Prevention of recurrent preterm delivery by 17 alpha-hydroxyprogesterone caproate

Assessing the applicability of obstetrical randomized controlled trials in real-world practices

This article examines the applicability of obstetrical randomized controlled trials (RCTs) in the real-world and proposes a classification of the value of these trials based on their potential for achieving sustainable practices. In the context of this discussion, real-world results pertain to the potential impact of the RCT on sustainable interventions and practices, and its implications for healthcare practice or policy, in the country (or countries) that was conducted. While RCTs are generally regarded as the gold standard of medical evidence, their effectiveness in producing meaningful real-world results depends, among various other factors, on the clarity and specificity of the trial definitions used for diagnosis (characteristics of the study group or enrollment criteria) and treatment (intervention). The definitions used for diagnosis and treatment, especially in pragmatic trials, can influence the likelihood for real-world implementation. By analyzing notable obstetrical RCTs, the authors find that trials with well-defined diagnoses and treatments that can be implemented without specialized expertise are more likely to generate results that are relevant to general practice, indicating higher value. In contrast, RCTs with ambiguous or undefined diagnoses and treatments often lead to variations in practice and produce unreliable real-world outcomes and practices suggesting lower value. Recognizing this variability can offer valuable guidance for the design and evaluation of RCTs in obstetrics.

The hormonal control of parturition

Parturition is a complex physiological process that must occur in a reliable manner and at an appropriate gestation stage to ensure a healthy newborn and mother. To this end, hormones that affect the function of the gravid uterus, especially progesterone (P4), 17β-estradiol (E2), oxytocin (OT), and prostaglandins (PGs), play pivotal roles. P4 via the nuclear P4 receptor (PR) promotes uterine quiescence and for most of pregnancy exerts a dominant block to labor. Loss of the P4 block to parturition in association with a gain in prolabor actions of E2 are key transitions in the hormonal cascade leading to parturition. P4 withdrawal can occur through various mechanisms depending on species and physiological context. Parturition in most species involves inflammation within the uterine tissues and especially at the maternal-fetal interface. Local PGs and other inflammatory mediators may initiate parturition by inducing P4 withdrawal. Withdrawal of the P4 block is coordinated with increased E2 actions to enhance uterotonic signals mediated by OT and PGs to promote uterine contractions, cervix softening, and membrane rupture, i.e., labor. This review examines recent advances in research to understand the hormonal control of parturition, with focus on the roles of P4, E2, PGs, OT, inflammatory cytokines, and placental peptide hormones together with evolutionary biology of and implications for clinical management of human parturition.

Developmental exposure to 17-α-hydroxyprogesterone caproate disrupts decision-making in adult female rats: A potential role for a dopaminergic mechanism

The synthetic progestin, 17α-hydroxyprogesterone caproate (17-OHPC), is administered to pregnant individuals at risk for preterm birth and is likely transferred from mother to fetus. Yet, there is little information regarding the potential effects of 17-OHPC administration on behavioral and neural development in offspring. In rats, neonatal 17-OHPC exposure altered dopaminergic fiber distribution and density in the prelimbic medial prefrontal cortex (mPFC) in neonates and adolescents, respectively. Additionally, neonatal 17-OHPC exposure in male rats increased response omissions in a delay discounting task of impulsive decision-making. Because developmental 17-OHPC exposure has differential effects in males and females, investigating the effects of 17-OHPC on impulsive decision-making in female rats is necessary. The present study tested the effects of developmental 17-OHPC exposure (P1-P14) in a delay discounting task in which female rats chose between a small immediate reward and a larger delayed (0, 15 30, or 45 s) reward. 17-OHPC-exposed females made more omissions than controls. There was no effect of 17-OHPC on large reward preference nor on response time, and omissions were similar during both free- and forced-choice trials. The present study also aimed to investigate the neural mechanisms underlying omissions in 17-OHPC-exposed female rats. The dopamine transporter inhibitor, methylphenidate (MPH), was administered prior to delay discounting testing. MPH treatment did not reduce omissions in 17-OHPC-exposed females. If anything, MPH increased omissions in control females nearly fourfold during the longest delays. These results suggest that developmental 17-OHPC exposure increased omissions without affecting impulsivity or slowing decision-making. Furthermore, omissions may be regulated, at least in part, by dopaminergic mechanisms.

Vaginal Progesterone to Prevent Spontaneous Preterm Birth in Women With a Sonographic Short Cervix: The Story of the PREGNANT Trial

The PREGNANT trial was a randomized, placebo-controlled, multicenter trial designed to determine the efficacy and safety of vaginal progesterone (VP) to reduce the risk of birth < 33 weeks and of neonatal complications in women with a sonographic short cervix (10 to 20 mm) in the mid-trimester (19 to 23 6/7 wk). Patients allocated to receive VP had a 45% lower rate of preterm birth (8.9% vs 16.1%; relative risk = 0.55; 95% CI: 0.33-0.92). Neonates born to mothers allocated to VP had a 60% reduction in the rate of respiratory distress syndrome. This article reviews the background, design, execution, interpretation, and impact of the PREGNANT Trial.

"Hypertension in Pregnancy Intervention Trial At Term" and "Disproportionate Intrauterine Growth Intervention Trial At Term" Studies

In 2003, in the context of a national research funding program in which obstetric research was prioritized, several perinatal centers took the initiative to jointly submit a number of applications to the subsidy programs of Effectiveness Research and Prevention of ZonMw. This has led to the funding of the Obstetric Consortium with several projects, including the "Hypertension in Pregnancy Intervention Trial At Term" and the "Disproportionate Intrauterine Growth Intervention Trial At Term" studies. The studies showed that induction of labor for hypertension and growth restriction at term was the appropriate management. Subsequent implementation improved maternal and perinatal outcomes.

Occurrence of ultrasonographic assessed placental abnormalities, treatments, pregnancy outcome, and subsequent fertility on a large warmblood stud farm: A retrospective field study

Little is known about the incidence and outcome of high-risk pregnancies in equine practice and clinical studies on spontaneous occurring placentitis cases and treatments are missing. Therefore, the aims of this retrospective field study were to (1) describe the incidence and severity of ultrasonographic assessed placental abnormalities (UPA) in 4,192 pregnancies on a large commercial warmblood stud farm in 2017 - 2019 and (2) characterize these UPA cases and their pregnancy outcome. UPA severity (Placental abnormality score (PSc) 1-3; low to high), nine treatment regimens (TM1-9) used in UPA cases and treatment duration as well as subsequent fertility were analyzed in the group of UPA mares. The proportion of pregnancies affected by UPA was 4.2 % (n=177/4192). Placental abnormality severity was scored as PSc1 (51.4 %), PSc2 (32.8 %) and PSc3 (15.8 %). The generalized mixed model revealed PSc was affected by mare age and mare status (own pregnancy (OP) or embryo transfer recipient (ER)) (P=0.035) with ER mares having increased PSc compared with mares having their own pregnancy. Abortion occurred in 17/177 (9.6 %) UPA pregnancies. Overall, at the end of the next season, 61.1 % of UPA mares were pregnant, 32.0 % barren, and 6.9 % open (n=175). Pregnancy was established in 62/91(68.1 %) of mares with PSc1, 31/58 (53.4 %) with PSc2 and 14/26 (53.8 %) with PSc3. Most pregnancies were achieved in the first 81/107 (75.7 %) or second 18/107 (16.8 %) inseminated cycle. In conclusion, early detection and treatment of ultrasonographic assessed placental abnormalities can save high-risk pregnancies in > 90 % of cases with a satisfying subsequent fertility.

Nationwide status of progestogen treatment to prevent spontaneous preterm birth: A questionnaire survey for childbirth healthcare facilities in Japan

AIM

This study aimed to investigate the current status of progestogen treatment for pregnant women at a high risk for preterm birth (PTB) in childbirth healthcare facilities in Japan.

METHODS

A web-based nationwide questionnaire survey regarding progestogen use for prevention of PTB was conducted among childbirth healthcare facilities from 2019 to 2021.

RESULTS

Valid responses were obtained from 528 facilities (25.2% of those surveyed), including 155 tertiary perinatal facilities (making up 92.3% of all tertiary perinatal care facilities). In the survey period, progestogen treatment was implemented in 207 facilities (39.2%) for PTB prevention. Regarding types of progestogens, 17α-hydroxyprogesterone caproate was used in 170 facilities (82.1%), with a low dose (125 mg/week) administered in 62.9% of the facilities to comply with the regulations of the national health insurance system, although 250 mg/week is considered the best dose. Vaginal progesterone was used in 36 facilities (17.4%), although the cost of vaginal progesterone was not covered by health insurance. Of the facilities not administering progestogen treatment, approximately 40% expressed that vaginal progesterone would be their first choice for PTB prevention in daily practice if it would be covered by health insurance in the future.

CONCLUSIONS

Due to the current regulations of the Japanese health insurance system, 17α-hydroxyprogesterone caproate, rather than vaginal progesterone, was mainly used for PTB prevention. Despite global evidence supporting vaginal progesterone as the approach with the highest efficacy, only a limited number of facilities have utilized it due to the current drug use regulations in Japan.

Does Antenatal Progesterone Administration Modify the Risk of Neonatal Intraventricular Hemorrhage?

OBJECTIVE

 Progesterone administration has been associated with improved neurological outcomes following traumatic brain injury in adults. However, studies examining the effect of progesterone on the risk of neonatal intraventricular hemorrhage (IVH) are inconsistent. We sought to determine if maternal administration of intramuscular 17-α-hydroxyprogesterone caproate (17-OHPC) is associated with decreased rates of IVH in infants born before 32-weeks gestation.

STUDY DESIGN

 This is a retrospective study of liveborn singleton deliveries between 20- and 32-weeks gestation at two large academic medical centers from January 1, 2012 to August 30, 2020. Data were extracted from hospital electronic medical record data warehouses using standardized definitions and billing and diagnosis codes. We evaluated receipt of 17-OHPC in the antepartum period and diagnosis of IVH (grade I-IV, per Volpe classification) during the neonatal delivery hospitalization encounter. Bivariate and multivariate analyses were performed to examine the association between 17-OHPC and neonatal IVH adjusting for potential confounders. Odds ratio (ORs) and 95% confidence intervals (CIs) were presented.

RESULTS

 Among 749 neonates born between 20- and 32-week gestation, 140 (18.7%) of their mothers had received antenatal 17-OHPC and 148 (19.8%) were diagnosed with IVH after birth. No significant association was observed between maternal 17-OHPC and neonatal IVH in unadjusted (OR 1.14, 95% CI 0.72-1.78) or adjusted analyses (adjusted odds ratio 1.14, 95% CI 0.71-1.84). Independent of exposure to 17-OHPC, as expected, infants born <28-weeks gestation or those with very low birthweight (<1,500 g) were at an increased risk of IVH (OR 2.32, 95% CI 1.55-3.48 and OR 2.19, 95% CI 1.09-4.38, respectively).

CONCLUSION

 Antenatal maternal 17-OHPC administration was not associated with the risk of neonatal IVH. Further research may be warranted to determine whether timing, route of delivery, and duration of progesterone therapy impact rates of neonatal IVH.

KEY POINTS

· This study aimed to compare the frequency of intraventricular hemorrhage in preterm neonates exposed to antenatal 17-α-hydroxyprogesterone caproate to those not exposed.. · In neonates born at <32-weeks gestation, maternal use of progesterone is not associated with the risk of intraventricular hemorrhage.. · In contrast to preclinical and adult data, this study suggests that progesterone exposure is not associated with the prevention of neonatal brain injury..

The dosing regimen for 17-hydroxyprogesterone caproate was suboptimal: lessons for future pharmacotherapy for pregnant women

BACKGROUND

Makena (17-hydroxyprogesterone caproate) was approved by the United States Food and Drug Administration for the prevention of recurrent spontaneous preterm birth in 2011 under the accelerated approval pathway, but fundamental pharmacokinetic or pharmacodynamic (Phase 1 and Phase 2) studies were not performed. At the time, there were no dose-response or concentration-response data. The therapeutic concentration was not known. The lack of such data brings into question the dosing regimen for 17-hydroxyprogesterone caproate and if it was optimized.

OBJECTIVE

The purpose of this study was to evaluate the dosing regimen for 17-hydroxyprogesterone by analyzing 3 data sets in which the 17-hydroxyprogesterone caproate pharmacology was evaluated, namely the Maternal-Fetal Medicine Omega 3 study, the Obstetric-Fetal Pharmacology Research Units study, and the Obstetrical-Fetal Pharmacology Research Centers study. If an inappropriate dosing regimen could be identified, such information could inform future studies of pharmacotherapy in pregnancy.

STUDY DESIGN

Data from the Omega 3 study were used to determine if plasma concentration was related to spontaneous preterm birth risk and if a threshold concentration could be identified. Data from the Obstetric-Fetal Pharmacology Research Units study were used to determine the half-life of 17-hydroxyprogesterone caproate and to develop a model to simulate drug concentrations with various dosing regimens. Data from the Obstetrical-Fetal Pharmacology Research Centers study were used to determine the relationship between dose and safety outcomes.

RESULTS

Analysis of the Omega 3 data set indicated that the risk for spontaneous preterm birth decreased as the log concentration of 17-hydroxyprogesterone caproate increased (odds ratio, 0.04; 95% confidence interval, 0.00-0.90). A steady state concentration of >9 ng/mL (equivalent to >8 ng/mL at 25-28 weeks) was associated with the lowest risk for spontaneous preterm birth (hazard ratio, 0.52; 95% confidence interval, 0.27-0.98; P=.04); this concentration was not achieved in 25% of subjects who received the 250 mg weekly dose. In the Obstetrical-Fetal Pharmacology Research Units study, the adjusted half-life (median and interquartile range) of 17-hydroxyprogesterone caproate was 14.0 (11.5-17.2) days. Simulations indicated that with the 250 mg weekly dose, >5 weekly injections were required to reach the 9 ng/mL target; however, those with the shortest half-life (corresponding to higher clearance), never reached the targeted 9 ng/mL concentration. In 75% of subjects, a loading dose of 500 mg weekly for 2 weeks followed by 250 mg weekly achieved and maintained the 9 ng/mL concentration within 2 weeks but in those 25% with the shortest half-life, concentrations exceeded the 9 ng/mL target for only 3 weeks. In the Obstetrical-Fetal Pharmacology Research Centers study, all 65 subjects who received a weekly dose of 500 mg exceeded the 9 ng/mL steady state.

CONCLUSION

The dosing regimen for 17-hydroxyprogesterone caproate was inadequate. There is a significant inverse relationship between drug concentration and spontaneous preterm birth. The risk was lowest when the concentration exceeded 9 ng/mL, but 25% of women who received the 250 mg weekly dose never reached or maintained this concentration. The drug's long half-life necessitates a loading dose to achieve therapeutic concentrations rapidly. The omission of basic pharmacologic studies to determine the proper dosing may have compromised the effectiveness of 17-hydroxyprogesterone caproate. Future pharmacotherapy trials in pregnancy must first complete fundamental pharmacology studies.

Progesterone therapy for prevention of recurrent spontaneous preterm birth in a minority patient population: a retrospective study

BACKGROUND

Preterm birth is a leading cause of infant morbidity and mortality worldwide. The burden of prematurity underscores the need for effective risk reduction strategies. The purpose of this study is to evaluate the efficacy of progesterone therapy, both intramuscular 17-α-hydroxyprogesterone caproate (IM 17-OHPC) and vaginal progesterone, in the prevention of recurrent spontaneous preterm birth (sPTB). The co-primary outcomes included: recurrent spontaneous PTB < 37 and < 34 weeks' gestation.

METHODS

This retrospective cohort study included 637 pregnant patients that delivered at any of the three hospitals within the Los Angeles County healthcare system between October 2015 and June 2021. We compared frequencies of measured variables between each of the progesterone treated groups to no treatment using Pearson chi-squared tests and independent t-tests for categorical and continuous variables, respectively. We estimated crude and adjusted associations between each specific treatment (versus no treatment) and primary outcomes using logistic regression.

RESULTS

Recurrent sPTB < 37 weeks' gestation occurred in 22.3% (n = 64) of those in the no treatment group, 29.1% (n = 86, p = .077) in the 17-OHPC group, and 14.3% (n = 6, p = 0.325) in the vaginal progesterone group. Recurrent sPTB < 34 weeks' gestation was 6.6% (n = 19) in the no treatment group, 11.8% (n = 35, p = .043) in the 17-OHPC group, and 7.1% (n = 3, p = 1) in the vaginal progesterone group. Among all participants, neither 17-OHPC nor vaginal progesterone was significantly associated with a reduction in recurrent sPTB at any time point. Among those with a short cervix, IM 17-OHPC was positively associated with recurrent sPTB < 37 weeks' gestation (aOR 5.61; 95% CI 1.16, 42.9).

CONCLUSIONS

Progesterone therapy of any type did not reduce the risk of recurrent sPTB < 34 or < 37 weeks' gestation compared to no progesterone therapy.

Randomized controlled trials: not always the "gold standard" for evidence in obstetrics and gynecology

Randomized controlled trials are considered the "gold standard" for therapeutic interventions, and it is not uncommon for sweeping changes in medical practice to follow positive results from such trials. However, randomized controlled trials are not without their limitations. Physicians frequently view randomized controlled trials as infallible, whereas they tend to dismiss evidence derived from sources other than randomized controlled trials as less credible or reliable. In several situations in obstetrics and gynecology, there are no randomized controlled trials to help guide the clinician. In these circumstances, it is important to evaluate the entire body of evidence including observational studies, rather than dismiss interventions altogether simply because no randomized controlled trials exist. Randomized controlled trials and observational studies should be viewed as complementary rather than at odds with each other. Some reversals in widely adopted clinical practice have recently been implemented following subsequent studies that contradicted the outcomes of major randomized controlled trials. The most notable of these was the withdrawal from the market of 17-hydroxyprogesterone caproate for preterm birth prevention. Such reversals could potentially have been averted if the inherent limitations of randomized controlled trials were carefully considered before implementing these universal practice changes. This Clinical Opinion underscores the limitations of an exclusive reliance on randomized controlled trials while disregarding other evidence in determining how best to care for patients. Solutions are proposed that advocate that clinicians adopt a more balanced perspective that considers the entirety of the available medical evidence and the individual patient characteristics, needs, and wishes.

Placental histology for targeted risk assessment of recurrent spontaneous preterm birth

BACKGROUND

Spontaneous preterm birth significantly increases the risk for a recurrent preterm birth. Only a few identifiable clinical risk factors can be referenced in counseling for recurrent preterm birth. Furthermore, treatment using progesterone supplementation has not consistently prevented preterm birth among high-risk patients, but it may be effective in a subset of those patients. Placental pathology from a previous pregnancy may be used to predict which patients will experience a recurrent preterm birth or to identify a subset of patients more likely to respond to treatment with antenatal progesterone.

OBJECTIVE

This study aimed to determine if histologic patterns are associated with recurrent preterm birth among patients with an index spontaneous preterm birth. A secondary objective was to determine if placental histologic types and/or progesterone receptor density in the decidua are associated with the response to progesterone supplementation with intramuscular 17-hydroxyprogesterone caproate.

STUDY DESIGN

This was a retrospective cohort study at a single institution of women with singleton pregnancies with an index spontaneous preterm birth and a subsequent birth within the same hospital system between 2009 and 2019. Patients were included if placental pathology was available for the index spontaneous preterm birth. A logistic regression was used to determine if there were independent associations between 4 histologic types (acute inflammation, maternal vascular malperfusion, fetal vascular malperfusion, chronic inflammation) and recurrent preterm birth. For the secondary endpoint, 17-hydroxyprogesterone caproate response was defined as prolonging gestation by >3 weeks beyond the gestational age at delivery in the index pregnancy. Patients who delivered <3 weeks beyond the gestational age in the index pregnancy but at ≥39 weeks' gestation were excluded. A logistic regression was used to assess the independent association between placental histology and 17-hydroxyprogesterone caproate response. Sensitivity analyses were completed using only patients with an index birth <36 weeks' gestation, and then excluding those with medically indicated preterm birth in a subsequent pregnancy. A nested case-control immunohistochemical study was done among 20 patients with a subsequent term birth and 20 patients with a subsequent spontaneous preterm birth. The percentage of cells in the maternal decidua positive for progesterone receptors was correlated with the subsequent pregnancy outcome.

RESULTS

A total of 352 patients were included. Acute inflammation was the most common histologic type seen among patients with spontaneous preterm birth (44.1%), followed by chronic inflammation (40.9%) and maternal vascular malperfusion (31.3%). No histologic type was independently associated with recurrent preterm birth. A total of 155 patients received 17-hydroxyprogesterone caproate in a second pregnancy. Low-grade acute inflammation was significantly associated with a decreased likelihood of 17-hydroxyprogesterone caproate response. Low-grade maternal vascular malperfusion among those with an index pregnancy delivered at <36 weeks' gestation was significantly associated with a more than 4 times increased likelihood of 17-hydroxyprogesterone caproate response when excluding those with a subsequent iatrogenic preterm birth. Progesterone receptor staining was not associated with recurrent preterm birth.

CONCLUSION

Although acute inflammation was prevalent among spontaneous preterm births, more than half of the spontaneous preterm births were not associated with acute inflammation. Low-grade acute inflammation was associated with a significantly decreased response to 17-hydroxyprogesterone caproate supplementation. Low-grade maternal vascular malperfusion was associated with a 4-fold increased likelihood of 17-hydroxyprogesterone caproate response among those with index deliveries <36 weeks' gestation. Further work is needed to determine if placental pathologic examination can be used to target treatment in subsequent pregnancies to prevent recurrent preterm birth.

Intestinal flora and pregnancy complications: Current insights and future prospects

Numerous studies have demonstrated the pivotal roles of intestinal microbiota in many physiopathological processes through complex interactions with the host. As a unique period in a woman's lifespan, pregnancy is characterized by changes in hormones, immunity, and metabolism. The gut microbiota also changes during this period and plays a crucial role in maintaining a healthy pregnancy. Consequently, anomalies in the composition and function of the gut microbiota, namely, gut microbiota dysbiosis, can predispose individuals to various pregnancy complications, posing substantial risks to both maternal and neonatal health. However, there are still many controversies in this field, such as "sterile womb" versus "in utero colonization." Therefore, a thorough understanding of the roles and mechanisms of gut microbiota in pregnancy and its complications is essential to safeguard the health of both mother and child. This review provides a comprehensive overview of the changes in gut microbiota during pregnancy, its abnormalities in common pregnancy complications, and potential etiological implications. It also explores the potential of gut microbiota in diagnosing and treating pregnancy complications and examines the possibility of gut-derived bacteria residing in the uterus/placenta. Our aim is to expand knowledge in maternal and infant health from the gut microbiota perspective, aiding in developing new preventive and therapeutic strategies for pregnancy complications based on intestinal microecology.

Cervical pessary versus vaginal progesterone in women with a singleton pregnancy, a short cervix, and no history of spontaneous preterm birth at less than 34 weeks' gestation: open label, multicentre, randomised, controlled trial

OBJECTIVE

To compare the effectiveness of cervical pessary and vaginal progesterone in the prevention of adverse perinatal outcomes and preterm birth in pregnant women of singletons with no prior spontaneous preterm birth at less than 34 weeks' gestation and who have a short cervix of 35 mm or less.

DESIGN

Open label, multicentre, randomised, controlled trial.

SETTING

20 hospitals and five obstetric ultrasound practices in the Netherlands.

PARTICIPANTS

Women with a healthy singleton pregnancy and an asymptomatic short cervix of 35 mm or less between 18 and 22 weeks' gestation were eligible. Exclusion criteria were prior spontaneous preterm birth at less than 34 weeks, a cerclage in situ, maternal age of younger than 18 years, major congenital abnormalities, prior participation in this trial, vaginal blood loss, contractions, cervical length of less than 2 mm or cervical dilatation of 3 cm or more. Sample size was set at 628 participants.

INTERVENTIONS

1:1 randomisation to an Arabin cervical pessary or vaginal progesterone 200 mg daily up to 36 weeks' of gestation or earlier in case of ruptured membranes, signs of infection, or preterm labour besides routine obstetric care.

MAIN OUTCOME MEASURES

Primary outcome was a composite adverse perinatal outcome. Secondary outcomes were rates of (spontaneous) preterm birth at less than 28, 32, 34, and 37 weeks. A predefined subgroup analysis was planned for cervical length of 25 mm or less.

RESULTS

From 1 July 2014 to 31 March 2022, 635 participants were randomly assigned to pessary (n=315) or to progesterone (n=320). 612 were included in the intention to treat analysis. The composite adverse perinatal outcome occurred in 19 (6%) of 303 participants with a pessary versus 17 (6%) of 309 in the progesterone group (crude relative risk 1.1 (95% confidence interval (CI) 0.60 to 2.2)). The rates of spontaneous preterm birth were not significantly different between groups. In the subgroup of cervical length of 25 mm or less, spontaneous preterm birth at less than 28 weeks occurred more often after pessary than after progesterone (10/62 (16%) v 3/69 (4%), relative risk 3.7 (95% CI 1.1 to 12.9)) and adverse perinatal outcomes seemed more frequent in the pessary group (15/62 (24%) v 8/69 (12%), relative risk 2.1 (0.95 to 4.6)).

CONCLUSIONS

In women with a singleton pregnancy with no prior spontaneous preterm birth at less than 34 weeks' gestation and with a midtrimester short cervix of 35 mm or less, pessary is not better than vaginal progesterone. In the subgroup of a cervical length of 25 mm or less, a pessary seemed less effective in preventing adverse outcomes. Overall, for women with single baby pregnancies, a short cervix, and no prior spontaneous preterm birth less than 34 weeks' gestation, superiority of a cervical pessary compared with vaginal progesterone to prevent preterm birth and consecutive adverse outcomes could not be proven.

TRIAL REGISTRATION

International Clinical Trial Registry Platform (ICTRP, EUCTR2013-002884-24-NL).

Management of a pregnant woman with a large cervical polyp and moderate genital bleeding in the first trimester

Polypectomy during pregnancy is known to be a risk for spontaneous late miscarriage or preterm delivery. We managed a pregnant woman in her 30s with a large cervical polyp without polypectomy, and we administered probiotics including Clostridium butyricum and 17-alpha-hydroxyprogesterone caproate. As a result, she delivered a healthy baby at 38 weeks.

Perinatal outcomes of emergency and elective cervical cerclages

Objective

This study aims to compare the perinatal outcomes of emergency and elective cervical cerclages.

Material and Methods

This retrospective study included a total of 247 patients, with a total of 142 emergency (with a history of mid-trimester miscarriage or vaginal delivery of < 34 weeks and cervical length < 25 mm) and 105 electives cerclage patients (with painless cervical dilation and cervical length <25 mm) who had cerclage with the vaginal cervical McDonald technique between 1.1.2017-1.10.2022. Pregnant women with normal screening tests at weeks 11-14, normal fetal morphology, and singleton pregnancies were included in the study. The study was conducted in a tertiary center providing NICU care for < 1500 g, less than 32 weeks of age, and on a mechanical ventilator. Obstetric and perinatal outcomes were reviewed.

Results

There was no statistical difference between the two groups regarding maternal age or BMI. It was observed that the week of delivery was greater for elective cerclages than for emergency cerclages (mean 34.6 GW versus 30.8 GW). The week of cerclage application was statistically higher in emergency cerclage (19.2 GW versus 16.3 GW p < 0.000). In addition, when we evaluated perinatal complications: prenatal Ex (n34 vs. n8 p < 0.001), C-reactive protein which is a marker of neonatal infection (12.7 mg/L vs. 2.5 mg/L p < 0.022), antibiotic use in the NICU (n 35 vs. n23 p < 0.050), the number of days of antibiotic use in the NICU (mean 15.3 days vs. 10.4 days p < 0.024), rate of NICU intubation (n 27 vs. n 11 p < 0.003), and neonatal sequelae (n 16 vs. n 6 p < 0.016) were significantly higher in the emergency cerclage group than in the elective cerclage group. There was no found significant difference between the progesterone given and not given progesterone after the procedure in term of the weeks of delivery (p < 0.810 emergency cervical cerclage; p < 0681 elective cervical cerclage).

Conclusion

Considering the available information, the results of elective cerclage seem to be more beneficial for the patient than those of emergency cerclage. Therefore, it would be more reasonable to perform elective cerclage in patients with mid-trimester or preterm miscarriage and concomitant cervical shortening before emergency cerclage is required. Furthermore, the benefit of progestin, in addition after surgical intervention, has not been established.

Effectiveness of 17-OHP for Prevention of Recurrent Preterm Birth: A Retrospective Cohort Study

OBJECTIVE

 17-α-hydroxyprogesterone caproate (17-OHP) has been recommended by professional societies for the prevention of recurrent preterm birth, but subsequent clinical studies have reported conflicting efficacy results. This study aimed to contribute to the evidence base regarding the effectiveness of 17-OHP in clinical practice using real-world data.

STUDY DESIGN

 A total of 4,422 individuals meeting inclusion criteria representing recurrent spontaneous preterm birth (sPTB) were identified in a database of insurance claims, and 568 (12.8%) received 17-OHP. Crude and propensity score-matched recurrence rates and risk ratios (RRs) for the association of receiving 17-OHP on recurrent sPTB were calculated.

RESULTS

 Raw sPTB recurrence rates were higher among those treated versus not treated; after propensity score matching, no association was detected (26.3 vs. 23.8%, RR = 1.1, 95% CI: 0.9-1.4).

CONCLUSION

 We failed to identify a beneficial effect of 17-OHP for the prevention of spontaneous recurrent preterm birth in our observational, U.S. based cohort.

KEY POINTS

· We observed higher risk for sPTB in the group receiving 17-OHP in the unmatched analysis. · After propensity-score matching, we still failed to identify a beneficial effect of 17-OHP on sPTB. · Sensitivity analyses demonstrated robustness to the inclusion criteria and modeling assumptions..

Challenges in Using Progestin to Prevent Singleton Preterm Births: Current Knowledge and Clinical Advice

Preterm birth is the leading cause of infant morbidity and mortality in children younger than 5 years old and accounts for approximately 35% of newborn deaths worldwide. The use of progestogen therapy for prevention of preterm birth has been one of the most controversial topics in modern obstetrics. Progestogens can be classified as natural or synthetic. Progesterone is a natural progestogen while progestins such as 17-alpha-hydroxyprogesterone caproate (17OHP-C) are synthetic steroid hormones. Evidence supporting the use of progestogens varies by formulation and populations studied. After more than a decade, the US Food and Drug Administration has withdrawn accelerated approval of 17OHP-C for the prevention of recurrent preterm birth in pregnant individuals with a singleton gestation. With this decision, there is no current FDA-approved treatment for prevention of spontaneous preterm birth. In this review, we provide a historical context behind the rise and fall of 17OHP-C clinical application, highlight the challenges behind the data supporting progestogen use, and offer suggestions on how to make an impact on preterm birth moving forward.

Integrative analysis of noncoding mutations identifies the druggable genome in preterm birth

Preterm birth affects ~10% of pregnancies in the US. Despite familial associations, identifying at-risk genetic loci has been challenging. We built deep learning and graphical models to score mutational effects at base resolution via integrating the pregnant myometrial epigenome and large-scale patient genomes with spontaneous preterm birth (sPTB) from European and African American cohorts. We uncovered previously unidentified sPTB genes that are involved in myometrial muscle relaxation and inflammatory responses and that are regulated by the progesterone receptor near labor onset. We studied genomic variants in these genes in our recruited pregnant women administered progestin prophylaxis. We observed that mutation burden in these genes was predictive of responses to progestin treatment for preterm birth. To advance therapeutic development, we screened ~4000 compounds, identified candidate molecules that affect our identified genes, and experimentally validated their therapeutic effects on regulating labor. Together, our integrative approach revealed the druggable genome in preterm birth and provided a generalizable framework for studying complex diseases.

Addressing a broken drug pipeline for preterm birth: why early preterm birth is an orphan disease

Preterm birth remains one of the most urgent unresolved medical problems in obstetrics, yet only 2 therapeutics for preventing preterm birth have ever been approved by the United States Food and Drug Administration, and neither remains on the market. The recent withdrawal of 17-hydroxyprogesterone caproate (17-OHPC, Makena) marks a new but familiar era for obstetrics with no Food and Drug Administration-approved pharmaceuticals to address preterm birth. The lack of pharmaceuticals reflects a broad and ineffective pipeline hindered by extensive regulatory hurdles, soaring costs of performing drug research, and concerns regarding adverse effects among a particularly vulnerable population. The pharmaceutical industry has historically limited investments in research for diseases with similarly small markets, such as cystic fibrosis, given their rarity and diminished projected financial return. The Orphan Drug Act, however, incentivizes drug development for "orphan diseases", defined as affecting <200,000 people in the United States annually. Although the total number of preterm births in the United States exceeds this threshold annually, the early subset of preterm birth (<34 weeks' gestation) would qualify, which is predominantly caused by inflammation and infection. The scientific rationale for classifying preterm birth into early and late subsets is strong given that their etiologies differ, and therapeutics that may be efficacious for one subset may not work for the other. For example, antiinflammatory therapeutics would be expected to be highly effective for early but not late preterm birth. A robust therapeutic pipeline of antiinflammatory drugs already exists, which could be used to target spontaneous early preterm birth, in combination with antibiotics shown to sterilize the amniotic cavity. New applications for therapeutics targeting spontaneous early preterm birth could categorize as orphan disease drugs, which could revitalize the preterm birth therapeutic pipeline. Herein, we describe why drugs targeting early preterm birth should qualify for orphan status, which may increase pharmaceutical interest for this vitally important obstetrical condition.

Eligibility, Utilization, and Effectiveness of 17-Alpha Hydroxyprogesterone Caproate in a Statewide Population-Based Cohort of Medicaid Enrollees

OBJECTIVE

The primary objective was to estimate the initiation and adherence rates of 17 α-hydroxyprogesterone caproate (17OHPC) among eligible mothers in a statewide population-based cohort of Medicaid enrollees. The secondary objectives were to (1) determine the association of maternal sociodemographic and clinical characteristics with 17OHPC utilization and (2) assess the real-world effectiveness of 17OHPC on recurrent preterm birth prevention and admission to neonatal intensive care unit (NICU).

STUDY DESIGN

This is a retrospective cohort study using a linked, longitudinal administrative dataset of birth certificates and medical assistance claims. Medicaid-enrolled mothers in Pennsylvania were included in this study if they had at least one singleton live birth from 2014 to 2016 following at least one spontaneous preterm birth. Maternal Medicaid claims were used to ascertain the use of 17OHPC from various manufacturers, including compounded formulations. Propensity score matching was used to create a covariate balance between 17OHPC treatment and comparison groups.

RESULTS

We identified 4,781 Medicaid-covered 17OHPC-eligible pregnancies from 2014 to 2016 in Pennsylvania, 3.4% of all Medicaid-covered singleton live births. The population-based initiation rate was 28.5% among eligible pregnancies. Among initiators, 50% received ≥16 doses as recommended, while 10% received a single dose only. The severity of previous spontaneous preterm birth was the strongest predictor for the initiation and adherence of 17OHPC. In the matched treatment (n = 1,210) and comparison groups (n = 1,210), we found no evidence of 17OHPC effectiveness. The risks of recurrent preterm birth (relative risk [RR] 1.10, 95% confidence interval [CI] 0.97-1.24) and births admitted to NICU (RR 1.00, 95% CI 0.84-1.18) were similar in treated and comparison mothers.

CONCLUSION

The 17OHPC-eligible population represented 3.4% of singleton live births. Less than one-third of eligible mothers initiated treatment. Among initiators, 50% were treatment adherent. We found no difference in the risk of recurrent preterm birth or admission to NICU between treatment and comparison groups.

KEY POINTS

· About 3.4% of singleton live births were eligible for 17OHPC.. · About 30% of eligible mothers initiated treatment.. · We found no association of 17OHPC with recurrent preterm birth..

Progesterone control of myometrial contractility

During pregnancy, the primary function of the uterus is to be quiescent and not contract, which allows the growing fetus to develop and mature. A uterine muscle layer, myometrium, is composed of smooth muscle cells (SMCs). Before the onset of labor contractions, the uterine SMCs experience a complex biochemical and molecular transformation involving the expression of contraction-associated proteins. Labor is initiated when genes in SMCs are activated in response to a combination of hormonal, inflammatory and mechanical signals. In this review, we provide an overview of molecular mechanisms regulating the process of parturition in humans, focusing on the hormonal control of the myometrium, particularly the steroid hormone progesterone. The primary reason for discussing the regulation of myometrial contractility by progesterone is the importance of the clinical problem of preterm birth. It is thought that the hormonal mechanisms regulating premature uterine contractions represent an untimely triggering of the normal events occurring during term parturition. Yet, our knowledge of the complex and redundant hormonal pathways controlling uterine contractile activity leading to delivery of the neonate remains incomplete. Finally, we introduce recent animal studies using a novel class of drugs, Selective Progesterone Receptor Modulators, targeting progesterone signaling to prevent premature myometrial contractions.

Association between the duration of progesterone supplementation treatment and premature neonates outcomes: A retrospective cohort study

Background and Aims

Preterm birth (PTB) is the leading cause of perinatal mortality and morbidity, progesterone is one of the main hormones to maintain a normal pregnancy. However, there are still conflicting results regarding using progesterone supplementation to prevent PTB and improve neonatal outcomes. The length of treatment with progesterone supplementation is also one of the challenges ahead, so the present study was conducted to investigate the relationship between the duration of progesterone supplementation treatment and neonatal outcomes.

Methods

This retrospective cohort study was conducted on pregnant women at risk of PTB and who have taken progesterone supplementation. They were asked about the length of treatment with progesterone supplements and finally, the neonatal outcomes of these women were measured.

Results

A total of 265 pregnant women who met the inclusion criteria were included in this study and the subjects were divided into two groups that received progesterone <12 weeks and received progesterone ≥12. In the group of women receiving progesterone with a treatment duration of ≥12 weeks, the rate of preterm labor, respiratory distress syndrome, low birth weight, and the need for hospitalization were significantly lower than in the group receiving progesterone with a treatment duration of ≥12 weeks.

Conclusion

Progesterone administration for longer than 12 weeks in women at risk of PTB can improve neonatal outcomes.

A Comparison of Vaginal and Intramuscular Progesterone for the Prevention of Recurrent Preterm Birth

OBJECTIVE

This study aimed to examine whether vaginal progesterone is noninferior to 17-α hydroxyprogesterone caproate (17OHP-C) in the prevention of recurrent preterm birth (PTB).

STUDY DESIGN

This retrospective cohort study included singleton pregnancies among women with a history of spontaneous PTB who received prenatal care at a single tertiary center from 2011 to 2016. Pregnancies were excluded if progesterone was not initiated prior to 24 weeks or the fetus had a major congenital anomaly. The primary outcome was PTB <37 weeks. A priori, noninferiority was to be established if the upper bound of the adjusted two-sided 90% confidence interval (CI) for the difference in PTB fell below 9%. Inverse probability of treatment weighting (IPTW) was used to carefully control for confounding associated with choice of treatment and PTB. Adjusted differences in PTB proportions were estimated via IPTW regression, with standard errors adjustment for multiple pregnancies per woman. Secondary outcomes included PTB <34 and <28 weeks, spontaneous PTB, neonatal intensive care unit admission, and gestational age at delivery.

RESULTS

Among 858 pregnancies, 41% (n = 353) received vaginal progesterone and 59% (n = 505) were given 17OHP-C. Vaginal progesterone use was more common later in the study period, and among women who established prenatal care later, had prior PTBs at later gestational ages, and whose race/ethnicity was neither non-Hispanic white nor non-Hispanic Black. Vaginal progesterone did not meet noninferiority criteria compared with 17-OHPC in examining PTB <37 weeks, with an IPTW adjusted difference of 3.4% (90% CI: -3.5, 10.3). For secondary outcomes, IPTW adjusted differences between treatment groups were generally small and CIs were wide.

CONCLUSION

We could not conclude noninferiority of vaginal progesterone to 17OHP-C; however, women and providers may be willing to accept a larger difference (>9%) when considering the cost and availability of vaginal progesterone versus 17OHP-C. A well-designed randomized trial is needed.

KEY POINTS

· Vaginal progesterone is not noninferior to 17OHP-C.. · PTB risk may be 10% higher with vaginal progesterone.. · Associations did not differ based on obesity status..

Changes in use of 17-OHPC after the PROLONG trial: a physician survey

OBJECTIVES

To determine if 17α-hydroxyprogesterone caproate (17OHPC) or vaginal progesterone use for patients at risk for preterm birth has changed since the publication of the 17-OHPC to Prevent Recurrent Preterm Birth in Singleton Gestations (PROLONG) trial, and to assess which organizations' (Food and Drug Administration's [FDA], American College of Obstetrics and Gynecology's [ACOG] or Society of Maternal Fetal Medicine's [SMFM]) statements most influenced change.

METHODS

Through a vignette-based physician survey, we sought to measure (by Likert scale) how counseling tendencies regarding 17OHPC and vaginal progesterone have changed since the PROLONG trial publication. Participants were also asked which organizations' statements most influenced change.

RESULTS

With response rate of 97 % (141/145), a pre-to-post PROLONG trial comparison revealed significant changes in counseling for progesterone. Respondents were less likely to recommend 17OHPC (p<0.001) and more likely to recommend vaginal (p<0.001). The FDA statement most influenced the decision not to recommend 17OHPC for the prevention of preterm birth (r=-0.23, p=0.005).

CONCLUSIONS

Providers have made significant changes in their counseling regarding progesterone use for patients at risk for preterm birth after the publication of the PRLONG trial.

Metabolomic profiling of preterm birth in pregnant women living with HIV

BACKGROUND

Preterm birth is a leading cause of death in children under the age of five. The risk of preterm birth is increased by maternal HIV infection as well as by certain antiretroviral regimens, leading to a disproportionate burden on low- and medium-income settings where HIV is most prevalent. Despite decades of research, the mechanisms underlying spontaneous preterm birth, particularly in resource limited areas with high HIV infection rates, are still poorly understood and accurate prediction and therapeutic intervention remain elusive.

OBJECTIVES

Metabolomics was utilized to identify profiles of preterm birth among pregnant women living with HIV on two different antiretroviral therapy (ART) regimens.

METHODS

This pilot study comprised 100 mother-infant dyads prior to antiretroviral initiation, on zidovudine monotherapy or on protease inhibitor-based antiretroviral therapy. Pregnancies that resulted in preterm births were matched 1:1 with controls by gestational age at time of sample collection. Maternal plasma and blood spots at 23-35 weeks gestation and infant dried blood spots at birth, were assayed using an untargeted metabolomics method. Linear regression and random forests classification models were used to identify shared and treatment-specific markers of preterm birth.

RESULTS

Classification models for preterm birth achieved accuracies of 95.5%, 95.7%, and 80.7% in the untreated, zidovudine monotherapy, and protease inhibitor-based treatment groups, respectively. Urate, methionine sulfone, cortisone, and 17α-hydroxypregnanolone glucuronide were identified as shared markers of preterm birth. Other compounds including hippurate and N-acetyl-1-methylhistidine were found to be significantly altered in a treatment-specific context.

CONCLUSION

This study identified previously known as well as novel metabolomic features of preterm birth in pregnant women living with HIV. Validation of these models in a larger, independent cohort is necessary to ascertain whether they can be utilized to predict preterm birth during a stage of gestation that allows for therapeutic intervention or more effective resource allocation.

Progestogen maintenance therapy for prolongation of pregnancy after an episode of preterm labour: A systematic review and meta-analysis

BACKGROUND

Evidence for progestogen maintenance therapy after an episode of preterm labour (PTL) is contradictory.

OBJECTIVES

To assess effectiveness of progestogen maintenance therapy after an episode of PTL.

SEARCH STRATEGY

An electronic search in Central Cochrane, Ovid Embase, Ovid Medline and clinical trial databases was performed.

SELECTION CRITERIA

Randomised controlled trials (RCT) investigating women between 16+0 and 37+0  weeks of gestation with an episode of PTL who were treated with progestogen maintenance therapy compared with a control group.

DATA COLLECTION AND ANALYSIS

Systematic review and meta-analysis were conducted. The primary outcome was latency time in days. Secondary neonatal and maternal outcomes are consistent with the core outcome set for preterm birth studies. Studies were extensively assessed for data trustworthiness (integrity) and risk of bias.

MAIN RESULTS

Thirteen RCT (1722 women) were included. Progestogen maintenance therapy demonstrated a longer latency time of 4.32 days compared with controls (mean difference [MD] 4.32, 95% CI 0.40-8.24) and neonates were born with a higher birthweight (MD 124.25 g, 95% CI 8.99-239.51). No differences were found for other perinatal outcomes. However, when analysing studies with low risk of bias only (five RCT, 591 women), a significantly longer latency time could not be shown (MD 2.44 days; 95% CI -4.55 to 9.42).

CONCLUSIONS

Progestogen maintenance therapy after PTL might have a modest effect on prolongation of latency time. When analysing low risk of bias studies only, this effect was not demonstrated. Validation through further research, preferably by an individual patient data meta-analysis is highly recommended.

Vaginal progesterone for the prevention of recurrent spontaneous preterm birth

After the United States Food and Drug Administration pulled 17-alpha hydroxyprogesterone caproate from the market for its use in prevention of recurrent spontaneous preterm birth, national societies have had mixed recommendations regarding the management of patients with a singleton pregnancy and previous spontaneous preterm birth. Herein we highlight the randomized trial data and translational evidence supporting the use of vaginal progesterone for prevention of recurrent spontaneous preterm birth in singleton pregnancies. Prophylactic vaginal progesterone starting at 16 weeks and 0 days every night should be offered to patients with singletons and previous singleton spontaneous preterm birth regardless of cervical length, and continued along with placement of cerclage if a transvaginal ultrasound cervical length ≤25 mm is detected at <24 weeks.

What now? A critical evaluation of over 20 years of clinical and research experience with 17-alpha hydroxyprogesterone caproate for recurrent preterm birth prevention

Spontaneous preterm birth is multifactorial, and underlying etiologies remain incompletely understood. Supplementation with progestogens, including 17-alpha hydroxyprogesterone caproate has been a mainstay of prematurity prevention strategies in the United States in the last 2 decades. Following a recent negative confirmatory trial, 17-alpha hydroxyprogesterone caproate was withdrawn from the US market and is currently available only through clinical research studies. This expert review summarized clinical and research data regarding the use of 17-alpha hydroxyprogesterone caproate in the United States from 2003 to 2023 for recurrent prematurity prevention. In 17-alpha hydroxyprogesterone caproate. The history of the use, mechanisms of action, clinical trial results, and efficacy by clinical and biologic criteria of 17-alpha hydroxyprogesterone caproate are presented. We report that disparate findings and conclusions between similarly designed rigorous studies may reflect differences in a priori risk and population incidence and extreme care should be taken in interpreting the studies and making decisions regarding efficacy of 17-alpha hydroxyprogesterone caproate for the prevention of preterm birth. The likelihood of improved obstetrical outcomes after receiving 17-alpha hydroxyprogesterone caproate may vary by clinical factors (eg, body mass index), plasma drug concentrations, and genetic factors, although the identification of individuals most likely to benefit remains imperfect. It is crucial for the medical community to recognize the importance of preserving the decades-long efforts invested in preventing recurrent preterm birth in the United States. Moreover, it is important that we thoroughly and thoughtfully evaluate 17-alpha hydroxyprogesterone caproate as a promising contender for future well-executed prematurity studies.

Progesterone modulates extracellular heat-shock proteins and interlukin-1β in human choriodecidual after Escherichia coli infection

INTRODUCTION

Chorioamnionitis is an adverse condition in human pregnancy caused by many bacterial pathogens including Escherichia coli (E. coli); which has been associated with higher risk of preterm birth. We recently reported that human maternal decidua (MDec) tissue responds to E. coli infection by secreting extracellular heat-shock proteins (eHsp)-60, -70 and interlukin-1β (IL-1β). Previous studies have shown that progesterone (P4) regulates the immune response, but it is unknown whether P4 inhibits the secretion of eHsp. The aim of this investigation was to determine the role of P4 on the secretion of eHsp-27, -60, -70 and IL-1β in MDec after 3, 6, and 24 h of E. coli infection.

METHODS

Nine human feto-maternal interface (HFMi) tissues were included and mounted in the Transwell culture system. Only the maternal decidua (MDec) was stimulated for 3, 6 and 24 h with E. coli alone or in combination with progesterone and RU486. After each treatment, the HFMi tissue was recovered to determine histological changes and the culture medium recovered to evaluate the levels of eHsp-27, -60, -70 and IL-1β by ELISA and mRNA expression by RT-PCR.

RESULTS

No structural changes were observed in the HFMi tissue treated with P4 and RU486. However, stimulation with E. coli produces diffuse inflammation and ischemic necrosis. E. coli induced infection decreases, in time- and dose-dependent manner, eHsp-27 and increases eHsp-60, eHsp-70 and IL-1β levels. In contrast, incubation of HFMi tissue with E. coli + P4 reversed eHsp and IL-1β secretion levels relative to E. coli stimulation group but not relative to the control group. The same profile was observed on the expression of eHsp-27 and eHsp-60.

DISCUSSION

we found that progesterone modulates the anti-inflammatory (eHsp-27) and pro-inflammatory (eHsp-60 and eHsp-70) levels of eHsp induced by E. coli infection in human choriodecidual tissue. eHsp-60 and eHsp-70 levels were not completely reversed; maintaining the secretion of IL-1β, which has been associated with adverse events during pregnancy.

A Possible Mechanism of Action of 17α-Hydroxyprogesterone Caproate: Enhanced IL-10 Production

OBJECTIVE

The rate of recurrent spontaneous preterm birth (PTB) was reduced by 33% in the Maternal-Fetal Medicine Unit (MFMU) Network trial of 17α-hydroxyprogesterone caproate (17-OHPC), but the mechanism of action, 17 years later, remains elusive. The robustness of the interleukin-10 (IL-10) response to lipopolysaccharide (LPS) stimulation of leukocytes in pregnant women with a prior PTB correlates with gestational age at delivery. This study sought to determine if there is a relationship between the concentration of 17-OHPC and response to LPS stimulation.

STUDY DESIGN

We performed a secondary analysis of data from the Omega-3 MFMU trial which evaluated the effectiveness of omega-3 fatty acid supplementation in reducing recurrent PTB. We utilized previously characterized data from a subanalyses of the Omega-3 trial of IL-10 and tumor necrosis factor alpha (TNF-α) levels from peripheral blood mononuclear cells stimulated with LPS. Blood was obtained from enrolled women at 16 to 22 weeks' gestation (baseline) and 25 to 28 weeks' gestation (posttreatment). All women received 17-OHPC and plasma 17-OHPC concentrations were measured at 25 to 28 weeks' gestation. We analyzed these data to determine if there was a relationship between 17-OHPC concentration and cytokine production. We then performed an in vitro study to determine if 17-OHPC could directly alter cytokine production by THP-1-derived macrophages.

RESULTS

In the clinical samples, we found that 17-OHPC plasma concentrations were correlated with the quantity of the LPS-stimulated production of IL-10. TNF-α production after LPS stimulation was unrelated to 17-OHPC concentration. In the in vitro study, we demonstrate a 17-OHPC concentration dependent increase in IL-10 production.

CONCLUSION

In women receiving 17-OHPC for PTB prevention, we demonstrate a relationship between plasma 17-OHPC and LPS-stimulated IL-10 production by circulating leukocytes. We also demonstrate that, in vitro, 17-OHPC treatment affects IL-10 production by LPS-stimulated macrophages. Collectively, these findings support an immunomodulatory mechanism of action of 17-OHPC in the prevention of recurrent PTB.

KEY POINTS

· 17-OHPC plasma concentrations and LPS-stimulated IL-10 levels correlate in clinical samples in women at risk for recurrent preterm birth.. · 17-OHPC can modulate the response of LPS-stimulated macrophages to increase IL-10 production.. · There was no relationship between TNF-α and plasma concentration of 17-OHPC in clinical samples or in vitro..

Rematching on-the-fly: Sequential matched randomization and a case for covariate-adjusted randomization

Covariate-adjusted randomization (CAR) can reduce the risk of covariate imbalance and, when accounted for in analysis, increase the power of a trial. Despite CAR advances, stratified randomization remains the most common CAR method. Matched randomization (MR) randomizes treatment assignment within optimally identified matched pairs based on covariates and a distance matrix. When participants enroll sequentially, sequentially matched randomization (SMR) randomizes within matches found "on-the-fly" to meet a pre-specified matching threshold. However, pre-specifying the ideal threshold can be challenging and SMR yields less-optimal matches than MR. We extend SMR to allow multiple participants to be randomized simultaneously, to use a dynamic threshold, and to allow matches to break and rematch if a better match later enrolls (sequential rematched randomization; SRR). In simplified settings and a real-world application, we assess whether these extensions improve covariate balance, estimator/study efficiency, and optimality of matches. We investigate whether adjusting for more covariates can be detrimental upon covariate balance and efficiency as is the case of traditional stratified randomization. As secondary objectives, we use the case study to assess how SMR schemes compare side-by-side with common and related CAR schemes and whether adjusting for covariates in the design can be as powerful as adjusting for covariates in a parametric model. We find each SMR extension, individually and collectively, to improve covariate balance, estimator efficiency, study power, and quality of matches. We provide a case-study where CAR schemes with randomization-based inference can be as and more powerful than non-CAR schemes with parametric adjustment for covariates.

A dual-binding magnetic immunoassay to predict spontaneous preterm birth

Complications posed by preterm birth (delivery before 37 weeks of pregnancy) are a leading cause of newborn morbidity and mortality. The previous discovery and validation of an algorithm that includes maternal serum protein biomarkers, sex hormone-binding globulin (SHBG), and insulin-like growth factor-binding protein 4 (IBP4), with clinical factors to predict preterm birth represents an opportunity for the development of a widely accessible point-of-care assay to guide clinical management. Toward this end, we developed SHBG and IBP4 quantification assays for maternal serum using giant magnetoresistive (GMR) sensors and a self-normalizing dual-binding magnetic immunoassay. The assays have a picomolar limit of detections (LOD) with a relatively broad dynamic range that covers the physiological level of the analytes as they change throughout gestation. Measurement of serum from pregnant donors using the GMR assays was highly concordant with those obtained using a clinical mass spectrometry (MS)-based assay for the same protein markers. The MS assay requires capitally intense equipment and highly trained operators with a few days turnaround time, whereas the GMR assays can be performed in minutes on small, inexpensive instruments with minimal personnel training and microfluidic automation. The potential for high sensitivity, accuracy, and speed of the GMR assays, along with low equipment and personnel requirements, make them good candidates for developing point-of-care tests. Rapid turnaround risk assessment for preterm birth would enable patient testing and counseling at the same clinic visit, thereby increasing the timeliness of recommended interventions.

Reassessing Preterm Birth Prevention After the Withdrawal of 17-α Hydroxyprogesterone Caproate

The U.S. Food and Drug Administration has recently withdrawn approval for 17-α hydroxyprogesterone caproate for prevention of recurrent preterm birth, and recent studies have called into question benefits of the pessary in the setting of a short cervix. Obstetric health care professionals are once again left with limited remaining options for preterm birth prevention. This narrative review summarizes the best current evidence on the use of vaginal progesterone, low-dose aspirin, and cerclage for the prevention of preterm birth; attempts to distill possible lessons learned from studies of progesterone and pessary, as well as their implementation into practice; and highlights areas where inroads into preterm birth prevention may be possible outside of the progesterone-aspirin-cerclage paradigm.

Preeclampsia and the Antiphospholipid Syndrome

Antiphospholipid syndrome (APS) is characterized by venous or arterial thrombosis and/or adverse pregnancy outcome in the presence of persistent laboratory evidence of antiphospholipid antibodies (aPLs). Preeclampsia complicates about 10-17% of pregnancies with APS. However, only early onset preeclampsia (<34 weeks of gestation) belongs to the clinical criteria of APS. The similarities in the pathophysiology of early onset preeclampsia and APS emphasize an association of these two syndromes. Overall, both are the result of a defective trophoblast invasion and decidual transformation at early gestation. Women with APS are at increased risk for prematurity; the reasons are mostly iatrogenic due to placental dysfunction, such as preeclampsia or FGR. Interestingly, women with APS have also an increased risk for preterm delivery, even in the absence of FGR and preeclampsia, and therefore it is not indicated but spontaneous. The basic treatment of APS in pregnancy is low-dose aspirin and low-molecular-weight heparin. Nevertheless, up to 20-30% of women develop complications at early and late gestation, despite basic treatment. Several additional treatment options have been proposed, with hydroxychloroquine (HCQ) being one of the most efficient. Additionally, nutritional interventions, such as intake of vitamin D, have shown promising beneficial effects. Curcumin, due to its antioxidant and anti-inflammatory properties, might be considered as an additional intervention as well.

New Interpretation of Neonatal Outcomes by Phenotypically Classified Preterm Syndrome: A Retrospective Cohort Study

OBJECTIVE

The global aim to lower preterm birth rates has been hampered by the insufficient and incomplete understanding of its etiology, classification, and diagnosis. This study was designed to evaluate the association of phenotypically classified preterm syndromes with neonatal outcomes; to what extent would these outcomes be modified after the obstetric interventions, including use of glucocorticoid, magnesium sulfate, and progesterone.

METHODS

This was a retrospective cohort study conducted at Tongji Hospital (composed of Main Branch, Optical Valley Branch and Sino-French New City Branch) in Wuhan. A total of 900 pregnant women and 1064 neonates were retrospectively enrolled. The outcomes were the distribution of different phenotypes among parturition signs and pathway to delivery, the association of phenotypically classified clusters with short-term unfavorable neonatal outcomes, and to what extent these outcomes could be modified by obstetric interventions.

RESULTS

Eight clusters were identified using two-step cluster analysis, including premature rupture of fetal membranes (PPROM) phenotype, abnormal amniotic fluid (AF) phenotype, placenta previa phenotype, mixed condition phenotype, fetal distress phenotype, preeclampsia-eclampsia & hemolysis, elevated liver enzymes, and low platelets syndrome (PE-E&HELLP) phenotype, multiple fetus phenotype, and no main condition phenotype. Except for no main condition phenotype, the other phenotypes were associated with one or more complications, which conforms to the clinical practice. Compared with no main condition phenotype, some phenotypes were significantly associated with short-term adverse neonatal outcomes. Abnormal AF phenotype, mixed condition phenotype, PE-E&HELLP phenotype, and multiple fetus phenotype were risk factors for neonatal small-for gestation age (SGA); placenta previa phenotype was not associated with adverse outcomes except low APGAR score being 0-7 at one min; mixed condition phenotype was associated with low APGAR scores, SGA, mechanical ventilation, and grade HI-W intraventricular hemorrhage (IVH); fetal distress phenotype was frequently associated with neonatal SGA and mechanical ventilation; PE-E&HELLP phenotype was correlated with low APGAR score being 0-7 at one min, SGA and neonatal intensive care unit (NICU) admission; multiple fetus phenotype was not a risk factor for the outcomes included except for SGA. Not all neonates benefited from obstetric interventions included in this study.

CONCLUSION

Our research disclosed the independent risk of different preterm phenotypes for adverse pregnancy outcomes. This study is devoted to putting forward the paradigm of classifying preterm birth phenotypically, with the ultimate purpose of defining preterm phenotypes based on multi-center studies and diving into the underlying mechanisms.

The association between maternal anemia during pregnancy and preterm birth

BACKGROUND & AIMS

Maternal anemia is one of the most serious health problems during pregnancy. The causes of anemia include iron deficiency, parasitic diseases, micronutrient deficiencies, and hereditary hemoglobinopathies. Because the reported association between maternal anemia and preterm labor in different studies is varied depending on the month of pregnancy this study aims to determine this relationship after adjustment for potential confounders.

METHODS

A case-control study was conducted among 801 pregnant women (267 cases and 534 controls) in Sardashat, Iran from October 2012 to October 2013. Hemoglobin (Hb) values were measured for all women participating in the study during the first and second trimesters of pregnancy, and the average Hb values were presented. Statistical analyzes were performed with logistic regression.

RESULTS

The mean age of participants was 26.4 ± 5.25 years for the case group and 27.2 ± 6.51 years for the control group. Preterm birth was associated with maternal anemia during pregnancy [aOR = 2.69 (95% CI; 1.46 to 4.95)] even after adjusting for confounding effects including maternal age, history of abortion [aOR = 2.41 (95% CI; 1.42 to 4.08)], history of preterm birth [aOR = 11.38 (95% CI; 3.48 to 37.22)], obesity (aOR: 3.441; CI95%: 1.18-10.06), parity [aOR = 0.42 (95% CI; 0.25 to 0.69)], preeclampsia/eclampsia [aOR = 6.08 (95% CI; 2.64 to 14)], and GDM [aOR = 4.80 (95% CI; 2.02 to 11.41)]).

CONCLUSION

Early detection and adequate treatment of anemia during pregnancy can help reduce the prevalence of preterm birth.

Progesterone-mediated reversal of mifepristone-induced pregnancy termination in a rat model: an exploratory investigation

Globally, a substantial proportion of pregnancies end in induced (particularly medication) abortion. However, data also indicates a percentage of women who seek assistance in potentially reversing the medication abortion process. While previous literature has suggested the potential for progesterone-mediated reversal of mifepristone-induced abortion, this process has not been effectively investigated pre-clinically. Our study explored the potential reversal of mifepristone-induced pregnancy termination using progesterone in a rat model, following a clear initiation of pregnancy termination. Female Long-Evans rats were divided into three groups (n = 10-16/group): Pregnant control (M-P-), mifepristone-only/pregnancy termination (M+P-) and mifepristone + progesterone (M+P+). Drug/vehicle administration occurred on day 12 of gestation (first-trimester human equivalent). Rat weight was measured throughout gestation. Uterine blood, collected post-drug/vehicle administration, was analyzed spectrophotometrically to measure blood loss. Additionally, at the end of gestation (day 21), ultrasound was utilized to confirm pregnancy and measure fetal heart rate. Number of gestational sacs, uterine weights and diameters were obtained following tissue collection. Our results indicate that progesterone administration following initiation of mifepristone-induced pregnancy termination (indicated by weight loss and uterine bleeding) reversed the process in 81% of rats in the M+P+ group. Following the initial weight loss, these rats proceeded to gain weight at a similar rate to the M-P- group, in contrast to the continued decrease displayed by the M+P- group (and unsuccessful reversals). Moreover, while uterine blood loss was similar to that of the M+P- group (confirming pregnancy termination initiation), number of gestational sacs, uterine weights, diameters, approximate fetal weights and fetal heart rates were similar to the M-P- group. Thus, our results indicate a clear progesterone-mediated reversal of an initiated mifepristone-induced pregnancy termination in a rat model at first-trimester human equivalent, with resultant fully developed living fetuses at the end of gestation, clearly indicating the necessity for further pre-clinical investigation to assist in better informing the scientific/medical communities of the potential implications in humans.

Society for Maternal-Fetal Medicine Statement: Response to the Food and Drug Administration's withdrawal of 17-alpha hydroxyprogesterone caproate

On April 5, 2023, the US Food and Drug Administration withdrew the approval of 17-alpha hydroxyprogesterone caproate, effective immediately, because of the lack of evidence that it reduces the risk of recurrent spontaneous preterm birth. This decision withdraws approval for all formulations of 17-alpha hydroxyprogesterone caproate (both intramuscular and subcutaneous) and applies to both brand name (Makena) and generic versions of the medication. We agree with the Food and Drug Administration determination and discourage continued prescribing of 17-alpha hydroxyprogesterone caproate, including through compounding pharmacies. We do not recommend changing indications for cerclage, indications for vaginal progesterone in patients with a short cervix, or recommendations against activity restriction based on the Food and Drug Administration withdrawal of 17-alpha hydroxyprogesterone caproate from the market. We recommend that discussion of the use of vaginal progesterone for primary prevention of recurrent preterm birth without input of cervical length or in those with a cervical length of ≥25 mm includes a shared decision-making process, especially if a progesterone formulation for preterm birth prevention was received in a previous pregnancy. The Food and Drug Administration determined that it would be inappropriate to delay the effective date of the withdrawal to allow patients currently receiving 17-alpha hydroxyprogesterone caproate to finish treatment. We agree with the Food and Drug Administration that there is no evidence of benefit with continued treatment. Patients currently receiving 17-alpha hydroxyprogesterone caproate can be counseled that the Food and Drug Administration's Center for Drug Evaluation and Research has not identified evidence of harm from discontinuation before 37 weeks of gestation.

Relationship between plasma concentration of 17-hydroxyprogesterone caproate and gestational age at preterm delivery

BACKGROUND

The effectiveness of 17-hydroxyprogesterone caproate is unclear as trials have provided conflicting results. With the absence of fundamental pharmacologic studies addressing dosing or the relationship between drug concentration and gestational age at delivery, the effectiveness of the medication cannot be evaluated.

OBJECTIVE

This study aimed to evaluate the relationship between plasma concentrations of 17-hydroxyprogesterone caproate and preterm birth rates and gestational age at preterm delivery and to assess the safety of the 500-mg dose.

STUDY DESIGN

This study recruited 2 cohorts with previous spontaneous preterm birth; 1 cohort (n=143) was randomly assigned to either 250-mg or 500-mg 17-hydroxyprogesterone caproate, and the other cohort (n=16) was receiving the 250-mg dose for routine care. Steady-state trough plasma concentrations of 17-hydroxyprogesterone caproate obtained at 26 to 30 weeks of gestation were correlated to dose, spontaneous preterm birth rates, and measures of gestational length. Furthermore, maternal and neonatal safety outcomes were evaluated according to dose.

RESULTS

There was a dose proportional increase in trough plasma concentrations with the 250-mg (median, 8.6 ng/m; n=66) and 500-mg (median, 16.2 ng/mL; n=55) doses. In 116 compliant participants with blood samples, drug concentration was not related to the spontaneous preterm birth rate (odds ratio, 1.00; 95% confidence interval, 0.93-1.08). However, there was a significant relationship between drug concentration and both the interval from the first administration to delivery (interval A: coefficient, 1.11; 95% confidence interval, 0.00-2.23; P=.05) and the interval from the 26- to 30-week blood draw to delivery (interval B: coefficient, 1.56; 95% confidence interval, 0.25-2.87; P=.02). The spontaneous preterm birth rate or measures of gestational length were not related to dose. Postenrollment cerclage adversely affected all pharmacodynamic assessments because it was a powerful predictor of spontaneous preterm birth (odds ratio, 4.03; 95% confidence interval, 1.24-13.19; P=.021) and both measures of gestational length (interval A [coefficient, -14.9; 95% confidence interval, -26.3 to -3.4; P=.011] and interval B [coefficient, -15.9; 95% confidence interval, -25.8 to -5.9; P=.002]). Initial cervical length was significantly related to the risk of postenrollment cerclage (odds ratio, 0.80; 95% confidence interval, 0.70-0.92; P=.001). Maternal and neonatal safety outcomes were similar in both dosing groups.

CONCLUSION

In this pharmacodynamic study, trough plasma 17-hydroxyprogesterone caproate concentrations were significantly associated with gestational age at preterm birth but not with the preterm birth rate. Postenrollment cerclage was a powerful predictor of spontaneous preterm birth rate and gestational length. Initial cervical length predicted the risk of postenrollment cerclage. Adverse events were similar with the 500-mg and 250-mg doses of 17-hydroxyprogesterone caproate.

Declining incidence of cerebral palsy in South Korea

Presuming that the incidence of cerebral palsy (CP) in Korea is decreasing due to medical advances, we analyzed the trends and risk factors of CP in changing circumstances. We identified all women who delivered a singleton between 2007 and 2015 using the Korea National Health Insurance (KNHI). Information on pregnancy and birth was obtained by linking the KNHI claims database and data from the national health-screening program for infants and children. The 4-years incidence of CP decreased significantly from 4.77 to 2.52 per 1000 babies during the study period. The multivariate analysis revealed that the risk of developing CP was 29.5 times higher in preterm infants born before 28 weeks of gestational age, 24.5 times higher in infants born between 28 and 34 weeks, and 4.5 times higher in infants born between 34 and 36 weeks, compared to full-term appropriate for age (2.5 ~ 4 kg of body weight) infants. 5.6 times higher in those with birth weight < 2500 g, and 3.8 times higher in pregnancies with polyhydramnios. Additionally, respiratory distress syndrome increased the risk of developing CP by 2.04 times, while necrotizing enterocolitis was associated with a 2.80-fold increased risk of CP. In Korea, the incidence of CP in singleton decreased from 2007 to 2015. We need to continue to focus on developing medical technologies for the early detection of high-risk neonates and minimizing brain damage to reduce the incidence rate of CP effectively.

The exciting potential for ChatGPT in obstetrics and gynecology

Natural language processing-the branch of artificial intelligence concerned with the interaction between computers and human language-has advanced markedly in recent years with the introduction of sophisticated deep-learning models. Improved performance in natural language processing tasks, such as text and speech processing, have fueled impressive demonstrations of these models' capabilities. Perhaps no demonstration has been more impactful to date than the introduction of the publicly available online chatbot ChatGPT in November 2022 by OpenAI, which is based on a natural language processing model known as a Generative Pretrained Transformer. Through a series of questions posed by the authors about obstetrics and gynecology to ChatGPT as prompts, we evaluated the model's ability to handle clinical-related queries. Its answers demonstrated that in its current form, ChatGPT can be valuable for users who want preliminary information about virtually any topic in the field. Because its educational role is still being defined, we must recognize its limitations. Although answers were generally eloquent, informed, and lacked a significant degree of mistakes or misinformation, we also observed evidence of its weaknesses. A significant drawback is that the data on which the model has been trained are apparently not readily updated. The specific model that was assessed here, seems to not reliably (if at all) source data from after 2021. Users of ChatGPT who expect data to be more up to date need to be aware of this drawback. An inability to cite sources or to truly understand what the user is asking suggests that it has the capability to mislead. Responsible use of models like ChatGPT will be important for ensuring that they work to help but not harm users seeking information on obstetrics and gynecology.

Prevention and Therapy of Preterm Birth. Guideline of the DGGG, OEGGG and SGGG (S2k-Level, AWMF Registry Number 015/025, September 2022) - Part 1 with Recommendations on the Epidemiology, Etiology, Prediction, Primary and Secondary Prevention of Preterm Birth

Aim This revised guideline was coordinated by the German Society for Gynecology and Obstetrics (DGGG), the Austrian Society for Gynecology and Obstetrics (OEGGG) and the Swiss Society for Gynecology and Obstetrics (SGGG). It aims to improve the prediction, prevention, and management of preterm birth, based on evidence from the current literature, the experience of members of the guidelines commission, and the viewpoint of self-help organizations. Methods The members of the contributing professional societies and organizations developed recommendations and statements based on international literature. The recommendations and statements were presented and adopted using a formal process (structured consensus conferences with neutral moderation, written Delphi vote). Recommendations Part 1 of this short version of the guideline presents statements and recommendations on the epidemiology, etiology, prediction, and primary and secondary prevention of preterm birth.

Understanding clinical outcome measures reported in HIV pregnancy studies involving antiretroviral-naive and antiretroviral-experienced women

HIV infection is a clinically significant public health disease and contributes to increased risk of maternal and fetal morbidity and mortality. HIV pregnancy studies use outcome measures as metrics to show how people with HIV feel, function, or survive. These endpoints are crucial for tracking the evolution of HIV illness over time, assessing the effectiveness of antiretroviral therapy (ART), and comparing outcomes across studies. Although the need for ideal outcome measures is widely acknowledged, selecting acceptable outcome measures for these HIV pregnancy studies can be challenging. We discuss the many outcome measures that have been implemented over time to assess HIV in pregnancy studies, their benefits, and drawbacks. Finally, we offer suggestions for improving the reporting of outcome measures in HIV in pregnancy studies. Medical professionals can best care for pregnant women living with HIV receiving ART by having a thorough understanding of these outcome metrics.

Nanomedicine strategies to improve therapeutic agents for the prevention and treatment of preterm birth and future directions

The World Health Organisation (WHO) estimates 15 million babies worldwide are born preterm each year, with 1 million infant mortalities and long-term morbidity in survivors. Whilst the past 40 years have provided some understanding in the causes of preterm birth, along with development of a range of therapeutic options, notably prophylactic use of progesterone or uterine contraction suppressants (tocolytics), the number of preterm births continues to rise. Existing therapeutics used to control uterine contractions are restricted in their clinical use due to pharmacological drawbacks such as poor potency, transfer of drugs to the fetus across the placenta and maternal side effects from activity in other maternal systems. This review focuses on addressing the urgent need for the development of alternative therapeutic systems with improved efficacy and safety for the treatment of preterm birth. We discuss the application of nanomedicine as a viable opportunity to engineer pre-existing tocolytic agents and progestogens into nanoformulations, to improve their efficacy and address current drawbacks to their use. We review different nanomedicines including liposomes, lipid-based carriers, polymers and nanosuspensions highlighting where possible, where these technologies have already been exploited e.g. liposomes, and their significance in improving the properties of pre-existing therapeutic agents within the field of obstetrics. We also highlight where active pharmaceutical agents (APIs) with tocolytic properties have been used for other clinical indications and how these could inform the design of future therapeutics or be repurposed to diversify their application such as for use in preterm birth. Finally we outline and discuss the future challenges.

Obstetric Indications for Progestin Therapy

Specifically, meta-analyses of randomized trials demonstrate that vaginal progesterone reduces the risk of preterm birth in selected high-risk singleton pregnancies. 17-OHPC may also reduce the risk of recurrent preterm birth in singletons. Finally, one trial suggests that vaginal progesterone may also be beneficial in improving live birth rates in singletons with prior miscarriages and early pregnancy bleeding.