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. The objective of the study was to examine the relationship between the gestational age at 17-alpha hydroxyprogesterone caproate initiation and recurrent preterm birth among women with a prior spontaneous preterm birth 16-28 weeks' gestation. This was a retrospective cohort study of women from a single tertiary care center, 2005-2016. All women with ≥1 singleton preterm births because of a spontaneous onset of contractions, preterm prelabor rupture of membranes, or painless cervical dilation between 16 and 28 weeks followed by a subsequent singleton pregnancy treated with 17-alpha hydroxyprogesterone caproate were included. Women were grouped based on quartiles of gestational age of 17-alpha hydroxyprogesterone caproate initiation (quartile 1, 140/7 to 161/7; quartile 2, 162/7 to 170/7; quartile 3, 171/7 to 186/7; and quartile 4, 190/7 to 275/7). Women with a gestational age of 17-alpha hydroxyprogesterone caproate initiation in quartiles 1 and 2 were considered to have early-start 17-alpha hydroxyprogesterone caproate; those in quartiles 3 and 4 were considered to have late-start 17-alpha hydroxyprogesterone caproate. The primary outcome was recurrent preterm birth <37 weeks' gestation. Secondary outcomes included recurrent preterm birth <34 and <28 weeks' gestation and composite major neonatal morbidity (diagnosis of grade III or IV intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, necrotizing enterocolitis stage II or III, or death). Gestational age at delivery was compared by quartile of 17-alpha hydroxyprogesterone caproate initiation using Kaplan-Meier survival curves and the log-rank test. Logistic regression models estimated odds ratios for the association between gestational age at 17-alpha hydroxyprogesterone caproate initiation and preterm birth <37 weeks' gestation, adjusting for demographics, prior pregnancy and antenatal characteristics. A total of 132 women met inclusion criteria; 52 (39.6%) experienced recurrent preterm birth <37 weeks in the studied pregnancy. 17-Alpha hydroxyprogesterone caproate was initiated at a mean 176/7 ± 2.5 weeks. Demographic and baseline characteristics were similar between women with early-start 17-alpha hydroxyprogesterone caproate (quartiles 1 and 2) compared with those with late-start 17-alpha hydroxyprogesterone caproate (quartiles 3 and 4). Women with early-start 17-alpha hydroxyprogesterone caproate trended toward lower rates of recurrent preterm birth <37 weeks compared with those with late-start 17-alpha hydroxyprogesterone caproate (41.3% vs 57.7%, P = .065). Delivery gestational age was inversely proportional to gestational age at 17-alpha hydroxyprogesterone caproate initiation (quartile 1, 374/7 weeks vs quartile 2, 365/7 vs quartile 3, 361/7 weeks vs quartile 4, 340/7, P = .007). In Kaplan-Meier survival analyses, these differences in delivery gestational age by 17-alpha hydroxyprogesterone caproate initiation quartile persisted across pregnancy (log-rank P < .001). In regression models, later initiation of 17-alpha hydroxyprogesterone caproate was significantly associated with increased odds of preterm birth <37 weeks. Women with early 17-alpha hydroxyprogesterone caproate initiation also had lower rates of major neonatal morbidity than those with later 17-alpha hydroxyprogesterone caproate initiation (1.5% vs 14.3%, P = .005). 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.

Ning A ，Vladutiu CJ ，Dotters-Katz SK ，Goodnight WH ，Manuck TA ... -  《-》

Nonresponse to 17-alpha hydroxyprogesterone caproate for recurrent spontaneous preterm birth prevention: clinical prediction and generation of a risk scoring system.

Spontaneous preterm birth remains a leading cause of neonatal morbidity and mortality among nonanomalous neonates in the United States. Spontaneous preterm birth tends to recur at similar gestational ages. Intramuscular 17-alpha hydroxyprogesterone caproate reduces the risk of recurrent spontaneous preterm birth. Unfortunately, one-third of high-risk women will have a recurrent spontaneous preterm birth despite 17-alpha hydroxyprogesterone caproate therapy; the reasons for this variability in response are unknown. We hypothesized that clinical factors among women treated with 17-alpha hydroxyprogesterone caproate who suffer recurrent spontaneous preterm birth at a similar gestational age differ from women who deliver later, and that these associations could be used to generate a clinical scoring system to predict 17-alpha hydroxyprogesterone caproate response. Secondary analysis of a prospective, multicenter, randomized controlled trial enrolling women with ≥1 previous singleton spontaneous preterm birth <37 weeks' gestation. Participants received daily omega-3 supplementation or placebo for the prevention of recurrent preterm birth; all were provided 17-alpha hydroxyprogesterone caproate. Women were classified as a 17-alpha hydroxyprogesterone caproate responder or nonresponder by calculating the difference in delivery gestational age between the 17-alpha hydroxyprogesterone caproate-treated pregnancy and her earliest previous spontaneous preterm birth. Responders were women with pregnancy extending ≥3 weeks later compared with the delivery gestational age of their earliest previous preterm birth; nonresponders delivered earlier or within 3 weeks of the gestational age of their earliest previous preterm birth. A risk score for nonresponse to 17-alpha hydroxyprogesterone caproate was generated from regression models via the use of clinical predictors and was validated in an independent population. Data were analyzed with multivariable logistic regression. A total of 754 women met inclusion criteria; 159 (21%) were nonresponders. Responders delivered later on average (37.7±2.5 weeks) than nonresponders (31.5±5.3 weeks), P<.001. Among responders, 27% had a recurrent spontaneous preterm birth (vs 100% of nonresponders). Demographic characteristics were similar between responders and nonresponders. In a multivariable logistic regression model, independent risk factors for nonresponse to 17-alpha hydroxyprogesterone caproate were each additional week of gestation of the earliest previous preterm birth (odds ratio, 1.23; 95% confidence interval, 1.17-1.30, P<.001), placental abruption or significant vaginal bleeding (odds ratio, 5.60; 95% confidence interval, 2.46-12.71, P<.001), gonorrhea and/or chlamydia in the current pregnancy (odds ratio, 3.59; 95% confidence interval, 1.36-9.48, P=.010), carriage of a male fetus (odds ratio, 1.51; 95% confidence interval, 1.02-2.24, P=.040), and a penultimate preterm birth (odds ratio, 2.10; 95% confidence interval, 1.03-4.25, P=.041). These clinical factors were used to generate a risk score for nonresponse to 17-alpha hydroxyprogesterone caproate as follows: black +1, male fetus +1, penultimate preterm birth +2, gonorrhea/chlamydia +4, placental abruption +5, earliest previous preterm birth was 32-36 weeks +5. A total risk score >6 was 78% sensitive and 60% specific for predicting nonresponse to 17-alpha hydroxyprogesterone caproate (area under the curve=0.69). This scoring system was validated in an independent population of 287 women; in the validation set, a total risk score >6 performed similarly with a 65% sensitivity, 67% specificity and area under the curve of 0.66. Several clinical characteristics define women at risk for recurrent preterm birth at a similar gestational age despite 17-alpha hydroxyprogesterone caproate therapy and can be used to generate a clinical risk predictor score. These data should be refined and confirmed in other cohorts, and women at high risk for nonresponse should be targets for novel therapeutic intervention studies.

Manuck TA ，Stoddard GJ ，Fry RC ，Esplin MS ，Varner MW ... -  《-》

Predictors of response to 17-alpha hydroxyprogesterone caproate for prevention of recurrent spontaneous preterm birth.

Prematurity is the leading cause of neonatal morbidity and death among nonanomalous neonates in the United States. Intramuscular 17-alpha hydroxyprogesterone caproate injections reduce the risk of recurrent prematurity by approximately one third. Unfortunately, prophylactic 17-alpha hydroxyprogesterone caproate is not always effective, and one-third of high-risk women will have a recurrent preterm birth, despite 17-alpha hydroxyprogesterone caproate therapy. The reasons for this variability in response are unknown. Previous investigators have examined the influence of a variety of factors on 17-alpha hydroxyprogesterone caproate response but have analyzed data that used a fixed outcome of term delivery to define progesterone response. We hypothesized that the demographics, history, and pregnancy course among women who deliver at a similar gestational age with 17-alpha hydroxyprogesterone caproate for recurrent spontaneous preterm birth prevention differs when compared with those women who deliver later with 17-alpha hydroxyprogesterone caproate and that these associations could be refined by the use of a contemporary definition of 17-alpha hydroxyprogesterone caproate "responder." This was a planned secondary analysis of a prospective, multicenter, longitudinal study of women with ≥1 previous documented singleton spontaneous preterm birth at <37 weeks gestation. Data were collected at 3 prespecified gestational age epochs during pregnancy. All women who were included in this analysis received 17-alpha hydroxyprogesterone caproate during the studied pregnancy. We classified women as a 17-alpha hydroxyprogesterone caproate responder or nonresponder by calculating the difference in delivery gestational age between the 17-alpha hydroxyprogesterone caproate-treated pregnancy and her earliest spontaneous preterm birth. Responders were defined as those with pregnancy that extended ≥3 weeks later with 17-alpha hydroxyprogesterone caproate, compared with the delivery gestational age of their earliest previous spontaneous preterm birth. Data were analyzed with the use of chi-square test, t-test, and logistic regression. One hundred fifty-five women met the inclusion criteria. The 118 responders delivered later on average (37.7 weeks gestation) than the 37 nonresponders (33.5 weeks gestation; P < .001). Among responders, 32% (38/118 women) had a recurrent spontaneous preterm birth. Demographics (age, race/ethnicity, education, and parity) were similar between groups. In the regression model, the gestational age of the previous spontaneous preterm birth (odds ratio, 0.68; 95% confidence interval, 0.56-0.82; P < .001), vaginal bleeding/abruption in the current pregnancy (odds ratio, 0.24; 95% confidence interval, 0.06-0.88; P = .031), and first-degree family history of spontaneous preterm birth (odds ratio, 0.37; 95% confidence interval, 0.15-0.88; P = .024) were associated with response to 17-alpha hydroxyprogesterone caproate. Because women with a penultimate preterm pregnancy were more likely to be 17-alpha hydroxyprogesterone caproate nonresponders, we performed an additional limited analysis examining only the 130 women whose penultimate pregnancy was preterm. In regression models, the results were similar to those in the main cohort. Several historic and current pregnancy characteristics define women who are at risk for recurrent preterm birth at a similar gestational age, despite 17-alpha hydroxyprogesterone caproate therapy. These data should be studied prospectively in larger cohorts and combined with genetic and environmental data to identify women who are most likely to benefit from this intervention.

Manuck TA ，Esplin MS ，Biggio J ，Bukowski R ，Parry S ，Zhang H ，Huang H ，Varner MW ，Andrews W ，Saade G ，Sadovsky Y ，Reddy UM ，Ilekis J ，Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Genomics and Proteomics Network for Preterm Birth Research (GPN-PBR) ... -  《-》

17-alpha Hydroxyprogesterone caproate did not reduce the rate of recurrent preterm birth in a prospective cohort study.

17-alpha Hydroxyprogesterone caproate for prevention of recurrent preterm birth is recommended for use in the United States. We sought to assess the clinical effectiveness of 17-alpha hydroxyprogesterone caproate to prevent recurrent preterm birth ≤35 weeks compared to similar births in our obstetric population prior to the implementation of 17-alpha hydroxyprogesterone caproate. This was a prospective cohort study of 17-alpha hydroxyprogesterone caproate in our obstetric population. The primary outcome was the recurrence of birth ≤35 weeks for the entire study cohort compared to a historical referent rate of 16.8% of recurrent preterm birth in our population. There were 3 secondary outcomes. First, did 17-alpha hydroxyprogesterone caproate modify a woman's history of preterm birth when taking into account her prior number and sequence of preterm and term births? Second, was recurrence of preterm birth related to 17-alpha hydroxyprogesterone caproate plasma concentration? Third, was duration of pregnancy modified by 17-alpha hydroxyprogesterone caproate treatment compared to a prior preterm birth? From January 2012 through March 2016, 430 consecutive women with prior births ≤35 weeks were treated with 17-alpha hydroxyprogesterone caproate. Nearly two thirds of the women (N = 267) began injections ≤18 weeks and 394 (92%) received a scheduled weekly injection within 10 days of reaching 35 weeks or delivery. The overall rate of recurrent preterm birth was 25% (N = 106) for the entire cohort compared to the 16.8% expected rate (P = 1.0). The 3 secondary outcomes were also negative. First, 17-alpha hydroxyprogesterone caproate did not significantly reduce the rates of recurrence regardless of prior preterm birth number or sequence. Second, plasma concentrations of 17-alpha hydroxyprogesterone caproate were not different (P = .17 at 24 weeks; P = .38 at 32 weeks) between women delivered ≤35 weeks and those delivered later in pregnancy. Third, the mean (±SD) interval in weeks of recurrent preterm birth before 17-alpha hydroxyprogesterone caproate use was 0.4 ± 5.3 weeks and the interval of recurrent preterm birth after 17-alpha hydroxyprogesterone caproate treatment was 0.1 ± 4.7 weeks (P = .63). A side effect of weekly 17-alpha hydroxyprogesterone caproate injections was an increase in gestational diabetes. Specifically, the rate of gestational diabetes was 13.4% in 17-alpha hydroxyprogesterone caproate-treated women compared to 8% in case-matched controls (P = .001). 17-alpha Hydroxyprogesterone caproate was ineffective for prevention of recurrent preterm birth and was associated with an increased rate of gestational diabetes.

Nelson DB ，McIntire DD ，McDonald J ，Gard J ，Turrichi P ，Leveno KJ ... -  《-》

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. We sought to: (1) determine the relation between 17-alpha hydroxyprogesterone caproate plasma concentrations and single nucleotide polymorphisms in CYP3A4 and CYP3A5; (2) test the association between progesterone receptor single nucleotide polymorphisms and spontaneous preterm birth; and (3) test whether the association between plasma concentrations of 17-alpha hydroxyprogesterone caproate and spontaneous preterm birth varied by progesterone receptor single nucleotide polymorphisms. In this secondary analysis, we evaluated genetic polymorphism in 268 pregnant women treated with 17-alpha hydroxyprogesterone caproate, who participated in a placebo-controlled trial to evaluate the benefit of omega-3 supplementation in women with history of spontaneous preterm birth. Trough plasma concentrations of 17-alpha hydroxyprogesterone caproate were measured between 25-28 weeks of gestation after a minimum of 5 injections of 17-alpha hydroxyprogesterone caproate. We extracted DNA from maternal blood samples and genotyped the samples using TaqMan (Applied Biosystems, Foster City, CA) single nucleotide polymorphism genotyping assays for the following single nucleotide polymorphisms: CYP3A4*1B, CYP3A4*1G, CYP3A4*22, and CYP3A5*3; and rs578029, rs471767, rs666553, rs503362, and rs500760 for progesteronereceptor. We adjusted for prepregnancy body mass index, race, and treatment group in a multivariable analysis. Differences in the plasma concentrations of 17-alpha hydroxyprogesterone caproate by genotype were evaluated for each CYP single nucleotide polymorphism using general linear models. The association between progesterone receptor single nucleotide polymorphisms and frequency of spontaneous preterm birth was tested using logistic regression. A logistic model also tested interaction between 17-alpha hydroxyprogesterone caproate concentrations with each progesterone receptor single nucleotide polymorphism for the outcome of spontaneous preterm birth. The association between CYP single nucleotide polymorphisms *22, *1G, *1B, and *3 and trough plasma concentrations of 17-alpha hydroxyprogesterone caproate was not statistically significant (P = .68, .44, .08, and .44, respectively). In an adjusted logistic regression model, progesterone receptor single nucleotide polymorphisms rs578029, rs471767, rs666553, rs503362, and rs500760 were not associated with the frequency of spontaneous preterm birth (P = .29, .10, .76, .09, and .43, respectively). Low trough plasma concentrations of 17-alpha hydroxyprogesterone caproate were statistically associated with a higher frequency of spontaneous preterm birth (odds ratio, 0.78; 95% confidence ratio, 0.61-0.99; P = .04 for trend across quartiles), however no significant interaction with the progesterone receptor single nucleotide polymorphisms rs578029, rs471767, rs666553, rs503362, and rs500760 was observed (P = .13, .08, .10, .08, and .13, respectively). 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.

Bustos ML ，Caritis SN ，Jablonski KA ，Reddy UM ，Sorokin Y ，Manuck T ，Varner MW ，Wapner RJ ，Iams JD ，Carpenter MW ，Peaceman AM ，Mercer BM ，Sciscione A ，Rouse DJ ，Ramin SM ，Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network ... -  《-》