The association of different progesterone preparations with preterm birth prevention.

Objective: We aimed to compare the efficacy of commonly available progesterone preparations for preterm birth prevention. Methods: A retrospective cohort study of all women treated with progesterone to prevent preterm birth and delivered in a single university-affiliated tertiary medical-center. Four progesterone preparations were compared: vaginal Endometrin 100 mg twice daily, vaginal Crinone 8% gel 90 mg daily, vaginal Utrogestan 200 mg daily, and intramuscular 17α-hydroxyprogesterone caproate (17-OHPC) 250 mg weekly. All women were considered at risk for preterm birth according to: prior preterm birth or cervical length below 25 mm measured during the second trimester. Significant maternal morbidity, pregnancy achieved by artificial reproductive technique and cerclage placement were excluded. Primary outcome was the rate of preterm birth prior to 37 weeks of gestation. Results: Overall, 422 women were allocated to four study groups according to progesterone preparation: Endometrin 175 (41.5%), Crinone 73 (17.3%), Utrogestan 154 (36.5%), and 17-OHPC 20 (4.7%). Rates of preterm birth prior to 37 gestational weeks were lowest on the Endometrin treatment group (12.6 versus 20.5, 17.5, and 35% in the rest, p = .05). Multivariate analysis revealed that the progesterone preparation was associated with preterm birth prior to 37 gestational weeks (LR = 8.3, p = .004). The need for maternal red blood cells transfusion was significantly higher in the Endometrin subgroup (4% versus 0 in all others, p = .018). This finding remained significant after adjustment to potential confounders (LR 16.44, p < .001). Neonatal outcomes did not differ between groups. Conclusions: Different progesterone preparations prescribed to women at risk, may possess different efficacy in preventing preterm delivery prior to 37 weeks of gestation.

Inequality and Innovation: Barriers and Facilitators to 17P Administration to Prevent Preterm Birth among Medicaid Participants.

Objectives Strategies to prevent preterm birth are limited. 17 Alpha-Hydroxyprogesterone Caproate (17P) injections have been shown to be effective, but the intervention is under-used. This mixed methods study investigates barriers and facilitators to 17P administration among Medicaid and CHIP participants enrolled in Strong Start for Mothers and Newborns, a federal preterm birth prevention program. Methods Twenty-seven awardees with more than 200 sites in 30 states, the District of Columbia, and Puerto Rico enrolled approximately 46,000 women in Strong Start from 2013 to 2016. Participant data, including data on preterm birth and 17P, was collected for each woman. Intensive interviews (n = 211) conducted with Strong Start program staff and providers (n = 314) included questions about 17P provision. Results Of women whose data included a valid response regarding 17P initiation, 3919 had a prior preterm birth and current singleton pregnancy; 14.95% received 17P. Barriers to 17P administration include late entry to prenatal care, administrative burden of preauthorization, cost risks to providers, limits in scope of practice for non-physician providers, and social barriers among participants. Facilitators for provision include streamlined work flows and the option of home administration. Conclusions for Practice A universal insurance authorization process could mitigate many barriers to 17P use. Providers need continuing education regarding the effectiveness of 17P, and expanding scope of practice for non-physician prenatal care providers would increase access. Targeted program interventions can help to overcome social barriers Medicaid participants face in accessing care. Streamlined work processes and the option of home health services are two effective program-based facilitators for providing 17P to a Medicaid population.

A randomised trial to compare 200 mg micronised progesterone effervescent vaginal tablet daily with 250 mg intramuscular 17 alpha hydroxy progesterone caproate weekly for prevention of recurrent preterm birth.

For prevention of a recurrent preterm birth (PTB), intramuscular 17-α-hydroxy progesterone caproate (IM 17 OHPC) weekly is recommended. Vaginal progesterone is preferred for women at risk for PTB due to a short cervical length, but may be useful in women with a prior PTB. However, there is no consensus about the optimal vaginal formulation or its efficacy as compared to 17 OHPC to prevent recurrent PTB. We randomised 100 women with a singleton pregnancy between 16 and 24 weeks of gestation and ≥ one prior spontaneous PTB, of a singleton (>16 to <37 weeks of gestation) to receive the 200 mg vaginal progesterone effervescent tablet daily (Group A) or IM 17-OHPC, 250 mg weekly (Group B) till 37 weeks of gestation or delivery. The spontaneous PTB rate of <37 weeks was similar (20% in Group A and 20.8% in Group B, p = .918). The PTB rate of <34 weeks or <28 weeks were also comparable. The mean birth weight and other neonatal outcomes were similar in the two groups. Two neonates in Group A and four neonates in Group B required NICU admission, one of whom (Group B) died due to prematurity. Twenty percent of women in Group A and 29.2% in Group B reported adverse effects from their respective study medications (p = .408, NS). Thus, there did not appear to be a difference between vaginal progesterone and 17-OHPC when used for the prevention of a recurrent PTB. Impact statement What is already known on this subject? Progesterone administration is useful for prevention of a recurrent preterm birth (PTB) and these women are prescribed the intramuscular 17-α-hydroxy progesterone caproate (IM 17 OHPC), 250 mg, weekly. Some studies found that vaginal progesterone (once daily) is also beneficial in these women, but there is no consensus regarding its efficacy when compared to 17 OHPC, or its optimal formulation and dose. What do the results of this study add? In the present study, 100 women with a singleton pregnancy between 16 and 24 weeks of gestation and ≥ one prior spontaneous singleton PTB or mid-trimester abortion were randomised to receive 200 mg of vaginal progesterone effervescent tablet daily (Group A) or 250 mg IM 17-OHPC weekly (Group B) till 37 weeks of gestation or delivery. The spontaneous PTB rate <37 weeks was similar in the two groups (20% in Group A and 20.8% in Group B, p = .918). The PTB rate <34 weeks or <28 weeks were also comparable. The mean birth weight and other neonatal outcomes were similar. Twenty percent of women in Group A and 29.2% of women in Group B reported adverse effects from their respective study medications (p = .408, NS). Thus, there did not appear to be a difference between the vaginal progesterone effervescent tablet and 17-OHPC when used for the prevention of a recurrent PTB. What are the implications of these findings for clinical practice and/or further research? The vaginal progesterone effervescent tablet may be a suitable alternative to IM 17 OHPC to prevent recurrent PTB. Future studies should identify the most appropriate route (IM or vaginal) and vaginal progesterone formulation for PTB prevention in women at risk for a recurrent PTB and in women with a short cervical length.

Adjuvant administration of 17-α-hydroxy-progesterone caproate in women with three or more second trimester pregnancy losses undergoing cervical cerclage is no more effective than cerclage alone.

OBJECTIVE: To investigate the role of adjuvant 17-α-hydroxy-progesterone caproate (17OHP-C) in reducing the risk of preterm delivery <34 weeks and adverse perinatal outcomes in women with ≥3 second trimester pregnancy losses attributed to cervical insufficiency undergoing prophylactic cerclage. MATERIAL AND METHODS: Retrospective cohort study of women with prophylactic cerclage placed between 2006 and 2014 divided into a cohort of (i) those receiving adjuvant 17OHP-C (n=43), and (ii) controls with cerclage alone (n=59). RESULTS: Demographic characteristics were comparable in both groups. There was no significant difference in gestational age at delivery between the cerclage-17OHP-C group (33.4±5.6 weeks) and the cerclage-alone group (34.4±4.6 weeks); P=0.33. We noted a non-significant increase for deliveries <34 weeks in the cerclage-17OHP-C group (44.2%) compared to controls (28.8%) which remained non-significant after adjusting for confounders; P=0.46. There was no statistically significant difference in the rate of delivery <37, 32, 28 and 24 weeks. Adverse neonatal outcomes were comparable in both groups (cerclage-17OHP-C 48.8% vs. cerclage-alone 39%); P=0.43. CONCLUSION: Intramuscular 17OHP-C in combination with prophylactic cerclage in women with cervical insufficiency and ≥3 second trimester pregnancy losses had no synergistic effect in reducing the rate of recurrent preterm birth or improving perinatal outcomes.

Comparative Bioavailability of Hydroxyprogesterone Caproate Administered via Intramuscular Injection or Subcutaneous Autoinjector in Healthy Postmenopausal Women: A Randomized, Parallel Group, Open-label Study.

PURPOSE: The purpose of this study was to evaluate the bioavailability of hydroxyprogesterone caproate (HPC) administered as a subcutaneous injection in the back of the upper arm using a prefilled autoinjector syringe with a 27-gauge needle compared with standard intramuscular injection in the gluteus maximus using a 21-gauge needle. METHODS: Healthy postmenopausal women 50 to 75 years old were randomized in a parallel group design to receive a single SC injection of 1.1 mL (275-mg total dose) of preservative-free HPC administered using an autoinjector in the back of the upper arm or a single IM injection of 1 mL (250-mg total dose) of preservative-free HPC administered in the gluteus maximus. Blood samples were collected through 1008 hours (42 days) after injection. The primary measures were the Cmax, AUC0-t, and AUC0-∞. Secondary measures were Tmax, ke, t½, and injection site reactions captured as a treatment-emergent adverse event. FINDINGS: The pharmacokinetic population consisted of 90 individuals; 45 received subcutaneous administration and 45 received intramuscular administration. Geometric mean whole blood concentrations of HPC were comparable between administration regimens. Subcutaneous administration resulted in a higher geometric mean Cmax than intramuscular administration (7.88 vs 6.91 ng/mL), but median Tmax values were comparable (48.1 vs 49.7 hours). The least square geometric mean ratios for AUC0-168), AUC0-t, and AUC0-∞ were 102.89%, 110.25%, and 113.51%, respectively, with all 90% CIs within the 80.0% to 125.0% window that defined bioequivalence. The ratio for Cmax was 113.95% with a 90% CI of 91.94% to 141.23% but with substantial overlap of individual values between administration regimens. The geometric mean t½ of HPC was 212 hours for the subcutaneous administration and 188 hours for the intramuscular administration. The most common treatment-emergent adverse event was injection site pain (subcutaneous, 37.3%; intramuscular, 8.2%), described as mild (85%) to moderate (15%). IMPLICATIONS: Administration of HPC by SC injection of 1.1 mL (275 mg) via autoinjector is bioequivalent to IM injection of 1.0 mL (250 mg). ClinicalTrials.gov identifier: NCT02940522.

Optimal routes of administration, vehicles and timing of progesterone treatment for inhibition of delivery during pregnancy.

OBJECTIVES: Progestins, notably progesterone (P4) and 17 alpha hydroxyprogesterone caproate, are presently used to treat pregnant women at risk of preterm birth. The aim of this study was to assess the optimal treatment options for progesterone (P4) to delay delivery using a sensitive bioassay for progesterone. STUDY DESIGN: Pregnant rats, known to be highly sensitive to progestins, were treated with P4, including Prochieve® (also known as Crinone®), in various vehicles from day 13 of gestation and in late gestation, days 19 to 22, and delivery times noted. Various routes of administration of P4 and various treatment periods were studied. RESULTS: Use of micronized P4 by rectal, subcutaneous injection (sc) and topical (transdermal) administration in various oils all significantly (P<0.05-<0.001) delay delivery, but vaginal Prochieve® did not. Administration of P4 in late gestation also prevented (P<0.001) delivery even when given 8h before delivery. CONCLUSIONS: Prochieve® possesses little biological activity to suppress delivery in a sensitive bioassay system and suggests that this preparation may be of little value in prevention and inhibition of preterm birth. Further, this study shows: 1) Inhibition of delivery is increased with P4 treatments when given subcutaneously or topically. 2) P4 in fish oil provides the best vehicle for topical treatment and may be an effective treatment of preterm birth. 3) P4 in fish oil also delays delivery even when treatment begins just prior to normal delivery. 4) To prevent preterm birth in pregnant women, randomized controlled studies are needed with a potent progestin using better formulations and routes of administration.

Evaluation of Progesterone Utilization and Birth Outcomes in a State Medicaid Plan.

OBJECTIVES: Progesterone (hydroxyprogesterone caproate injection and vaginal progesterone) has been shown to reduce preterm birth (PTB) rates by a third among pregnant women at high risk. The purpose of this analysis is to report birth outcomes and medication adherence among Massachusetts Medicaid (MassHealth) members receiving progesterone, evaluate the association between member characteristics and birth outcomes and medication adherence, and compare cost of care with a prior preterm pregnancy. METHODS: This retrospective cohort study used medical claims, pharmacy claims, and prior authorization (PA) request data for MassHealth members who had a PA submitted for progesterone between January 1, 2011, and March 31, 2015. Members were excluded due to breaks in coverage, progesterone was not indicated for prevention of PTB, and if current gestational week or date of delivery was unavailable. MAIN RESULTS: A total of 418 members were screened for inclusion of whom 190 met criteria and 169 filled progesterone. Mean age was 29.2 years (SD = 5.23), and clinical comorbidities were identified in 90.5% of members. Consistent with clinical trials on progesterone effectiveness, 62.1% of members had a term delivery (37 wks of gestation). Among members with prior gestational age at delivery available, the average difference in gestational age between pregnancies was 8.25 weeks (SD = 6.11). In addition, 66.3% of members were adherent to progesterone based on proportion of days covered (PDC) of 0.8 or higher. The overall mean PDC was 0.79 (SD = 0.26). CONCLUSION: Despite similar birth outcomes in clinical trials and national trends, medication adherence is low in this state Medicaid program. Therefore, members may benefit from adherence support.

Progestogens for Maintenance Tocolysis in Women With a Short Cervix: A Randomized Controlled Trial.

OBJECTIVE: To assess the efficacy of progestogens for maintenance tocolysis in women undelivered after their first preterm labor episode. METHODS: Women with singleton pregnancies between 22 0/7 and 31 6/7 weeks of gestation with arrested preterm labor and a cervical length 25 mm or less at hospital discharge were eligible. Patients with a previous preterm birth were excluded. In a randomized controlled trial conducted in five university hospitals, women were randomized to receive vaginal progesterone (200 mg per day) or intramuscular 17α-hydroxyprogesterone caproate (341 mg per week) or to an observation groups (control group). The primary outcome was the proportion of women with preterm birth at less than 37 weeks of gestation. A sample size of 160 per group (n=480) was planned to compare vaginal progesterone and 17α-hydroxyprogesterone caproate groups with those in the control group. The sample size estimation was based on the hypothesis that the risk of experiencing preterm birth in the control group would be 30% and that 17α-hydroxyprogesterone caproate or progesterone would decrease this risk to 15%. A P value of <.025 was defined as statistically significant. At planned interim analysis (n=254), the trial was stopped for futility. RESULTS: Between July 2010 and June 2015, 257 women were eligible and 254 were subsequently randomly assigned to vaginal progesterone (n=86), 17α-hydroxyprogesterone caproate (n=87), or observation (n=81). Nineteen (8%) were excluded from the analysis because they either dropped out or information was missing, leaving 235 women available for analysis. Demographic characteristics were similar across groups. The preterm birth rate did not differ significantly between groups: 23% in the 17α-hydroxyprogesterone caproate group, 39% in the vaginal progesterone group, and 22% in the women in the control group (P=.949 for 17α-hydroxyprogesterone caproate compared with the women in the control group and P=.027 for vaginal progesterone compared with women in the control group). CONCLUSION: The use of progestogens for maintenance tocolysis in women with a short cervix did not reduce the rate of preterm birth. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT01178788.

The effect of omega-3 supplementation on pregnancy outcomes by smoking status.

BACKGROUND: Smoking during pregnancy is associated with adverse maternal and neonatal outcomes such as preterm delivery, intrauterine growth restriction, stillbirth, and low birth weight. Because smoking causes oxidative stress, some have suggested using antioxidants to counteract the effects of oxidative stress. Smokers have lower serum levels of omega-3 fatty acids, an important antioxidant, and thus, investigating whether omega-3 supplementation in smokers reduces adverse maternal and neonatal outcomes represents an important area of research. OBJECTIVE: To investigate whether the antioxidant effect of omega-3 fatty acid supplementation on the incidence of adverse pregnancy outcomes differs between smokers and nonsmokers. STUDY DESIGN: Secondary analysis of a multicenter randomized controlled trial of omega-3 supplementation for preterm delivery prevention in women with a singleton pregnancy and a history of a previous singleton spontaneous preterm delivery. Subjects were randomized to begin omega-3 or placebo before 22 weeks, which was continued until delivery. All women received 17 alpha-hydroxyprogesterone caproate intramuscularly weekly beginning between 16 and 20 weeks of gestation and continued until 36 weeks of gestation or delivery, whichever occurred first. The primary outcome was spontaneous preterm delivery. Secondary outcomes were indicated preterm delivery, any preterm delivery (spontaneous and indicated), pregnancy-associated hypertension (gestational hypertension and preeclampsia), a neonatal composite (retinopathy of prematurity, intraventricular hemorrhage grade III or IV, patent ductus arteriosus, necrotizing enterocolitis, sepsis, respiratory morbidity, or perinatal death), low birth weight (<2500 g), small for gestational age (less than the 10th percentile), and neonatal intensive care unit or intermediate nursery admission. The study population was stratified into smokers and nonsmokers, and the incidence of each outcome was compared by omega-3 supplementation versus placebo in each subgroup. Zelen tests were performed to test for homogeneity of effect in smokers and nonsmokers. RESULTS: Of 851 subjects included in the analysis, 136 (16%) smoked. Baseline characteristics between omega-3 and placebo groups did not differ in smokers or nonsmokers. Omega-3 supplementation was associated with a lower risk of spontaneous preterm delivery in smokers (relative risk, 0.56, 95% confidence interval, 0.36-0.87) but not in nonsmokers (relative risk 1.04, 95% confidence interval 0.84-1.29); P value for interaction = 0.013. Low birth weight was also less frequent in smokers receiving omega-3 supplementation (relative risk 0.57, 95% confidence interval 0.36-0.90) compared with nonsmokers (relative risk 0.93, 95% confidence interval 0.71-1.24); P value for interaction = 0.047. The effect on other secondary outcomes did not differ significantly between smokers and nonsmokers. CONCLUSION: Omega-3 supplementation in smokers may have a protective effect against recurrent spontaneous preterm delivery and low birth weight.

The association among cytochrome P450 3A, progesterone receptor polymorphisms, plasma 17-alpha hydroxyprogesterone caproate concentrations, and spontaneous preterm birth.

BACKGROUND: 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. OBJECTIVE: 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. STUDY DESIGN: 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. RESULTS: 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). CONCLUSION: 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.

Gestational age at initiation of 17-alpha hydroxyprogesterone caproate and recurrent preterm birth.

BACKGROUND: 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. OBJECTIVE: 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. STUDY DESIGN: 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. RESULTS: 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). CONCLUSION: 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.

Meta-analysis of randomized controlled trials comparing 17α-hydroxyprogesterone caproate and vaginal progesterone for the prevention of recurrent spontaneous preterm delivery.

BACKGROUND: Vaginal progesterone and 17α-hydroxyprogesterone (17α-OHP) are both used to prevent preterm delivery in women who have experienced spontaneous preterm delivery (SPTD) previously. Randomized trial data of the comparative effectiveness of these interventions have been mixed. OBJECTIVES: To compare the efficacy of intramuscular 17α-OHP and vaginal progesterone in the prevention of recurrent SPTD. SEARCH STRATEGY: Cochrane Central Register of Controlled Trials, African Journals Online, Embase, Google Scholar, ISI Web of Science, LILACS, CINAHL, PubMed, and registers of ongoing trials were searched using keywords related to 17α-OHP, vaginal progesterone, and preterm delivery. SELECTION CRITERIA: Randomized controlled trials published between January 1, 1966, and November 30, 2016, comparing 17α-OHP and vaginal progesterone for the prevention of recurrent SPTD during singleton pregnancies were included. DATA COLLECTION AND ANALYSIS: Study data were extracted and meta-analyses were performed when outcomes were comparable. MAIN RESULTS: The meta-analyses included data from three randomized trials. Lower rates of SPTD before 34 weeks (relative risk 0.71, 95% confidence interval 0.53-0.95) and before 32 weeks (relative risk 0.62, 95% confidence interval 0.40-0.94) of pregnancy were observed among patients treated with vaginal progesterone. CONCLUSIONS: Vaginal progesterone and 17α-OHP were comparable for the prevention of recurrent SPTD in singleton pregnancies; vaginal progesterone could be superior.

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

BACKGROUND: 17-alpha Hydroxyprogesterone caproate for prevention of recurrent preterm birth is recommended for use in the United States. OBJECTIVE: 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. STUDY DESIGN: 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? RESULTS: 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). CONCLUSION: 17-alpha Hydroxyprogesterone caproate was ineffective for prevention of recurrent preterm birth and was associated with an increased rate of gestational diabetes.

The safety of progestogen in the prevention of preterm birth: meta-analysis of neonatal mortality.

BACKGROUND: The safety of preventive progestogen therapy for preterm birth remains to be established. This meta-analysis aimed to evaluate the effects of preventive progestogen therapy on neonatal mortality. METHODS: Randomized controlled trials (RCTs) on the preventive use of progestogen therapy, published between October 1971 and November 2015, were identified by searching MEDLINE/PubMed, EMBASE, Scopus, ClinicalTrials.gov, Cochrane Library databases, CINAHL, POPLINE, and LILACS using "progesterone" and "preterm birth" as key terms. We conducted separate analyses according to the type of progestogen administered and plurality of the pregnancy. RESULTS: Twenty-two RCTs provided data on 11,188 neonates. Preventive progestogen treatment in women with a history of preterm birth or short cervical length was not associated with increased risk of neonatal death compared to placebo in all analyzed progestogen types and pregnancy conditions. The pooled relative risks (95% confidence interval) of neonatal mortality were 0.69 (0.31-1.54) for vaginal progestogen in singleton pregnancies, 0.6 (0.33-1.09) for intramuscular progestogen in singleton pregnancies, 0.96 (0.51-1.8) for vaginal progestogen in multiple pregnancies, and 0.96 (0.49-1.9) for intramuscular progestogen in multiple pregnancies. CONCLUSIONS: The results of this meta-analysis suggest that administration of preventive progestogen treatment to women at risk for preterm birth does not appear to negatively affect neonatal mortality in single or multiple pregnancies regardless of the route of administration.

Vaginal progesterone vs intramuscular 17α-hydroxyprogesterone caproate for prevention of recurrent spontaneous preterm birth in singleton gestations: systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: Randomized controlled trials (RCTs) have recently compared intramuscular 17α-hydroxyprogesterone caproate (17-OHPC) with vaginal progesterone for reducing the risk of spontaneous preterm birth (SPTB) in singleton gestations with prior SPTB. The aim of this systematic review and meta-analysis was to evaluate the efficacy of vaginal progesterone compared with 17-OHPC in prevention of SPTB in singleton gestations with prior SPTB. METHODS: Searches of electronic databases were performed to identify all RCTs of asymptomatic singleton gestations with prior SPTB that were randomized to prophylactic treatment with either vaginal progesterone (intervention group) or intramuscular 17-OHPC (comparison group). No restrictions for language or geographic location were applied. The primary outcome was SPTB < 34 weeks. Secondary outcomes were SPTB < 37 weeks, < 32 weeks, < 28 weeks and < 24 weeks, maternal adverse drug reaction and neonatal outcomes. The summary measures were reported as relative risk (RR) with 95% CI. Risk of bias for each included study was assessed. RESULTS: Three RCTs (680 women) were included. The mean gestational age at randomization was about 16 weeks. Women were given progesterone until 36 weeks or delivery. Regarding vaginal progesterone, one study used 90 mg gel daily, one used 100 mg suppository daily and one used 200 mg suppository daily. All included RCTs used 250 mg intramuscular 17-OHPC weekly in the comparison group. Women who received vaginal progesterone had significantly lower rates of SPTB < 34 weeks (17.5% vs 25.0%; RR, 0.71 (95% CI, 0.53-0.95); low quality of evidence) and < 32 weeks (8.9% vs 14.5%; RR, 0.62 (95% CI, 0.40-0.94); low quality of evidence) compared with women who received 17-OHPC. There were no significant differences in the rates of SPTB < 37 weeks, < 28 weeks and < 24 weeks. The rate of women who reported adverse drug reactions was significantly lower in the vaginal progesterone group compared with the 17-OHPC group (7.1% vs 13.2%; RR, 0.53 (95% CI, 0.31-0.91); very low quality of evidence). Regarding neonatal outcomes, vaginal progesterone was associated with a lower rate of neonatal intensive care unit admission compared with 17-OHPC (18.7% vs 23.5%; RR, 0.63 (95% CI, 0.47-0.83); low quality of evidence). For the comparison of 17-OHPC vs vaginal progesterone, the quality of evidence was downgraded for all outcomes by at least one degree due to imprecision (the optimal information size was not reached) and by at least one degree due to indirectness (different interventions). CONCLUSIONS: Daily vaginal progesterone (either suppository or gel) started at about 16 weeks' gestation is a reasonable, if not better, alternative to weekly 17-OHPC injection for prevention of SPTB in women with singleton gestations and prior SPTB. However, the quality level of the summary estimates was low or very low as assessed by GRADE, indicating that the true effect may be, or is likely to be, substantially different from the estimate of the effect. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. COMPARACIÓN ENTRE LA PROGESTERONA VAGINAL Y EL 17Α-HIDROXIPROGESTERONA CAPROATO INTRAMUSCULAR PARA LA PREVENCIÓN DEL PARTO PRETÉRMINO ESPONTÁNEO RECURRENTE EN EMBARAZOS CON FETO ÚNICO: REVISIÓN SISTEMÁTICA Y METAANÁLISIS DE ENSAYOS CONTROLADOS ALEATORIOS: RESUMEN OBJETIVO: Recientemente se han realizado varios ensayos controlados aleatorios (ECA) que comparaban el caproato de 17α-hidroxiprogesterona (17-OHPC, por sus siglas en inglés) por vía intramuscular con la progesterona por vía vaginal para la reducción del riesgo de parto pretérmino espontáneo (PPTE) en embarazos con feto único de gestantes con historial de PPTE. El objetivo de esta revisión sistemática y metaanálisis fue evaluar la eficacia de la progesterona vaginal en comparación con la 17-OHPC en la prevención de embarazos con feto único de gestantes con historial de PPTE. MÉTODOS: Se realizaron búsquedas en bases de datos electrónicas para identificar todos los ECA con embarazos de feto único asintomáticos con historial de PPTE antes de ser asignados al azar a un tratamiento profiláctico, ya fuera con progesterona vaginal (grupo de intervención) o con 17-OHPC intramuscular (grupo de control). No se aplicaron restricciones respecto al idioma o la ubicación geográfica. El resultado primario fue PPTE < 34 semanas. Los resultados secundarios fueron PPTE <37 semanas, < 32 semanas, < 28 semanas y < 24 semanas, la reacción materna adversa al fármaco y los resultados neonatales. Las medidas del resumen se reportaron como riesgo relativo (RR) con IC del 95%. Para cada estudio incluido se evaluó el riesgo de sesgo. RESULTADOS: Se incluyeron tres ECA (680 mujeres). La media de la edad gestacional en el momento de la aleatorización fue de 16 semanas. A las mujeres se les administró progesterona hasta la semana 36 o hasta el parto. Con respecto a la progesterona vaginal, un estudio utilizó gel de 90 mg diariamente, otro utilizó un supositorio diario de 100 mg y el otro utilizó un supositorio diario de 200 mg. Todos los ECA incluidos en el grupo de comparación utilizaron 250 mg semanales de 17-OHPC por vía intramuscular. Las mujeres que recibieron progesterona vaginal tuvieron tasas significativamente más bajas de PPTE < 34 semanas (17,5% vs. 25,0%; RR 0,71 (IC 95%, 0,53-0,95); calidad de la evidencia baja) y < 32 semanas (8,9% vs. 14,5%; RR 0,62 (IC 95%, 0,40-0,94); calidad de evidencia baja), en comparación con las mujeres que recibieron 17-OHPC. No hubo diferencias significativas en las tasas de PPTE < 37 semanas, < 28 semanas y < 24 semanas. La tasa de mujeres que reportaron reacciones adversas a los medicamentos fue significativamente menor en el grupo de progesterona vaginal en comparación con el grupo de 17-OHPC (7,1% vs. 13,2%; RR 0,53 (IC 95%, 0,31-0,91); calidad de la evidencia muy baja). En cuanto a los resultados neonatales, la progesterona vaginal se asoció a una menor tasa de admisiones en la unidad neonatal de cuidados intensivos en comparación con la 17-OHPC (18,7% vs. 23,5%; RR 0,63 (IC 95%, 0,47-0,83); calidad de evidencia baja). Para la comparación del 17-OHPC con la progesterona vaginal se rebajó la calidad de las pruebas para todos los resultados en al menos un grado debido a imprecisiones (no se alcanzó el tamaño óptimo de la información) y en al menos un grado debido al carácter indirecto de los estudios (diferentes intervenciones). CONCLUSIONES: La progesterona vaginal administrada diariamente (ya fuera como supositorio o como gel) desde la semana 16 de gestación es una alternativa razonable, si no mejor, a una inyección semanal de 17-OHPC para la prevención de PPTE en mujeres con embarazos de feto único e historial de PPTE. Sin embargo, el nivel de calidad de las estimaciones del resumen fue bajo o muy bajo según lo evaluado por GRADE, lo que indica que el verdadero efecto puede ser, o es probable que sea, sustancialmente diferente de la estimación del efecto. 17Α-:META: : (randomized controlled trials,RCTs)(spontaneous preterm birth,SPTB)17α-(intramuscular 17α-hydroxyprogesterone caproate,17-OHPC)SPTB。metaSPTB17-OHPCSPTB。 : ,SPTBRCTs,RCTs()17-OHPC()。。34SPTB。37、32、2824SPTB,。(relative risk,RR)95%CI。。 : 3RCTs(680)。16。,36。,90 mg,100 mg,200 mg。,RCTs250 mg 17-OHPC。17-OHPC,34 [17.5%25.0%;RR,0.71(95% CI,0.53 ~ 0.95);]32[8.9%14.5%;RR,0.62(95% CI,0.40 ~ 0.94);]SPTB。37、2824SPTB。17-OHPC,[7.1%13.2%;RR,0.53(95% CI,0.31 ~ 0.91);]。,17-OHPC,[18.7%23.5%;RR,0.63(95% CI,0.47 ~ 0.83);]。17-OHPC,(),()。 : SPTBSPTB,16()17-OHPC,。,GRADE,,。.

Effect of partial compliance on the prevention of recurrent preterm birth in women receiving weekly 17 alpha-hydroxyprogesterone caproate injections.

PURPOSE: To analyze the effect of partial compliance on preterm birth (PTB) prevention among women with previous PTB and receiving 17 alpha-hydroxyprogesterone caproate (17-OHPC). STUDY DESIGN: This is a secondary analysis of a multicenter trial for the prevention of recurrent PTB. Women with prior PTB were randomly assigned between 15 0/7 and 20 3/7 weeks to weekly injections of either 17-OHPC or placebo. Full 100% compliance (group 1) was compared to 40-80% (group 2). Recurrent PTB rates and odds ratios were calculated. Student's t, Chi-square, Wilcoxon Rank-Sum, multivariate logistic regression and Breslow-Day tests were used. RESULTS: Group 1 included 370 women versus 35 in group 2. In each group, the PTB rate was significantly reduced in pregnancies receiving 17-OHPC compared to placebo. The adjusted odds ratio for PTB rate in group 1 was 0.48 (95% CI 0.31-0.75) versus 0.18 (95% CI 0.04-0.92) in group 2. Comparing the homogeneity of both odds ratios, the rates of recurrent PTB prevention in both groups were not statistically different (Breslow-Day test; p= .15). CONCLUSION: A compliance rate of 40-80% did not significantly reduce 17-OHPC's efficacy. If confirmed, our findings could lead to a dramatic decrease in costs related to prevention of recurrent PTB.

17-α Hydroxyprogesterone Caproate for the Prevention of Recurrent Preterm Birth: One Size May Not Fit All.

Spontaneous preterm birth is a syndrome with many causes and thus unresponsive to a single intervention. It logically follows that patients with a prior spontaneous preterm birth are a heterogeneous group unlikely to respond equally to a single preventive intervention such as 17-α hydroxyprogesterone caproate. Further confounding this issue is our fundamental lack of knowledge about the mechanism(s) by which 17-α hydroxyprogesterone caproate reduces preterm birth. Recently, studies demonstrating that responders and nonresponders can be identified based on obstetric history, genotype, physical characteristics, and behavioral factors have begun to provide clues into both 17-α hydroxyprogesterone caproate's mechanism and the pathophysiology of recurrent preterm birth and may allow for more targeted therapy. These studies lend support to speculation that inflammation or nitric oxide metabolism may be common threads between 17-α hydroxyprogesterone caproate's mechanism and preterm birth prevention. It will remain critically important to avoid the temptation to regard prior spontaneous preterm birth as a single disease entity amenable to a single treatment.

A randomized controlled trial of intramuscular versus vaginal progesterone for the prevention of recurrent preterm birth.

OBJECTIVE: To compare the efficacy of intramuscular hydroxyprogesterone caproate with that of vaginal progesterone for prevention of recurrent preterm birth. METHODS: A prospective randomized controlled trial was conducted at a US tertiary care center between June 1, 2007, and April 30, 2010. Women with singleton pregnancies (16-20 weeks) and a history of spontaneous preterm birth were randomly allocated using a computer-generated randomization sequence to receive either a weekly intramuscular injection of hydroxyprogesterone caproate (250 mg) or a daily vaginal progesterone suppository (100 mg). Participants, investigators, and assessors were not masked to group assignment. The primary outcome was birth before 37 weeks of pregnancy. Per-protocol analyses were performed: participants who completed follow-up were included. RESULTS: Analyses included 66 women given intramuscular progesterone and 79 given vaginal progesterone. Delivery before 37 weeks was recorded among 29 (43.9%) women in the intramuscular progesterone group and 30 (37.9%) in the vaginal progesterone group (P=0.50). CONCLUSION: Weekly intramuscular administration of hydroxyprogesterone caproate and daily vaginal administration of a progesterone suppository exhibited similar efficacy in reducing the rate of recurrent preterm birth. ClinicalTrials.gov: NCT00579553.

17-Hydroxyprogesterone caproate (17OHP-C) coverage among eligible women delivering at 2 North Carolina hospitals in 2012 and 2013: A retrospective cohort study.

BACKGROUND: Although a weekly injection of 17-hydroxyprogestone caproate is recommended for preventing recurrent preterm birth, clinical experience in North Carolina suggested that many eligible patients were not receiving the intervention. OBJECTIVE: Our study sought to assess how well practices delivering at 2 major hospitals were doing in providing access to 17-hydroxyprogesterone caproate treatment for eligible patients. STUDY DESIGN: This retrospective cohort analysis studied all deliveries occurring between January 1, 2012, and December 31, 2013, at 2 large hospitals in North Carolina. Women were included if they had a singleton pregnancy and history of a prior spontaneous preterm birth. We extracted demographic, payer, and medical information on each pregnancy, including whether women had been offered, accepted, and received 17-hydroxyprogesterone caproate. Our outcome of 17-hydroxyprogesterone caproate coverage was defined as documentation of ≥1 injection of the drug. RESULTS: Over the 2-year study period, 1216 women with history of a prior preterm birth delivered at the 2 study hospitals, of which 627 were eligible for 17-hydroxyprogesterone caproate eligible after medical record review. Only 296 of the 627 eligible women (47%; 95% confidence interval, 43-51%) received ≥1 dose of the drug. In multivariable analysis, hospital of delivery, later presentation for prenatal care, fewer prenatal visits, later gestation of prior preterm birth, and having had a term delivery immediately before the index pregnancy were all associated with failed coverage. Among those women who were "covered," the median number of 17-hydroxyprogesterone caproate injections was 9 (interquartile range, 4-15), with 84 of 296 charts (28%) not having complete information on the number of doses. CONCLUSION: Even under our liberal definition of coverage, less than half of eligible women received 17-hydroxyprogesterone caproate in this sample. Low overall use suggests that there is opportunity for improvement. Quality improvement strategies, including population-based measurement of 17-hydroxyprogesterone caproate coverage, are needed to fully implement this evidence-based intervention to decrease preterm birth.

Clinical Application of Progesterone for the Prevention of Preterm Birth, 2016.

While the preterm neonate continues to benefit from improved perinatal care, the rate of preterm birth in the United States remains significant. An increasing body of scientific literature has demonstrated the benefits of maternal progesterone administration in reducing primary and recurrent preterm birth. Intramuscular hydroxyprogesterone caproate is indicated in singleton pregnancies in women with a prior spontaneous preterm birth, while vaginal progesterone demonstrates similar efficacy in prolonging pregnancy in women with asymptomatic cervical shortening in the midtrimester. Given these favorable benefits, the use of progesterone has been expanded to other clinical situations at risk for preterm birth with less rigorous scientific evidence. This review highlights the current evidence-based clinical applications of progesterone for prevention of preterm birth.