Relationship between timing of ovariectomy and maintenance of pregnancy in the guinea-pig

Csapo, A.I.; Puri, Claudia; Tarró, S

doi:10.1016/0090-6980(81)90060-5

Cited by 23 publications

(10 citation statements)

References 8 publications

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“…The precise mechanism by which progesterone prevents preterm delivery in women with a short cervix has not been established. A local effect is likely, given the high concentrations of circulating progesterone in pregnant women97, 98.…”

Section: Discussionmentioning

confidence: 99%

Vaginal progesterone reduces the rate of preterm birth in women with a sonographic short cervix: a multicenter, randomized, double‐blind, placebo‐controlled trial

Hassan¹,

Romero²,

Vidyadhari³

et al. 2011

Ultrasound in Obstet & Gyne

828

585

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Objectives Women with a sonographic short cervix in the mid-trimester are at increased risk for preterm delivery. This study was undertaken to determine the ef cacy and safety of using micronized vaginal progesterone gel to reduce the risk of preterm birth and associated neonatal complications in women with a sonographic short cervix. Methods This was a multicenter, randomized, double-blind, placebo-controlled trial that enrolled asymptomatic women with a singleton pregnancy and a sonographic short cervix (10–20 mm) at 19 + 0to23 + 6 weeks of gestation. Women were allocated randomly to receive vaginal progesterone gel or placebo daily starting from 20 to 23 + 6 weeks until 36 + 6 weeks, rupture of membranes or delivery, whichever occurred rst. Randomization sequence was strati ed by center and history of a previous preterm birth. The primary endpoint was preterm birth before 33 weeks of gestation. Analysis was by intention to treat. Results Of 465 women randomized, seven were lost to follow-up and 458 (vaginal progesterone gel, n = 235; placebo, n = 223) were included in the analysis. Women allocated to receive vaginal progesterone had a lower rate of preterm birth before 33 weeks than did those allocated to placebo (8.9% (n = 21) vs 16.1% (n = 36); relative risk (RR), 0.55; 95% CI, 0.33–0.92; P = 0.02). The effect remained signi cant after adjustment for covariables (adjusted RR, 0.52; 95% CI, 0.31–0.91; P = 0.02). Vaginal progesterone was also associated with a signi cant reduction in the rate of preterm birth before 28 weeks(5.1%vs10.3%; RR, 0.50;95%CI, 0.25–0.97; P = 0.04) and 35 weeks (14.5% vs 23.3%; RR, 0.62; 95% CI, 0.42–0.92; P = 0.02), respiratory distress syndrome (3.0% vs 7.6%; RR, 0.39; 95% CI, 0.17–0.92; P = 0.03), any neonatal morbidity or mortality event (7.7% vs 13.5%; RR, 0.57; 95% CI, 0.33–0.99; P = 0.04) and birth weight < 1500 g (6.4% (15/234) vs 13.6% (30/220); RR, 0.47; 95% CI, 0.26–0.85; P = 0.01). There were no differences in the incidence of treatment-related adverse events between the groups. Conclusions The administration of vaginal progesterone gel to women with a sonographic short cervix in the mid-trimester is associated with a 45% reduction in the rate of preterm birth before 33 weeks of gestation and with improved neonatal outcome.

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Section: Discussionmentioning

confidence: 99%

Vaginal progesterone reduces the rate of preterm birth in women with a sonographic short cervix: a multicenter, randomized, double‐blind, placebo‐controlled trial

Hassan¹,

Romero²,

Vidyadhari³

et al. 2011

Ultrasound in Obstet & Gyne

828

585

View full text Add to dashboard Cite

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“…Pregnancy maintenance in guinea pigs does not require a functioning corpus luteum during the second half of gestation, because a luteo‐placental shift of progesterone production occurs around the 4th week of pregnancy (Csapo et al 1981). This is analogous to the luteo‐placental shift of progesterone production in early human pregnancy and suggests that the endocrine mechanisms that maintain and terminate pregnancy are similar in the two species.…”

Section: Discussionmentioning

confidence: 99%

Prostaglandin H₂ synthase‐1 and ‐2 expression in guinea pig gestational tissues during late pregnancy and parturition

Welsh¹,

Mitchell²,

Walters³

et al. 2005

The Journal of Physiology

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Increased intrauterine prostaglandin (PG) production is crucial for the initiation of parturition.To investigate the mechanisms controlling intrauterine PG synthesis, we examined the expression of the key PG biosynthetic isoenzymes, PG-H 2 synthase (PTGS)-1 and -2, in the amnion, visceral yolk sac (VYS), placenta and myo-endometrium of pregnant guinea pigs. This animal model was chosen because the hormonal milieu of pregnancy and the role of PGs in the hormonal control of parturition are similar to those in the human. PTGS1 mRNA abundance, measured by real-time RT-PCR, increased in the amnion and the placenta during the last third of gestation. During labour, PTGS1 mRNA levels decreased precipitously in all four tissues. PTGS1 protein abundance, assessed by immunoblotting, increased to high levels in the amnion and the placenta by the end of pregnancy and remained high during labour. PTGS2 mRNA expression was higher in the placenta than in the other tissues, but did not change before and during labour. PTGS2 protein expression decreased in the placenta and remained low in the other tissues during labour. Immunohistochemistry showed pervasive PTGS1 protein expression in the amnion and strong expression in the parietal yolk sac membrane (PYS) covering the placenta. PTGS2 was expressed in the PYS and the endometrium. The PTGS inhibitor piroxicam, administered in doses that inhibited PTGS1 but not PTGS2, significantly prolonged gestation. These data suggest that PGs generated by intrauterine PTGS1 are involved in the timing of birth in guinea pigs. The induction of PTGS1 in the amnion and the PYS is a critical event leading to labour in guinea pigs and models analogous changes in the human gestational tissues before labour.

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“…Placental progesterone production in guinea pigs means that, similar to the human, maintenance of pregnancy is independent of the ovary in the second half of pregnancy (Csapo et al . ). Conversely, ovariectomy induces parturition and/or pregnancy loss in mice and rats throughout pregnancy (Fig.…”

Section: Introductionmentioning

confidence: 97%

Guinea pig models for translation of the developmental origins of health and disease hypothesis into the clinic

Morrison

Botting

Darby

et al. 2018

The Journal of Physiology

123

108

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Over 30 years ago Professor David Barker first proposed the theory that events in early life could explain an individual's risk of non-communicable disease in later life: the developmental origins of health and disease (DOHaD) hypothesis. During the 1990s the validity of the DOHaD hypothesis was extensively tested in a number of human populations and the mechanisms underpinning it characterised in a range of experimental animal models. Over the past decade, researchers have sought to use this mechanistic understanding of DOHaD to develop therapeutic interventions during pregnancy and early life to improve adult health. A variety of animal models have been used to develop and evaluate interventions, each with strengths and limitations. It is becoming apparent that effective translational research requires that the animal paradigm selected mirrors the tempo of human fetal growth and development as closely as possible so that the effect of a perinatal insult and/or therapeutic intervention can be fully assessed. The guinea pig is one such animal model that over the past two decades has demonstrated itself to be a very useful platform for these important reproductive studies. This review highlights similarities in the in utero development between humans and guinea pigs, the strengths and limitations of the guinea pig as an experimental model of DOHaD and the guinea pig's potential to enhance clinical therapeutic innovation to improve human health.

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Relationship between timing of ovariectomy and maintenance of pregnancy in the guinea-pig

Cited by 23 publications

References 8 publications

Vaginal progesterone reduces the rate of preterm birth in women with a sonographic short cervix: a multicenter, randomized, double‐blind, placebo‐controlled trial

Vaginal progesterone reduces the rate of preterm birth in women with a sonographic short cervix: a multicenter, randomized, double‐blind, placebo‐controlled trial

Prostaglandin H₂ synthase‐1 and ‐2 expression in guinea pig gestational tissues during late pregnancy and parturition

Guinea pig models for translation of the developmental origins of health and disease hypothesis into the clinic

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Relationship between timing of ovariectomy and maintenance of pregnancy in the guinea-pig

Cited by 23 publications

References 8 publications

Vaginal progesterone reduces the rate of preterm birth in women with a sonographic short cervix: a multicenter, randomized, double‐blind, placebo‐controlled trial

Vaginal progesterone reduces the rate of preterm birth in women with a sonographic short cervix: a multicenter, randomized, double‐blind, placebo‐controlled trial

Prostaglandin H2 synthase‐1 and ‐2 expression in guinea pig gestational tissues during late pregnancy and parturition

Guinea pig models for translation of the developmental origins of health and disease hypothesis into the clinic

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Prostaglandin H₂ synthase‐1 and ‐2 expression in guinea pig gestational tissues during late pregnancy and parturition