton mothers and fathers giving birth to singleton children: 478 627 mother-child units and 353 164 father-child units. A combined mother-father-child file including 295 455 trios was also used. METHODS: Relative risks were obtained from contingency tables and relative risk modelling. MAIN OUTCOME MEASURES: Gestational age ≥41 weeks (≥287 days), ≥42 weeks (≥294 days) and ≥43 weeks (≥301 days) of gestation in the second generation. RESULTS: A post-term mother (≥42 weeks) had a 49% increased risk of giving birth to a child at ≥42 weeks (relative risk [RR] 1.49, 95% CI 1.47-1.51) and a post-term father had a 23% increased risk of fathering a child at ≥42 weeks (RR 1.23, 95%CI 1.20-1.25). The RRs for delivery at ≥41 weeks were 1.29 (1.28-1.30) and 1.14 (1.13-1.16) for mother and father, respectively, and for ≥43 weeks 1.55 (1.50-1.59) and 1.22 (1.17-1.27). The RR of a pregnancy at ≥42 weeks in the second generation was 1.76 (1.68-1.84) if both mother and father were born post-term. Adjustment for maternal age in both generations, fetal sex in the second generation, parity, and maternal and paternal birthweight did not influence the risk estimates. CONCLUSIONS: There is a familial factor related to recurrence of prolonged pregnancy across generations and both mother and father seem to contribute.
Asunto(s)
Padre/estadística & datos numéricos , Madres/estadística & datos numéricos , Embarazo Prolongado/genética , Adulto , Estudios de Cohortes , Femenino , Humanos , Masculino , Edad Materna , Noruega/epidemiología , Linaje , Embarazo , Embarazo Prolongado/epidemiología , Recurrencia , Medición de Riesgo , Factores de Riesgo , Adulto JovenAsunto(s)
Embarazo Prolongado/genética , Femenino , Humanos , Masculino , Embarazo , Gemelos Dicigóticos , Gemelos MonocigóticosRESUMEN
OBJECTIVE: The purpose of this study was to test a possible genetic component to prolonged gestation. STUDY DESIGN: The gestational duration of single, first pregnancies by both female and male twins was obtained by linking the Danish Twin Registry, The Danish Civil Registration System, and the Danish Medical Birth Register. A total of 2588 same-sex twin pairs of whom both cotwins became parents during 1978 to 1996 were identified. RESULTS: The concordance rate for female twin pairs for a gestation of > or =41 weeks and > or =42 weeks was higher for monozygotic twin pairs than for dizygotic twin pairs, which indicates genetic effects. Biometric modeling suggested that genetic factors account for 23% to 30% of the liability to prolonged gestation. The difference in concordance rate between monozygotic and dizygotic male twin pairs was small, and the best fitting model indicated no genetic factors. CONCLUSION: Maternal genes influence prolonged gestation. However, a substantial paternal genetic influence through the fetus was not found.
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Embarazo Prolongado/genética , Dinamarca , Femenino , Humanos , Masculino , Embarazo , Gemelos Dicigóticos , Gemelos MonocigóticosRESUMEN
BACKGROUND: We conducted a cohort study in an attempt to determine whether prolonged pregnancy in mother is a risk factor for prolonged pregnancy in daughter, and if previous prolonged pregnancy is a risk factor for prolonged pregnancy in subsequent pregnancy. METHODS: Data from the Swedish Medical Birth Registry were combined with a local registry of births (1955-1990). Mother-daughter pairs (with events of delivery in each generation) were identified. Relative risk (RR) and its 95% confidence interval (CI) were calculated and population attributable proportion was estimated when appropriate. RESULTS: If mother had had prolonged pregnancy at delivery of daughter the relative risk (RR) of prolonged pregnancy in daughter was moderately raised (RR = 1.3; CI : 1.0-1.7) with population attributable proportions ranging between 2.1% and 4.6%. If previous pregnancy had been prolonged, the RR of prolonged pregnancy at subsequent birth was increased 2-3 fold with population attributable proportions of 12.5% to 15.8%. Possible confounders such as mother's parity, age and maternal age did not alter the risks. CONCLUSIONS: Although moderate, prolonged pregnancy in mother may be a risk factor for prolonged pregnancy in daughter. A previous prolonged pregnancy increases the risk of prolonged pregnancy in a subsequent birth. However, the familial factor of prolonged pregnancy explains just a minor part of its occurrence in the population (due to small population attributable proportions).
Asunto(s)
Embarazo Prolongado , Adolescente , Adulto , Estudios de Cohortes , Intervalos de Confianza , Femenino , Edad Gestacional , Humanos , Edad Materna , Embarazo , Embarazo Prolongado/genética , Prevalencia , Recurrencia , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , Suecia/epidemiologíaRESUMEN
In fetal lung the amounts of mRNAs encoding fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC) and ATP citrate lyase (ACL) increase in late gestation and drop around birth. To study the mechanism of the perinatal decrease, pregnancy was prolonged from 22 (term) to 25 days in rats with daily injections of progesterone. Progesterone did not affect the levels of lipogenic enzyme mRNAs in fetal lung prior to term, but significantly delayed the perinatal decrease in the levels of lung FAS and ACC mRNA. Although for ACL mRNA abundance the differences were not statistically significant, its pattern in the control and progesterone groups were similar to those of FAS and ACC mRNA. Malic enzyme mRNA did not change between 20 and 25 days after conception in either group. These results suggest that the decrease in FAS and ACC mRNA at term can be partially explained by labor, delivery, air-breathing or switch from carbohydrate to fat metabolism.