Intrauterine growth restriction

Last updated
Intrauterine growth restriction
Other namesFetal growth restriction (FGR), [1] [2] intrauterine growth retardation, [3] [4]
Villitis of unknown etiology - very high mag.jpg
Micrograph of villitis of unknown etiology, a placental pathology associated with IUGR. H&E stain.
Specialty Pediatrics, obstetrics   OOjs UI icon edit-ltr-progressive.svg

Intrauterine growth restriction (IUGR), or fetal growth restriction, is the poor growth of a fetus while in the womb during pregnancy. IUGR is defined by clinical features of malnutrition and evidence of reduced growth regardless of an infant's birth weight percentile. [5] The causes of IUGR are broad and may involve maternal, fetal, or placental complications. [6]

Contents

At least 60% of the 4 million neonatal deaths that occur worldwide every year are associated with low birth weight (LBW), caused by intrauterine growth restriction (IUGR), preterm delivery, and genetic abnormalities, [7] demonstrating that under-nutrition is already a leading health problem at birth.

Intrauterine growth restriction can result in a baby being small for gestational age (SGA), which is most commonly defined as a weight below the 10th percentile for the gestational age. [8] At the end of pregnancy, it can result in a low birth weight.

Types

There are two major categories of IUGR: pseudo IUGR and true IUGR[ citation needed ]

With pseudo IUGR, the fetus has a birth weight below the tenth percentile for the corresponding gestational age but has a normal ponderal index, subcutaneous fat deposition, and body proportion. Pseudo IUGR occurs due to uneventful intrauterine course and can be rectified by proper postnatal care and nutrition. Such babies are also called small for gestational age.[ citation needed ]

True IUGR occurs due to pathological conditions which may be either fetal or maternal in origin. In addition to low body weight they have abnormal ponderal index, body disproportion, and low subcutaneous fat deposition. There are two types-symmetrical and asymmetrical. [9] [10] Some conditions are associated with both symmetrical and asymmetrical growth restriction.[ citation needed ]

Asymmetrical

Asymmetrical IUGR accounts for 70-80% of all IUGR cases. [11] In asymmetrical IUGR, there is decreased oxygen or nutrient supply to the fetus during the third trimester of pregnancy due to placental insufficiency. [12] This type of IUGR is sometimes called "head sparing" because brain growth is typically less affected, resulting in a relatively normal head circumference in these children. [13] Because of decreased oxygen supply to the fetus, blood is diverted to the vital organs, such as the brain and heart. As a result, blood flow to other organs - including liver, muscle, and fat - is decreased. This causes abdominal circumference in these children to be decreased. [13]

A lack of subcutaneous fat leads to a thin and small body out of proportion with the liver. Normally at birth the brain of the fetus is 3 times the weight of its liver. In IUGR, it becomes 5-6 times. In these cases, the embryo/fetus has grown normally for the first two trimesters but encounters difficulties in the third, sometimes secondary to complications such as pre-eclampsia. Other symptoms than the disproportion include dry, peeling skin and an overly-thin umbilical cord. The baby is at increased risk of hypoxia and hypoglycemia. This type of IUGR is most commonly caused by extrinsic factors that affect the fetus at later gestational ages. Specific causes include:[ citation needed ]

Symmetrical

Symmetrical IUGR is commonly known as global growth restriction, and indicates that the fetus has developed slowly throughout the duration of the pregnancy and was thus affected from a very early stage. The head circumference of such a newborn is in proportion to the rest of the body. Since most neurons are developed by the 18th week of gestation, the fetus with symmetrical IUGR is more likely to have permanent neurological sequelae. Common causes include:[ citation needed ]

Causes

IUGR is caused by a variety of factors; these can be fetal, maternal, placental or genetic factors. [11]

Maternal

Uteroplacental

Fetal

Genetic

Pathophysiology

If the cause of IUGR is extrinsic to the fetus (parental or uteroplacental), transfer of oxygen and nutrients to the fetus is decreased. This causes a reduction in the fetus' stores of glycogen and lipids. This often leads to hypoglycemia at birth. Polycythemia can occur secondary to increased erythropoietin production caused by the chronic hypoxemia. Hypothermia, thrombocytopenia, leukopenia, hypocalcemia, and bleeding in the lungs are often results of IUGR. [5]

Infants with IUGR are at increased risk of perinatal asphyxia due to chronic hypoxia, usually associated with placental insufficiency, placental abruption, or a umbilical cord accident. [16] This chronic hypoxia also places IUGR infants at elevated risk of persistent pulmonary hypertension of the newborn, which can impair an infant's blood oxygenation and transition to postnatal circulation. [17]

If the cause of IUGR is intrinsic to the fetus, growth is restricted due to genetic factors or as a sequela of infection. IUGR is associated with a wide range of short- and long-term neurodevelopmental disorders.[ citation needed ]

Cardiovascular

In IUGR, there is an increase in vascular resistance in the placental circulation, causing an increase in cardiac afterload. There is also increased vasoconstriction of the arteries in the periphery, which occurs in response to chronic hypoxia in order to preserve adequate blood flow to the fetus' vital organs. [18] This prolonged vasoconstriction leads to remodeling and stiffening of the arteries, which also contributes to the increase in cardiac afterload. Therefore, the fetal heart must work harder to contract during each heartbeat, which leads to an increase in wall stress and cardiac hypertrophy. [19] These changes in the fetal heart lead to increased long-term risk of hypertension, atherosclerosis, cardiovascular disease, and stroke. [19]

Pulmonary

Normal lung development is interrupted in fetuses with IUGR, which increases their risk for respiratory compromise and impaired lung function later in life. Preterm infants with IUGR are more likely to have bronchopulmonary dysplasia (BPD), a chronic lung disease that is thought to be associated with prolonged use of mechanical ventilation. [19]

Neurological

IUGR is associated with long-term motor deficits and cognitive impairment. [19] In order to adapt to the chronic hypoxia associated with placental insufficiency, blood flow is redirected to the brain to try to preserve brain growth and development as much as possible. Even though this is thought to be protective, fetuses with IUGR who have undergone this brain-sparing adaptation have worse neurological outcomes compared with those who have not undergone this adaptation. [20]

Magnetic resonance imaging (MRI) can detect changes in volume and structural development of infants with IUGR compared with those whose growth is appropriate for gestational age (AGA). But MRI is not easily accessible for all patients. [19]

White matter effects – In postpartum studies of infants, it was shown that there was a decrease of the fractal dimension of the white matter in IUGR infants at one year corrected age. This was compared to at term and preterm infants at one year adjusted corrected age.[ citation needed ]

Grey matter effects – Grey matter was also shown to be decreased in infants with IUGR at one year corrected age. [21]

Children with IUGR are often found to exhibit brain reorganization including neural circuitry. [22] Reorganization has been linked to learning and memory differences between children born at term and those born with IUGR. [23]

Studies have shown that children born with IUGR had lower IQ. They also exhibit other deficits that point to frontal lobe dysfunction.[ citation needed ]

IUGR infants with brain-sparing show accelerated maturation of the hippocampus which is responsible for memory. [24] This accelerated maturation can often lead to uncharacteristic development that may compromise other networks and lead to memory and learning deficiencies.[ citation needed ]

Management

Mothers whose fetus is diagnosed with intrauterine growth restriction can be managed with several monitoring and delivery methods. It is currently recommended that any fetus that has growth restriction and additional structural abnormalities should be evaluated with genetic testing. [6] In addition to evaluating the fetal growth velocity, the fetus should primarily be monitored by ultrasonography every 3–4 weeks. [6] An additional monitoring technique is an Doppler velocimetry. Doppler velocimetry is useful in monitoring blood flow through the uterine and umbilical arteries, and may indicate signs of uteroplacental insufficiency. [25] This method may also detect blood vessels, specifically the ductus venosus and middle cerebral arteries, which are not developing properly or may not adapt well after birth. [25] Monitoring via Doppler velocimetry has been shown to decrease the risk of morbidity and mortality before and after parturition among IUGR patients. [26] Standard fetal surveillance via nonstress tests and/or biophysical profile scoring is also recommended. [25] [6] Bed rest has not been found to improve outcomes and is not typically recommended. [27] There is currently a lack of evidence supporting any dietary or supplemental changes that may prevent the development of IUGR. [6]

The optimal timing of delivery for a fetus with IUGR is unknown. However, the timing of delivery is currently based on the cause of IUGR [6] and parameters collected from the umbilical artery doppler. Some of these include: pulsatility index, resistance index, and end-diastolic velocities, which are measurements of the fetal circulation. [26] Fetuses with an anticipated delivery before 34 weeks gestation are recommended to receive corticosteroids to facilitate fetal maturation. [6] [28] Anticipated births before 32 weeks should receive magnesium sulfate to protect development of the fetal brain. [29]

Outcomes

Postnatal complications

After correcting for several factors such as low gestational parental weight, it is estimated that only around 3% of pregnancies are affected by true IUGR. 20% of stillborn infants exhibit IUGR. Perinatal mortality rates are 4-8 times higher for infants with IUGR, and morbidity is present in 50% of surviving infants. [30] Common causes of mortality in fetuses/infants with IUGR include: severe placental insufficiency and chronic hypoxia, congenital malformations, congenital infections, placental abruption, cord accidents, cord prolapse, placental infarcts, and severe perinatal depression. [5]

IUGR is more common in preterm infants than in full term (37–40 weeks gestation) infants, and its frequency decreases with increasing gestational age. Relative to premature infants who do not exhibit IUGR, premature infants with IUGR are more likely to have adverse neonatal outcomes, including respiratory distress syndrome, intraventricular hemorrhage, and necrotizing enterocolitis. This association with prematurity suggests utility of screening for IUGR as a potential risk factor for preterm labor. [31]

Feeding intolerance, hypothermia, hypoglycemia, and hyperglycemia are all common in infants in the postnatal period, indicating the need to closely manage these patients' temperature and nutrition. [32] Furthermore, rapid metabolic and physiologic changes in the first few days after birth can yield susceptibility to hypocalcemia, polycythemia, immunologic compromise, and renal dysfunction. [33] [34]

Long-term consequences

According to the theory of thrifty phenotype, intrauterine growth restriction triggers epigenetic responses in the fetus that are otherwise activated in times of chronic food shortage. If the offspring actually develops in an environment where food is readily accessible, it may be more prone to metabolic disorders, such as obesity and type II diabetes. [35]

Infants with IUGR may continue to show signs of abnormal growth throughout childhood. Infants with asymmetric IUGR (head-sparing) typically have more robust catch-up postnatal growth, as compared with infants with symmetric IUGR, who may remain small throughout life. The majority of catch-up growth occurs in the first 6 months of life, but can continue throughout the first two years. Approximately 10% of infants who are small for gestational age due to IUGR will still have short stature in late childhood. [36]

Infants with IUGR are also at elevated risk for neurodevelopmental abnormalities, including motor delay and cognitive impairments. Low IQ in adulthood may occur in up to one third of infants born small for gestational age due to IUGR. Infants who fail to display adequate catch-up growth in the first few years of life may exhibit worse outcomes. [37] [38]

Catch-up growth can alter fat distribution in children diagnosed with IUGR as infants and increase risk of metabolic syndrome. [39] Infants with IUGR may be susceptible to long-term dysfunction of several endocrine processes, including growth hormone signaling, the hypothalamic-pituitary-adrenal axis, and puberty. [40] Renal dysfunction, disrupted lung development, and impaired bone metabolism are also associated with IUGR. [41]

Animals

In sheep, intrauterine growth restriction can be caused by heat stress in early to mid pregnancy. The effect is attributed to reduced placental development causing reduced fetal growth. [42] [43] [44] Hormonal effects appear implicated in the reduced placental development. [44] Although early reduction of placental development is not accompanied by concurrent reduction of fetal growth; [42] it tends to limit fetal growth later in gestation. Normally, ovine placental mass increases until about day 70 of gestation, [45] but high demand on the placenta for fetal growth occurs later. (For example, research results suggest that a normal average singleton Suffolk x Targhee sheep fetus has a mass of about 0.15 kg at day 70, and growth rates of about 31 g/day at day 80, 129 g/day at day 120 and 199 g/day at day 140 of gestation, reaching a mass of about 6.21 kg at day 140, a few days before parturition. [46] )

In adolescent ewes (i.e. ewe hoggets), overfeeding during pregnancy can also cause intrauterine growth restriction, by altering nutrient partitioning between dam and conceptus. [47] [48] Fetal growth restriction in adolescent ewes overnourished during early to mid pregnancy is not avoided by switching to lower nutrient intake after day 90 of gestation; whereas such switching at day 50 does result in greater placental growth and enhanced pregnancy outcome. [48] Practical implications include the importance of estimating a threshold for "overnutrition" in management of pregnant ewe hoggets. In a study of Romney and Coopworth ewe hoggets bred to Perendale rams, feeding to approximate a conceptus-free live mass gain of 0.15 kg/day (i.e. in addition to conceptus mass), commencing 13 days after the midpoint of a synchronized breeding period, yielded no reduction in lamb birth mass, where compared with feeding treatments yielding conceptus-free live mass gains of about 0 and 0.075 kg/day. [49] In both of the above models of IUGR in sheep, the absolute magnitude of uterine blood flow is reduced. [48] Evidence of substantial reduction of placental glucose transport capacity has been observed in pregnant ewes that had been heat-stressed during placental development. [50] [51]

See also

Related Research Articles

Fetal distress, also known as non-reassuring fetal status, is a condition during pregnancy or labor in which the fetus shows signs of inadequate oxygenation. Due to its imprecision, the term "fetal distress" has fallen out of use in American obstetrics. The term "non-reassuring fetal status" has largely replaced it. It is characterized by changes in fetal movement, growth, heart rate, and presence of meconium stained fluid.

Oligohydramnios is a medical condition in pregnancy characterized by a deficiency of amniotic fluid, the fluid that surrounds the fetus in the abdomen, in the amniotic sac. The limiting case is anhydramnios, where there is a complete absence of amniotic fluid. It is typically diagnosed by ultrasound when the amniotic fluid index (AFI) measures less than 5 cm or when the single deepest pocket (SDP) of amniotic fluid measures less than 2 cm. Amniotic fluid is necessary to allow for normal fetal movement, lung development, and cushioning from uterine compression. Low amniotic fluid can be attributed to a maternal, fetal, placental or idiopathic cause and can result in poor fetal outcomes including death. The prognosis of the fetus is dependent on the etiology, gestational age at diagnosis, and the severity of the oligohydramnios.

<span class="mw-page-title-main">Small for gestational age</span> Medical condition

Small for gestational age (SGA) newborns are those who are smaller in size than normal for the gestational age. SGA is most commonly defined as a weight below the 10th percentile for the gestational age. SGA predicts susceptibility to hypoglycemia, hypothermia, and polycythemia. By definition, at least 10% of all newborns will be labeled SGA. All SGA babies should be watched for signs of failure to thrive, hypoglycemia and other health conditions.

Tocolytics are medications used to suppress premature labor. Preterm birth accounts for 70% of neonatal deaths. Therefore, tocolytic therapy is provided when delivery would result in premature birth, postponing delivery long enough for the administration of glucocorticoids, which accelerate fetal lung maturity but may require one to two days to take effect.

In obstetrics, gestational age is a measure of the age of a pregnancy taken from the beginning of the woman's last menstrual period (LMP), or the corresponding age of the gestation as estimated by a more accurate method, if available. Such methods include adding 14 days to a known duration since fertilization, or by obstetric ultrasonography. The popularity of using this measure of pregnancy is largely due to convenience: menstruation is usually noticed, while there is generally no convenient way to discern when fertilization or implantation occurred.

Environmental toxicants and fetal development is the impact of different toxic substances from the environment on the development of the fetus. This article deals with potential adverse effects of environmental toxicants on the prenatal development of both the embryo or fetus, as well as pregnancy complications. The human embryo or fetus is relatively susceptible to impact from adverse conditions within the mother's environment. Substandard fetal conditions often cause various degrees of developmental delays, both physical and mental, for the growing baby. Although some variables do occur as a result of genetic conditions pertaining to the father, a great many are directly brought about from environmental toxins that the mother is exposed to.

<span class="mw-page-title-main">Low birth weight</span> Birth weight of an infant of 2,499 g (5 lb 8.1 oz) or less

Low birth weight (LBW) is defined by the World Health Organization as a birth weight of an infant of 2,499 g or less, regardless of gestational age. Infants born with LBW have added health risks which require close management, often in a neonatal intensive care unit (NICU). They are also at increased risk for long-term health conditions which require follow-up over time.

Prenatal development involves the development of the embryo and of the fetus during a viviparous animal's gestation. Prenatal development starts with fertilization, in the germinal stage of embryonic development, and continues in fetal development until birth.

<span class="mw-page-title-main">Prelabor rupture of membranes</span> Breakage of the amniotic sac before the onset of labour

Prelabor rupture of membranes (PROM), previously known as premature rupture of membranes, is breakage of the amniotic sac before the onset of labour. Women usually experience a painless gush or a steady leakage of fluid from the vagina. Complications in the baby may include premature birth, cord compression, and infection. Complications in the mother may include placental abruption and postpartum endometritis.

<span class="mw-page-title-main">Complications of pregnancy</span> Medical condition

Complications of pregnancy are health problems that are related to, or arise during pregnancy. Complications that occur primarily during childbirth are termed obstetric labor complications, and problems that occur primarily after childbirth are termed puerperal disorders. While some complications improve or are fully resolved after pregnancy, some may lead to lasting effects, morbidity, or in the most severe cases, maternal or fetal mortality.

Antenatal steroids, also known as antenatal corticosteroids, are medications administered to pregnant women expecting a preterm birth. When administered, these steroids accelerate the maturation of the fetus' lungs, which reduces the likelihood of infant respiratory distress syndrome and infant mortality. The effectiveness of this corticosteroid treatment on humans was first demonstrated in 1972 by Sir Graham Liggins and Ross Howie, during a randomized control trial using betamethasone.

<span class="mw-page-title-main">Intrauterine hypoxia</span> Medical condition when the fetus is deprived of sufficient oxygen

Intrauterine hypoxia occurs when the fetus is deprived of an adequate supply of oxygen. It may be due to a variety of reasons such as prolapse or occlusion of the umbilical cord, placental infarction, maternal diabetes and maternal smoking. Intrauterine growth restriction may cause or be the result of hypoxia. Intrauterine hypoxia can cause cellular damage that occurs within the central nervous system. This results in an increased mortality rate, including an increased risk of sudden infant death syndrome (SIDS). Oxygen deprivation in the fetus and neonate have been implicated as either a primary or as a contributing risk factor in numerous neurological and neuropsychiatric disorders such as epilepsy, attention deficit hyperactivity disorder, eating disorders and cerebral palsy.

Placental insufficiency or utero-placental insufficiency is the failure of the placenta to deliver sufficient nutrients to the fetus during pregnancy, and is often a result of insufficient blood flow to the placenta. The term is also sometimes used to designate late decelerations of fetal heart rate as measured by cardiotocography or an NST, even if there is no other evidence of reduced blood flow to the placenta, normal uterine blood flow rate being 600mL/min.

<span class="mw-page-title-main">Velamentous cord insertion</span> Velamentous placenta

Velamentous cord insertion is a complication of pregnancy where the umbilical cord is inserted in the fetal membranes. It is a major cause of antepartum hemorrhage that leads to loss of fetal blood and associated with high perinatal mortality. In normal pregnancies, the umbilical cord inserts into the middle of the placental mass and is completely encased by the amniotic sac. The vessels are hence normally protected by Wharton's jelly, which prevents rupture during pregnancy and labor. In velamentous cord insertion, the vessels of the umbilical cord are improperly inserted in the chorioamniotic membrane, and hence the vessels traverse between the amnion and the chorion towards the placenta. Without Wharton's jelly protecting the vessels, the exposed vessels are susceptible to compression and rupture.

A fetus or foetus is the unborn offspring that develops from a mammal embryo. Following embryonic development, the fetal stage of development takes place. In human prenatal development, fetal development begins from the ninth week after fertilization and continues until the birth of a newborn. Prenatal development is a continuum, with no clear defining feature distinguishing an embryo from a fetus. However, a fetus is characterized by the presence of all the major body organs, though they will not yet be fully developed and functional and some not yet situated in their final anatomical location.

<span class="mw-page-title-main">Placental disease</span> Medical condition

A placental disease is any disease, disorder, or pathology of the placenta.

<span class="mw-page-title-main">Circumvallate placenta</span> Medical condition

Circumvallate placenta is a rare condition affecting about 1-2% of pregnancies, in which the amnion and chorion fetal membranes essentially "double back" on the fetal side around the edges of the placenta. After delivery, a circumvallate placenta has a thick ring of membranes on its fetal surface. Circumvallate placenta is a placental morphological abnormality associated with increased fetal morbidity and mortality due to the restricted availability of nutrients and oxygen to the developing fetus.

<span class="mw-page-title-main">High-risk pregnancy</span> Medical condition

A high-risk pregnancy is a pregnancy where the mother or the fetus has an increased risk of adverse outcomes compared to uncomplicated pregnancies. No concrete guidelines currently exist for distinguishing “high-risk” pregnancies from “low-risk” pregnancies; however, there are certain studied conditions that have been shown to put the mother or fetus at a higher risk of poor outcomes. These conditions can be classified into three main categories: health problems in the mother that occur before she becomes pregnant, health problems in the mother that occur during pregnancy, and certain health conditions with the fetus.

A pre-existing disease in pregnancy is a disease that is not directly caused by the pregnancy, in contrast to various complications of pregnancy, but which may become worse or be a potential risk to the pregnancy. A major component of this risk can result from necessary use of drugs in pregnancy to manage the disease.

Fetal programming, also known as prenatal programming, is the theory that environmental cues experienced during fetal development play a seminal role in determining health trajectories across the lifespan.

References

  1. "UpToDate".
  2. "Intrauterine Growth Restriction. IUGR information".
  3. Vandenbosche, Robert C.; Kirchner, Jeffrey T. (15 October 1998). "Intrauterine Growth Retardation". American Family Physician . 56 (6): 1384–1390. PMID   9803202 . Retrieved 20 February 2016. Intrauterine growth retardation (IUGR), which is defined as less than 10 percent of predicted fetal weight for gestational age, may result in significant fetal morbidity and mortality if not properly diagnosed. The condition is most commonly caused by inadequate maternal-fetal circulation, with a resultant decrease in fetal growth.
  4. White, Cynthia D. (16 November 2014). "Intrauterine growth restriction". MedlinePlus Medical Encyclopedia. Retrieved 21 February 2016. Alternative Names: Intrauterine growth retardation; IUGR
  5. 1 2 3 Kesavan, K.; Devaskar, S. U. (2019-04-01). "Intrauterine Growth Restriction: Postnatal Monitoring and Outcomes". Pediatric Clinics of North America. 66 (2): 403–423. doi:10.1016/j.pcl.2018.12.009. ISSN   0031-3955. PMID   30819345. S2CID   73488004.
  6. 1 2 3 4 5 6 7 "Fetal Growth Restriction: ACOG Practice Bulletin, Number 227". Obstetrics & Gynecology. 137 (2): e16–e28. February 2021. doi:10.1097/AOG.0000000000004251. ISSN   0029-7844. PMID   33481528. S2CID   231680750.
  7. Lawn JE, Cousens S, Zupan J (2005). "4 million neonatal deaths: when? Where? Why?". The Lancet. 365 (9462): 891–900. doi:10.1016/s0140-6736(05)71048-5. PMID   15752534. S2CID   20891663.
  8. Small for gestational age (SGA) at MedlinePlus. Update Date: 8/4/2009. Updated by: Linda J. Vorvick. Also reviewed by David Zieve.
  9. "Intrauterine Growth Restriction". Archived from the original on 2007-06-09. Retrieved 2007-11-28.
  10. Hunter, Stephen K.; Kennedy, Colleen M.; Peleg, David (August 1998). "Intrauterine Growth Restriction: Identification and Management - August 1998 - American Academy of Family Physicians". American Family Physician. 58 (2): 453–60, 466–7. PMID   9713399. Archived from the original on 2011-06-06. Retrieved 2007-11-28.
  11. 1 2 Sharma, Deepak; Shastri, Sweta; Sharma, Pradeep (2016). "Intrauterine Growth Restriction: Antenatal and Postnatal Aspects". Clinical Medicine Insights. Pediatrics. 10: 67–83. doi:10.4137/CMPed.S40070. ISSN   1179-5565. PMC   4946587 . PMID   27441006.
  12. Wollmann, null (1998). "Intrauterine growth restriction: definition and etiology". Hormone Research. 49 (# Suppl 2): 1–6. doi:10.1159/000053079. ISSN   1423-0046. PMID   9716819. S2CID   37436666.
  13. 1 2 Sharma, Deepak; Shastri, Sweta; Farahbakhsh, Nazanin; Sharma, Pradeep (December 2016). "Intrauterine growth restriction - part 1". The Journal of Maternal-Fetal & Neonatal Medicine. 29 (24): 3977–3987. doi:10.3109/14767058.2016.1152249. ISSN   1476-4954. PMID   26856409. S2CID   29439634.
  14. Saccone G, Berghella V, Sarno L, Maruotti GM, Cetin I, Greco L, Khashan AS, McCarthy F, Martinelli D, Fortunato F, Martinelli P (October 9, 2015). "Celiac disease and obstetric complications: a systematic review and meta-analysis". Am J Obstet Gynecol. 214 (2): 225–34. doi:10.1016/j.ajog.2015.09.080. hdl: 11369/330101 . PMID   26432464.
  15. Tong, Zhao; Xiaowen, Zhang; Baomin, Chen; Aihua, Liu; Yingying, Zhou; Weiping, Teng; Zhongyan, Shan (2016-05-01). "The Effect of Subclinical Maternal Thyroid Dysfunction and Autoimmunity on Intrauterine Growth Restriction: A Systematic Review and Meta-Analysis". Medicine. 95 (19): e3677. doi:10.1097/MD.0000000000003677. ISSN   1536-5964. PMC   4902545 . PMID   27175703.
  16. Flamant, C.; Gascoin, G. (2013-12-01). "Devenir précoce et prise en charge néonatale du nouveau-né petit pour l'âge gestationnel". Journal de Gynécologie Obstétrique et Biologie de la Reproduction. 42 (8): 985–995. doi:10.1016/j.jgyn.2013.09.020. ISSN   0368-2315. PMID   24210715.
  17. Steurer, Martina A.; Jelliffe-Pawlowski, Laura L.; Baer, Rebecca J.; Partridge, J. Colin; Rogers, Elizabeth E.; Keller, Roberta L. (2017-01-01). "Persistent Pulmonary Hypertension of the Newborn in Late Preterm and Term Infants in California". Pediatrics. 139 (1): e20161165. doi: 10.1542/peds.2016-1165 . ISSN   0031-4005. PMID   27940508.
  18. Cohen, Emily; Wong, Flora Y.; Horne, Rosemary S. C.; Yiallourou, Stephanie R. (June 2016). "Intrauterine growth restriction: impact on cardiovascular development and function throughout infancy". Pediatric Research. 79 (6): 821–830. doi: 10.1038/pr.2016.24 . ISSN   1530-0447. PMID   26866903.
  19. 1 2 3 4 5 Malhotra, Atul; Allison, Beth J.; Castillo-Melendez, Margie; Jenkin, Graham; Polglase, Graeme R.; Miller, Suzanne L. (2019). "Neonatal Morbidities of Fetal Growth Restriction: Pathophysiology and Impact". Frontiers in Endocrinology. 10: 55. doi: 10.3389/fendo.2019.00055 . ISSN   1664-2392. PMC   6374308 . PMID   30792696.
  20. Colella, Marina; Frérot, Alice; Novais, Aline Rideau Batista; Baud, Olivier (2018). "Neonatal and Long-Term Consequences of Fetal Growth Restriction". Current Pediatric Reviews. 14 (4): 212–218. doi:10.2174/1573396314666180712114531. ISSN   1875-6336. PMC   6416241 . PMID   29998808.
  21. Keunen, K.; Kersbergen, K. J.; Groenendaal, F.; Isgum, I.; de Vries, L. S.; Benders, M. J. N. L. (March 2012). "Brain tissue volumes in preterm infants: prematurity, perinatal risk factors and neurodevelopmental outcome: a systematic review". The Journal of Maternal-Fetal & Neonatal Medicine. 25 (Suppl 1): 89–100. doi:10.3109/14767058.2012.664343. ISSN   1476-4954. PMID   22348253. S2CID   12698320.
  22. Batalle D, Eixarch E, Figueras F, Muñoz-Moreno E, Bargallo N, Illa M, Acosta-Rojas R, Amat-Roldan I, Gratacos E (2012). "Altered small-world topology of structural brain networks in infants with intrauterine growth restriction and its association with later neurodevelopmental outcome". NeuroImage. 60 (2): 1352–66. doi:10.1016/j.neuroimage.2012.01.059. PMID   22281673. S2CID   1242147.
  23. Geva R, Eshel R, Leitner Y, Valevski AF, Harel S (2006). "Neuropsychological Outcome of Children With Intrauterine Growth Restriction: A 9-Year Prospective Study". Pediatrics. 118 (1): 91–100. doi:10.1542/peds.2005-2343. PMID   16818553. S2CID   11394000.
  24. Black LS, deRegnier RA, Long J, Georgieff MK, Nelson CA (November 2004). "Electrographic imaging of recognition memory in 34-38 week gestation intrauterine growth restricted newborns". Experimental Neurology. 190 (Suppl 1): S72–83. doi:10.1016/j.expneurol.2004.05.031. PMID   15498545. S2CID   7742685.
  25. 1 2 3 Lees, C. C.; Stampalija, T.; Baschat, A. A.; Silva Costa, F.; Ferrazzi, E.; Figueras, F.; Hecher, K.; Kingdom, J.; Poon, L. C.; Salomon, L. J.; Unterscheider, J. (August 2020). "ISUOG Practice Guidelines: diagnosis and management of small‐for‐gestational‐age fetus and fetal growth restriction". Ultrasound in Obstetrics & Gynecology. 56 (2): 298–312. doi:10.1002/uog.22134. hdl: 11343/276085 . ISSN   0960-7692. PMID   32738107. S2CID   220909268.
  26. 1 2 Sharma D, Shastri S, Sharma P (2016). "Intrauterine Growth Restriction: Antenatal and Postnatal Aspects". Clinical Medicine Insights. Pediatrics. 10: 67–83. doi:10.4137/CMPed.S40070. PMC   4946587 . PMID   27441006.
  27. McCall, CA; Grimes, DA; Lyerly, AD (June 2013). ""Therapeutic" bed rest in pregnancy: unethical and unsupported by data". Obstetrics and Gynecology. 121 (6): 1305–8. doi:10.1097/AOG.0b013e318293f12f. PMID   23812466. S2CID   9069311.
  28. "Antenatal Corticosteroid Therapy for Fetal Maturation". Obstetric Anesthesia Digest. 29 (1): 11. March 2009. doi:10.1097/01.aoa.0000344672.12959.0d. ISSN   0275-665X.
  29. "Magnesium Sulphate Given Before Very-Preterm Birth to Protect Infant Brain: The Randomised Controlled PREMAG Trial". Obstetric Anesthesia Digest. 27 (4): 175–176. December 2007. doi:10.1097/01.aoa.0000302277.08830.d0. ISSN   0275-665X.
  30. Carlo L. Acerini (2013). Oxford Handbook of Paediatrics. Robert J. McClure, Robert C. Tasker. OUP Oxford. ISBN   9780191015885. OCLC   1223311499.
  31. Gilbert, William M.; Danielsen, Beate (2003). "Pregnancy outcomes associated with intrauterine growth restriction". American Journal of Obstetrics and Gynecology. 188 (6): 1596–1601. doi:10.1067/mob.2003.384. ISSN   0002-9378. PMID   12824998.
  32. Hoe, Francis M.; Thornton, Paul S.; Wanner, Laura A.; Steinkrauss, Linda; Simmons, Rebecca A.; Stanley, Charles A. (February 2006). "Clinical features and insulin regulation in infants with a syndrome of prolonged neonatal hyperinsulinism". The Journal of Pediatrics. 148 (2): 207–212. doi:10.1016/j.jpeds.2005.10.002. PMID   16492430.
  33. Hyman, Sharon J.; Novoa, Yeray; Holzman, Ian (October 2011). "Perinatal Endocrinology: Common Endocrine Disorders in the Sick and Premature Newborn". Pediatric Clinics of North America. 58 (5): 1083–1098. doi:10.1016/j.pcl.2011.07.003. PMID   21981950.
  34. Mukhopadhyay, Dhriti; Weaver, Laura; Tobin, Richard; Henderson, Stephanie; Beeram, Madhava; Newell-Rogers, M. Karen; Perger, Lena (May 2014). "Intrauterine growth restriction and prematurity influence regulatory T cell development in newborns". Journal of Pediatric Surgery. 49 (5): 727–732. doi:10.1016/j.jpedsurg.2014.02.055. ISSN   0022-3468. PMID   24851757.
  35. Barker, D. J. P., ed. (1992). Fetal and infant origins of adult disease. London: British Medical Journal. ISBN   978-0-7279-0743-1.
  36. Karlberg, J.; Albertsson-Wikland, K. (1995). "Growth in Full- Term Small-for-Gestational-Age Infants: From Birth to Final Height". Pediatric Research. 38 (5): 733–739. doi: 10.1203/00006450-199511000-00017 . ISSN   1530-0447. PMID   8552442.
  37. Løhaugen, Gro C.C.; Østgård, Heidi Furre; Andreassen, Silje; Jacobsen, Geir W.; Vik, Torstein; Brubakk, Ann-Mari; Skranes, Jon; Martinussen, Marit (2013). "Small for Gestational Age and Intrauterine Growth Restriction Decreases Cognitive Function in Young Adults". The Journal of Pediatrics. 163 (2): 447–453.e1. doi:10.1016/j.jpeds.2013.01.060. ISSN   0022-3476. PMID   23453550.
  38. Lundgren, Ester Maria; Cnattingius, Sven; Jonsson, Björn; Tuvemo, Torsten (2001). "Intellectual and Psychological Performance in Males Born Small for Gestational Age With and Without Catch-Up Growth". Pediatric Research. 50 (1): 91–96. doi: 10.1203/00006450-200107000-00017 . ISSN   1530-0447. PMID   11420424.
  39. McMillen, I. C.; Muhlhausler, B. S.; Duffield, J. A.; Yuen, B. S. J. (2004). "Prenatal programming of postnatal obesity: fetal nutrition and the regulation of leptin synthesis and secretion before birth". Proceedings of the Nutrition Society. 63 (3): 405–412. doi:10.1079/PNS2004370. hdl: 2440/3152 . ISSN   0029-6651. PMID   15373950. S2CID   29901966.
  40. Langley-Evans, Simon C.; Gardner, David S.; Jackson, Alan A. (1996-06-01). "Maternal Protein Restriction Influences the Programming of the Rat Hypothalamic-Pituitary-Adrenal Axis". The Journal of Nutrition. 126 (6): 1578–1585. doi: 10.1093/jn/126.6.1578 . ISSN   0022-3166. PMID   8648431.
  41. Bacchetta, Justine; Harambat, Jérôme; Dubourg, Laurence; Guy, Brigitte; Liutkus, Aurélia; Canterino, Isabelle; Kassaï, Behrouz; Putet, Guy; Cochat, Pierre (2009). "Both extrauterine and intrauterine growth restriction impair renal function in children born very preterm". Kidney International. 76 (4): 445–452. doi: 10.1038/ki.2009.201 . ISSN   0085-2538. PMID   19516242.
  42. 1 2 Vatnick I, Ignotz G, McBride BW, Bell AW (September 1991). "Effect of heat stress on ovine placental growth in early pregnancy". Journal of Developmental Physiology. 16 (3): 163–6. PMID   1797923.
  43. Bell A. W.; McBride B. W.; Slepetis R.; Early R. J.; Currie W. B. (1989). "Chronic Heat Stress and Prenatal Development in Sheep: I. Conceptus Growth and Maternal Plasma Hormones and Metabolites". Journal of Animal Science. 67 (12): 3289–3299. doi:10.2527/jas1989.67123289x. PMID   2613577. S2CID   9440955.
  44. 1 2 Regnault TR, Orbus RJ, Battaglia FC, Wilkening RB, Anthony RV (September 1999). "Altered arterial concentrations of placental hormones during maximal placental growth in a model of placental insufficiency". The Journal of Endocrinology. 162 (3): 433–42. doi: 10.1677/joe.0.1620433 . PMID   10467235.
  45. Ehrhardt RA, Bell AW (December 1995). "Growth and metabolism of the ovine placenta during mid-gestation". Placenta. 16 (8): 727–41. doi: 10.1016/0143-4004(95)90016-0 . PMID   8710803.
  46. Rattray PV, Garrett WN, East NE, Hinman N (March 1974). "Growth, development and composition of the ovine conceptus and mammary gland during pregnancy". Journal of Animal Science. 38 (3): 613–26. doi: 10.2527/jas1974.383613x . PMID   4819552.
  47. Wallace J. M. (2000). "Nutrient partitioning during pregnancy: adverse gestational outcome in overnourished adolescent dams". Proc. Nutr. Soc. 59 (1): 107–117. doi: 10.1017/s0029665100000136 . PMID   10828180.
  48. 1 2 3 Wallace J. M.; Regnault T. R. H.; Limesand S. W.; Hay Jr.; Anthony R. V. (2005). "Investigating the causes of low birth weights in contrasting ovine paradigms". J. Physiol. 565 (Pt 1): 19–26. doi:10.1113/jphysiol.2004.082032. PMC   1464509 . PMID   15774527.
  49. Morris ST, Kenyon PR, West DM (2010). "Effect of hogget nutrition in pregnancy on lamb birthweight and survival to weaning". New Zealand Journal of Agricultural Research. 48 (2): 165–175. doi: 10.1080/00288233.2005.9513647 . ISSN   0028-8233.
  50. Bell AW, Wilkening RB, Meschia G (February 1987). "Some aspects of placental function in chronically heat-stressed ewes". Journal of Developmental Physiology. 9 (1): 17–29. PMID   3559063.
  51. Thureen PJ, Trembler KA, Meschia G, Makowski EL, Wilkening RB (September 1992). "Placental glucose transport in heat-induced fetal growth retardation". The American Journal of Physiology. 263 (3 Pt 2): R578–85. doi:10.1152/ajpregu.1992.263.3.R578. PMID   1415644.