In the name of God

The effect of intramuscular

progesterone on the rateof cervical shortening

Cara Pessel, MD et alAmerican Journal of Obstetrics and Gynecology

2013

The purpose of the study was: evaluate whether17-alpha-hydroxyprogesterone caproate (17-OHPC) exposure isassociated with the rate of cervical shortening.

Cervical length measurement inpregnancy has proved to be a usefultool in the identification of women whoAre at risk of spontaneous preterm delivery.

Serial assessments of the cervixand weekly intramuscular injections of17-alpha-hydroxyprogesterone caproate(17-OHPC)

Introduction

cervical length decreases withadvancing gestational age and that the cervix begins to shorten physiologically after 28 weeks’ gestation, even in womenwho are destined to deliver at term

mechanism by which 17-OHPC reduces the risk of recurrent preterm delivery is not well established.

A previous study reported no difference in the rate of cervical shortening among women with a history of spontaneous preterm delivery according to 17-OHPC exposure.

aberrations in cervical remodeling may predispose women to recurrent preterm deliveries and progesterone may function by targeting these aberrations, we hypothesized that women who experience recurrent preterm delivery and were exposed to progesterone may exhibit a slower rate of cervical shortening when compared with women who were not exposed to 17-OHPC.

a retrospective study among women with history of spontaneous preterm delivery (defined as 1 spontaneous births between 16

weeks and 36 weeks 6 days’ gestation)who underwent serial cervical lengthassessments to monitor for cervicalshortening in our institution between2009 and 2012

MATERIALS AND METHODS

Pregnancies with1. major fetal anomalies,2.vaginal progesterone use at any timein the index pregnancy,3. <2 cervical length measurements4. medically indicated preterm delivery, or5. the presence or placement of an

abdominal or vaginal cerclage were excluded.

Electronic medical records were reviewed to abstract pertinent obstetric history, including the number of previous preterm deliveries, gestational age of each preterm delivery, and whether that pregnancy involved multiple gestations.

maternal age, race,ethnicity, prepregnancy and weight at

delivery, type of provider (private maternal-fetal medicine specialist, private generalist obstetrician and gynecologist

(OB/GYN), or government-insured OB/GYN low-risk clinic or high-risk maternal-fetal medicine clinic), use of in vitro fertilization, smoking status, and illicit drug use during pregnancy.

• At our center, women with a history ospontaneous delivery at <37 weeks’ gestation are offered weekly treatment with 17-OHPC starting at 16 gestational weeks.

• Review of our electronic ultrasound database was used to record cervical length measurements (in millimeters) from 16-32 weeks’ gestation

The obstetrics ultrasoundguidelines at Columbia UniversityMedical Center require 3 measurementsof the cervix that include at least 1assessment while the patient performsthe Valsalva maneuver. The shortest ofthe 3 cervical length values is reportedclinically; this measurement was recordedinto our database for each visit

Short cervix is defined at our institutionas <25 mm, which represents the10th percentile at 24 weeks’ gestation.Once this is identified in our ultrasoundunit, patient treatment variesaccording to practitioner and individualpatient details and may involve cerclageplacement, the initiation of vaginalprogesterone, or expectant treatmentand observation

the goal of our protocol was to identifyall women who may benefit from

timesensitiveinterventions such as antenatalsteroid and magnesium administration

Of 17,400 deliveries from 2009-2012, 376 women with a history of spontaneous preterm delivery met inclusion criteria.

We excluded 139 women: major fetal anomalies, 5 women; the presenceof placement of a cerclage (2 abdominaland 78 vaginal), 80 women; exposure tovaginal progesterone, 32 women; indicatedpreterm delivery, 22 women.

This resulted in 237 women for analysis. Of the included patients, 184 (77.6%) were exposed to 17-OHPC in the current pregnancy.

Results

Women who were exposed to 17-OHPC were, on average, 2.2 years younger None of the other characteristics, including previous uterine or cervical surgery, differed between the groups.

Subjects who were not exposed to 17-OHPC were more likely to have a previous preterm delivery that involved a multiple gestation

obstetric history of recurrent preterm delivery, gestational age at earliest preterm delivery, and history of at least 1 term delivery was similar between those who were exposed to 17-OHPC and those not.

The first cervical length measurements (41.6 vs 40.7 mm; P ¼.52) were similar, regardles of 17-OHPC exposure. The number of cervical length measurements was higher in women who wereexposed to 17-OHPC (median of 5 exams vs 3 in those who were not exposed to 17-OHPC; P <.01).

The average rates of cervical shortening per week among term deliveries were 0.9 and 0.8 mm

with and without 17-OHPC, respectively(P ¼ .76). Among preterm deliveries,the corresponding rates were 0.8 and1.2 mm, respectively, among womenwith and without 17-OHPC (P ¼.67).

Rates of spontaneous preterm delivery in thecurrent pregnancy on exposure to 17-OHPC

did not differ based.

Thank You for you attention