American journal of obstetrics and gynecology
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Am. J. Obstet. Gynecol. · Sep 2017
Association between gestational weight gain and perinatal outcomes in women with chronic hypertension.
Gestational weight gain above or below the 2009 National Academy of Medicine guidelines has been associated with adverse maternal and neonatal outcomes. Although it has been well established that excess gestational weight gain is associated with the development of gestational hypertension and preeclampsia, the relationship between gestational weight gain and adverse perinatal outcomes among women with pregestational (chronic) hypertension is less clear. ⋯ Women with chronic hypertension who gain less weight than National Academy of Medicine guidelines experience increased odds of small-for-gestational-age neonates, whereas excess weight gain ≥20 lb over National Academy of Medicine guidelines is associated with cesarean delivery, eclampsia, 5-minute Apgar <7, neonatal intensive care unit admission, and large-for-gestational-age neonates.
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Am. J. Obstet. Gynecol. · Sep 2017
The relationship of the subtypes of preterm birth with retinopathy of prematurity.
Retinopathy of prematurity is an adverse outcome of preterm birth and is a leading cause of childhood blindness. The relationship between the subtypes of preterm birth with retinopathy of prematurity is understudied. ⋯ Type 1 or type 2 retinopathy of prematurity are adverse ocular outcomes linked with not only lower gestational age and birth weight at delivery but also with events in the intrauterine environment that trigger a preterm birth. The reduced incidence of type 1 or type 2 retinopathy of prematurity in the preterm premature rupture of the membranes group compared with other causes of preterm birth may be related to the perinatal therapies associated with preterm premature rupture of the membranes (such as corticosteroids, antibiotics, maternal-fetal surveillance), which may have an inhibitory effect on the development of retinopathy of prematurity. We suggest that the physiologic events that predispose infants to type 1 or type 2 retinopathy of prematurity begin before delivery.
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Am. J. Obstet. Gynecol. · Sep 2017
The association among cytochrome P450 3A, progesterone receptor polymorphisms, plasma 17-alpha hydroxyprogesterone caproate concentrations, and spontaneous preterm birth.
Infants born <37 weeks' gestation are of public health concern since complications associated with preterm birth are the leading cause of mortality in children <5 years of age and a major cause of morbidity and lifelong disability. The administration of 17-alpha hydroxyprogesterone caproate reduces preterm birth by 33% in women with history of spontaneous preterm birth. We demonstrated previously that plasma concentrations of 17-alpha hydroxyprogesterone caproate vary widely among pregnant women and that women with 17-alpha hydroxyprogesterone caproate plasma concentrations in the lowest quartile had spontaneous preterm birth rates of 40% vs rates of 25% in those women with higher concentrations. Thus, plasma concentrations are an important factor in determining drug efficacy but the reason 17-alpha hydroxyprogesterone caproate plasma concentrations vary so much is unclear. Predominantly, 17-alpha hydroxyprogesterone caproate is metabolized by CYP3A4 and CYP3A5 enzymes. ⋯ The frequency of recurrent spontaneous preterm birth appears to be associated with trough 17-alpha hydroxyprogesterone caproate plasma concentrations. However, the wide variation in trough 17-alpha hydroxyprogesterone caproate plasma concentrations is not attributable to polymorphisms in CYP3A4 and CYP3A5 genes. Progesterone receptor polymorphisms do not predict efficacy of 17-alpha hydroxyprogesterone caproate. The limitations of this secondary analysis include that we had a relative small sample size (n = 268) and race was self-reported by the patients.
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Am. J. Obstet. Gynecol. · Sep 2017
Gestational age at initiation of 17-alpha hydroxyprogesterone caproate and recurrent preterm birth.
Preterm birth is the leading cause of neonatal morbidity and mortality in nonanomalous neonates in the United States. Women with a previous early spontaneous preterm birth are at highest risk for recurrence. Weekly intramuscular 17-alpha hydroxyprogesterone caproate reduces the risk of recurrent prematurity. Although current guidelines recommend 17-alpha hydroxyprogesterone caproate initiation between 16 and 20 weeks, in clinical practice, 17-alpha hydroxyprogesterone caproate is started across a spectrum of gestational ages. ⋯ Rates of recurrent preterm birth among women with a prior spontaneous preterm birth 16-28 weeks are high. Women beginning 17-alpha hydroxyprogesterone caproate early deliver later and have improved neonatal outcomes. Clinicians should make every effort to facilitate 17-alpha hydroxyprogesterone caproate initiation at 16 weeks.
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Despite decades of attempts to link infectious agents to preterm birth, an exact causative microbe or community of microbes remains elusive. Nonculture 16S ribosomal RNA gene sequencing suggests important racial differences and pregnancy specific changes in the vaginal microbial communities. A recent study examining the association of the vaginal microbiome and preterm birth documented important findings but was performed in a predominantly white cohort. Given the important racial differences in bacterial communities within the vagina as well as persistent racial disparities in preterm birth, it is important to examine cohorts with varied demographic compositions. ⋯ In a predominantly African-American population, a significant decrease of vaginal microbial community richness and diversity is associated with preterm birth. The timing of this suppression appears early in pregnancy, between the first and second trimesters, suggesting that early gestation may be an ecologically important time for events that ordain subsequent term and preterm birth outcomes.