American journal of obstetrics and gynecology
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Am. J. Obstet. Gynecol. · Dec 2016
The combination tocolytic effect of magnesium sulfate and an oxytocin receptor antagonist in myometrium from singleton and twin pregnancies.
Preterm birth at <37 weeks of gestation is the most common and costly complication of pregnancy and remains the leading cause of neonatal morbidity, death, and reduced achievement in surviving infants. Magnesium sulfate is 1 class of tocolytics for threatened preterm labor; however, its clinical efficacy has been questioned. Twin pregnancies are at increased risk of preterm delivery compared with singleton gestations, which suggests that there is twin-specific risk to preterm delivery in twins. The prevention strategies that are applied to singleton pregnancies, however, have not been shown to be effective in twin pregnancies. ⋯ Magnesium sulfate is equipotent in suppressing contractions in singleton and twin myometrium. Oxytocin (0.5 nmol/L) significantly reduces the tocolytic potency of magnesium sulfate, which may explain, in part, magnesium sulfate's poor efficacy in vivo; however, this can be reversed partially by the use of an oxytocin receptor antagonist. Combination tocolysis that involves oxytocin receptor antagonists requires further investigation.
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Am. J. Obstet. Gynecol. · Dec 2016
The predictive value of quantitative fibronectin testing in combination with cervical length measurement in symptomatic women.
The combination of the qualitative fetal fibronectin test and cervical length measurement has a high negative predictive value for preterm birth within 7 days; however, positive prediction is poor. A new bedside quantitative fetal fibronectin test showed potential additional value over the conventional qualitative test, but there is limited evidence on the combination with cervical length measurement. ⋯ In women with threatened preterm birth, quantitative fibronectin testing alone performs equal to the combination of cervical length and qualitative fibronectin. Possibly, the combination of quantitative fibronectin testing and cervical length increases this predictive capacity. Cost-effectiveness analysis and the availability of these tests in a local setting should determine the final choice.
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Am. J. Obstet. Gynecol. · Dec 2016
Multifactorial contributors to the severity of chronic pelvic pain in women.
Chronic pelvic pain affects ∼15% of women, and is associated with significant societal cost and impact on women's health. Identifying factors involved in chronic pelvic pain is challenging due to its multifactorial nature and confounding between potential factors. For example, while some women with endometriosis have chronic pelvic pain, there may be comorbid conditions that are implicated in the chronic pelvic pain rather than the endometriosis itself. ⋯ Multifactorial variables independently associated with severity of chronic pelvic pain were identified, ranging from myofascial/musculoskeletal, urological, family history, and psycho-social factors. Continued research is required to validate these factors and to determine whether any are potentially modifiable for the management of chronic pelvic pain.
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Am. J. Obstet. Gynecol. · Dec 2016
In vivo uteroplacental release of placental growth factor and soluble Fms-like tyrosine kinase-1 in normal and preeclamptic pregnancies.
Preeclampsia is characterized by maternal endothelial dysfunction, which underlies a highly diverse clinical presentation. The pathophysiologic condition remains to be unraveled fully, but interplay between factors that are released from the placenta and maternal vascular vulnerability is likely. An imbalance in circulating angiogenic factors is a prominent feature of preeclampsia; placental growth factor and soluble Fms-like tyrosine kinase 1 have been implemented as biomarkers of placental function and preeclampsia. Their test accuracies are limited in a clinical setting, which urges better insight into their production and removal. Current data suggest that placental growth factor and soluble Fms-like tyrosine kinase 1 are released from the placenta. Both the circulating levels and the placental expression are altered in preeclamptic pregnancies. However, in vivo placental release has not been determined in human pregnancies. Moreover, there is evidence that extra-placental tissues might contribute to the circulating levels placental growth factor and soluble Fms-like tyrosine kinase 1 in normal and preeclamptic pregnancies. ⋯ Our findings are consistent with a net release of soluble Fms-like tyrosine kinase 1 from the placenta in early-onset preeclampsia. This study demonstrated a placental release of placental growth factor to the maternal circulation but could not demonstrate that this release was impaired in the preeclamptic group. We could not find evidence of systemic endothelial release of placental growth factor and soluble Fms-like tyrosine kinase 1 by analyzing the arteriovenous differences in the forearm. This study contributes to the pathophysiologic understanding of preeclampsia by the use of the clinical setting to test current concepts in vivo and underscores that studies of in vivo degradation rates of placentally released compounds are needed.
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Am. J. Obstet. Gynecol. · Dec 2016
Early-onset preeclampsia appears to discourage subsequent pregnancy but the risks may be overestimated.
Early-onset preeclampsia is associated with adverse maternal and perinatal outcomes. For women who consider another pregnancy after one complicated by early-onset preeclampsia, the likelihood of recurrence and the subsequent pregnancy outcome for themselves and their babies are pertinent considerations. ⋯ Women with early-onset preeclampsia in a first pregnancy appear less likely than women without preeclampsia to have a subsequent pregnancy. Maternal and perinatal outcomes in the subsequent pregnancy are generally better than in the first; most women will not have recurrent preeclampsia, and those who do usually will give birth at a greater gestational age compared with their index birth.