2. Defining disorders of growth requires relating a
given achieved growth to an expected growth.
Within genetically set limits, the actual fetal growth
judged by Fetal weight is determined by the
- genetic growth potential which varies from race to
race and individual to individual ,
- the health of the fetus with good fetal circulation,
- the capacity of the mother to supply adequate
quality
and quantities of substrates ( O2 , glucose,
aminoacids
etc) required for growth,
3. ď˝ With a prevalence of the 5â8% in the general
population, IUGR can complicate 10% to 15% of
all pregnancies .
- However, only 20â30% of these fetuses are
small because of a pathological restriction of their
growth (PFGR) and a majority are normal SGA
-IUGR represents the second cause of perinatal
mortality, after prematurity
-It is related to an increased risk of perinatal
complication as hypoxemia, low Apgar scores,
and cord blood acidemia, with possible negative
effects for neonatal outcome.
-It is associated with increased risk of
neurological, cardiovascular and metabolic
4. In practice, due to error in estimating gestational age, inaccuracy
in weight estimation, and variation in true genetic potential, there
will be no cut off that correctly separates normal and abnormal
IMPORTANT TERMS IN FETAL GROWTH
DISORDER
SGA simply refers to a weight for gestation
below a given threshold, but a significant
proportion of smallness is due to
constitutional or physiological causes, The
most commonly used definition of SGA is a
birth weight below the 10th percentile for
gestational age.
IUGR SIGNIFIES THE PATHOLOGICAL CAUSE OF
SAME CUTOFF
5. Endocrine regulation of fetal growth â
IGF -1 IGF -2
Placental regulation of fetal growth â
Implantation and early placentation play
crucial role
Genomic imprinting and fetal growth
9. Lack of substrate and inability to reach genetic
potential
⢠Genetic abnormalities, including:
⢠trisomy 13, 18, or 21
⢠turnerâs syndrome
⢠triploidy.
⢠Congenital abnormalities, including:
⢠cardiac, e.g. TOF, transposition of the great vessels
⢠gastroschisis.
⢠Congenital infection, including:
⢠CMV
⢠rubella
⢠toxoplasmosis.
⢠Multiple pregnancy
10. -Type I or symmetric FGR corresponds to fetuses
that are symmetrically small and have normal H/A
and F/A ratios.
Type II or asymmetric FGR corresponds to fetuses
that have an AC that is smaller than the HC and the
FL resulting in abnormally high H/A and F/A ratios.
Type III or intermediate FGR corresponds to fetuses
that are initially symmetric but become asymmetric
later in the pregnancy.
11. âIntrinsicâ- FGR occurs when the fetuses are
small due to fetal conditions such as viral
infections or chromosomal abnormalities.
âExtrinsicâ -FGR occurs when the growth failure
is due to an element outside of the fetus such as a
placental condition or a maternal disease.
âCombinedâ- FGR occurs when there are extrinsic
and intrinsic factors causing the growth failure
and
âIdiopathicâ -FGR when the cause of the fetal
12. BASED ON DOPPLER FINDINGS NOT BIRTHWEIGHT
SOLELY
1) Small for gestational age (SGA) refers to those
small fetuses with no discernible pathology and
with normal umbilical artery and middle cerebral
artery Doppler results;
2) Growth-restriction refers to small fetuses with
recognizable pathology and abnormal Doppler
studies; and
3) Idiopathic growth restriction applies to small
fetuses with no discernable pathology and
abnormal Doppler studies.28
13. ď˝ Early-onset FGR represents 20â30% of all FGR
and is associated with gestational
hypertension and/or pre-eclampsia in up to
70%.
Late-onset FGR, which represents
approximately 70â80% of cases of FGR, shows
a weaker association with hypertensive
disorders of the pregnancy, roughly 10%
14.
15.
16. 1) Maternal socio-economic condition and nutritional
status
2) Maternal smoking , alcohol intake , teratogen intake or
substance abuse in past and present
3) Previous history of growth restriction or still birth
- 50% increased risk of severe growth restriction
- Stillbirths before 32 weeksâ gestation have a
particularly strong association with IUGR.
4) Medical disorders
5) Diabetes -Preeclampsia is observed in 15-20% of
pregnancies complicated by type 1 diabetes mellitus
without nephropathy and approximately 50% in the
presence of nephropathy.
6) Low PAPP-A , two vessel cord and multiple pregnancy
7) IVF pregnancy
17. Biochemical markers. In the first trimester, an
unexplained low pregnancy-associated plasma protein
A or human chorionic gonadotropin (hCG) is
associated with an increased risk of placental-related
diseases such as IUGR or preeclampsia.
Early growth restriction. Low first-trimester
measurement of crown-rump length in pregnancies
dated by the last menstrual period is also linked with
FGR.
Slow growth between the first and second trimester is
able to identify a subgroup of slow-growing babies that
are at increased risk of perinatal death before 34
weeksâ gestation, in most cases with growth restriction.
18. Biochemical markers - an unexplained elevation of
serum alpha-fetoprotein, hCG, or inhibin-A is also
associated with these adverse outcomes.
Uterine artery Dopplers -. Uterine Doppler
evaluation in the second or first trimester has
been proposed as a screening tool for early-onset
IUGR,with detection rates of about 75% and 25%,
respectively, for a false-positive rate of 5-10%.
These sensitivities are higher for predicting early
IUGR associated with preeclampsia and lower for
late IUGR.
SCREENING IN SECOND
TRIMESTER
Different strategies combining maternal risk
factors, blood pressure, and biochemical
markers have been published with detection
rates greater than 90% for early-onset
preeclampsia and associated IUGR
19. Serial fundal height assessment
Routine/intermittent third-trimester ultrasound
biometry
Serial ultrasound biometry. For pregnancies at
risk due to past or current situation , serial
assessment of estimated fetal weight or
abdominal circumference is the best predictor of
FGR as assessed by neonatal morphometry.
Therefore, serial biometry is the recommended
gold standard
20. Serial ultrasound biometry. For pregnancies at risk, serial
assessment of estimated fetal weight or abdominal
circumference is the best predictor of FGR as assessed by
neonatal morphometry
Amniotic fluid. A metaanalysis 132 of 18 randomized
studies demonstrated that an amniotic fluid index of less
than 5 is associated with abnormal 5 minute Apgar score
but failed to demonstrate an association with acidosis.
Longitudinal studies in early-onset IUGR fetuses have
shown that the amniotic fluid index progressively
Routine/intermittent third-trimester ultrasound biometry.
Sensitivity of AC for detecting a birthweight less than the
10th centile ranges from 48% to 87%, with specificity from
69% to 85%. For estimated fetal weight, sensitivities of 25-
100% have been reported, with a specificity of 69-97%.
21. First, the standard is customized for sex as well as
maternal characteristics such as height, weight,
parity, and ethnic origin based on-one size does not
fit all theory.
Second, pathological factors such as smoking,
hypertension, diabetes, and preterm delivery are
excluded to predict the optimum weight that a baby
can reach at the end of a normal pregnancy.
Third, the term optimal weight and associated
normal range is projected backward for all
gestational age points, using an ultrasound growth
based proportionality curve
It is calculated by computer software
CUSTOMISED GROWTH CHART â
THREE PRINCIPLES
24. For the practicing obstetrician, these problems
can be summarized in following five important
questions:
?? How to recognize that the fetus is small
?? How to differentiate between the fetuses that
are small and healthy and the fetuses that have
pathological growth restriction?
?? Which is the appropriate fetal surveillance
method and follow up interval ?
?? How to manage the pregnancies afflicted by
pathological fetal growth restriction (PFGR) as per
their staging of deterioration ?
?? How to optimize the timing and mode of
40. ANTEPARTUM COMPLICATIONS are an increased
incidence of stillbirth, oligohydramnios, and
antepartum fetal distress.
INTRAPARTUM COMPLICATIONS are fetal
hypoxia, acidosis, and high rate of cesarean
delivery.
NEONATAL COMPLICATIONS are multiple and
include hypoglycemia, hyperbilirubinemia,
meconium aspiration, persistent fetal circulation,
hypoxic-ischemic encephalopathy, hypocalcemia,
41. OXYGEN â No role
PLASMAVOLUME EXPANDERS â no role
BETA MIMETICS - Larger, well-designed studies are needed
to evaluate the effects of betamimetics on fetal growth.
Since there is potential for adverse effects due to the
pharmacological characteristics of this group of drugs
BED REST IN HOSPITAL- There is not enough evidence to
evaluate the use of a bed rest in hospital policy for women
with suspected impaired fetal growth.
AMNIOINFUSION - Amnioinfusion with saline solution
should be one of the initial steps in the intrapartum
management of the PFGR fetus with decreased amniotic
fluid volume or early MSL.
SILDENAFIL ( NO promoter ) â Phosphodiesterase
inhibitors. The enzyme phosphodiesterase breaks down
cGMP, an enzyme critical to the effect of NO. But sildenafil
42. - Always determine the correct gestational age . - Patients
with high-risk factors, unreliable dates, and abnormal or
difficult to assess uterine growth are at risk for carrying
small fetuses.
-In the majority of cases the clinical findings and
ultrasound measurements allow only the diagnosis of
âsmall fetus.â The majority of small fetuses are healthy.
Only a modest proportion of small fetuses are truly
undernourished or PFGR.
- To distinguish between fetuses that are small and healthy
and PFGR it is necessary to use serial growth charts and
Doppler assessment of the uterine, umbilical, and mid
cerebral artery resistance.Dopplers are not only diagnostic
43. - Uterine artery, UA, and MCA Doppler do not identify all
PFGR fetuses. Doppler technology is exclusively for the
identification of PFGR because of placental insufficiency.
Small fetal size in the presence of normal uterine,
umbilical, and midcerebral Doppler rules out placental
insufficiency .
- The most important surveillance tests to follow the
PFGR fetus are the FHR monitoring by CTG and the
umbilical and cerebral Doppler. As long as the FHR
monitoring is normal and the Doppler does not show fetal
decompensation (ADF or RDF) expectant management is
adequate.
- The placentas of all PFGR babies should be examined by
a competent placental pathologist. In many cases the
placenta will provide evidence regarding the etiology of
the problem.
-The earlier in gestation IUGR is detected, the greater the
possibility of developmental problems later in life. The
44.
45. Staging system and management
¡ Stage 0 SGA fetuses have a good prognosis. They are managed as outpatient with Doppler assessment every
2 weeks. If the Doppler remains normal, delivery is recommended at term. If the Doppler becomes abnormal, these
fetuses are managed as Stage I IUGR fetuses.
¡ Stage I IUGR fetuses are considered to have mild growth restriction, and affected mothers who are without
preeclampsia are usually managed as outpatients. Antenatal corticosteroids should be given at time of diagnosis. In
these fetuses, twice-weekly antenatal testing is recommended. If the non-stress testing (NST) remains reactive and
the AFI remains >5.0 cm, delivery is recommended at 37 weeksâ gestation. If the umbilical artery Doppler becomes
absent, these fetuses should be managed as Stage II IUGR.
¡ Stage II IUGR fetuses should be managed as inpatients. During hospital admission, the fetuses should undergo
daily antenatal testing with twice-daily NST and daily biophysical profile (BPP). If the NST remains reassuring and
the BPP score remains between 6 and 8 of 8, continuation of expectant management is recommended. In addition,
antenatal corticosteroids should be given at time of diagnosis. Delivery is recommended at 34 weeks. If any of the
aforementioned NSTs become non-reassuring or if the BPP score is 4 of 8 on 2 occasions at least 4 hours apart,
immediate delivery is recommended. Delivery should occur via cesarean delivery because fetuses with an
absent/reversed flow of the umbilical artery will not tolerate labor induction.
¡ Stage III IUGR fetuses are managed the same as Stage II except for delivery at 32 weeksâ gestation, regardless
of gestational age at time of diagnosis. As with Stage I and II, antenatal corticosteroids should be given at time of
diagnosis.
The advantage of the above scoring system is its simplicity. Only fetal biometry, sonographic interrogation of three
fetal vessels, and the amniotic fluid index are needed. It also allows classification of all small fetuses. Of note is that
if the umbilical artery and middle cerebral artery Doppler is normal, it is determination of flow velocity waveforms of
the ductus venosus is unnecessary because it will be normal as well. The presence of IUGR in the setting of
preeclampsia should not deter standard management of preeclampsia.
It is important to note the rate of mortality in the staging system.29 No deaths occurred in Stage 0 or Stage I fetuses,
whereas the mortality for stage III fetuses is high (50% if there was reversal of flow in the ductus venosus; 85%
mortality was observed when reversal of flow in the ductus venosus was present in combination with one of the other
parameters that characterize stage III), whereas the mortality in stage II IUGR fetuses was intermediate between
stages I and III (Figure 4). Also, studies have shown that fetuses can survive for days or weeks with reversal of flow
in the ductus venosus.29 A recent preliminary study reported that fetuses with reversal of flow in the ductus venosus
will not necessarily be acidemic at birth.30 In addition, the majority of affected pregnancies have an AFI <5 cm before
Hinweis der Redaktion
Fetal weight is determined by the genetic growth potential, the health of the fetus, the capacity of the mother to supply adequate quality and quantities of substrates required for growth, and the ability of the placenta to transport these nutritional substrates to the fetus. The genetic growth potential varies from race to race and from individual to individual and this variation is evident in population studies of healthy term newborns showing a symmetrical distribution curve of their birth weights. Normal fetuses at either extreme of this normal biological distribution curve will be combined with others whose growth has been restricted or accelerated due to pathological influences The most important are oxygen, glucose, and amino acids.Oxygen crosses the placenta by simple diffusion and is necessary for the formation of chemical energy in the form ofadenosine triphosphate (ATP). Glucose crosses the placenta by facilitated diffusion and its concentration in the fetusis determined by the maternal plasma glucose levels.Glucose is utilized in the production of energy and in the provision of carbon-building blocks for the synthesis of lipids, glycogen, nucleotides, and other molecules. Amino acids cross the placenta by active transport and are essential for the synthesis of proteins. Any persistent decrease inthe availability of these substrates will limit the ability ofthe fetus to reach his/her growth potential, and a severe substrate deficiency may threaten the ability of the fetus to survive. The availability of substrates necessary for fetalgrowth may be limited by pathological conditions affecting the placenta, the fetus, and the mother.
Maternal conditions associated with PFGR interfere with fetal growth by one of the three mechanisms:1. Causing or aggravating placental vascular insufficiency2. Limiting the availability of substrates required for fetal growth and development or3. Transferring to the fetus substances that affect the fetal growth
The most common causes (75â80% of the cases) ofPFGR are abnormalities of the placenta, affecting thematernal or the fetal circulation or both. In the majorityof these cases, there is diminished maternal uteroplacental blood flow caused by insufficient or incomplete trophoblastic invasion of the spiral arteries in the placentalbed. Under normal conditions, trophoblastic cells firstinfiltrate the decidua and then the myometrial portion ofthe spiral arteries, destroying the elastic and muscularlayers and replacing them with fibrinoid material.Another feature of abnormal placentation is the deposition of lipoprotein and the infiltration by foamymacrophages of the vascular wall, giving the appearanceof accelerated atherosclerosis. The rigid vessel walls aretransformed into flaccid sac-like structures that canaccommodate the increased uteroplacental blood flowthat occurs during pregnancy. These transformed spiralarteries are not affected by maternal vasoregulatorymechanisms. The initial phase of the trophoblastic invasion of the spiral arteries usually ends by the 16th weekof gestation, but in many cases completion of the adaptative changes does not occur until 20â22 weeks. Whenplacentation is abnormal, trophoblastic invasion islargely confined to the decidual layer with absent orincomplete changes in the myometrial portion of the spiral and radial arteries. The presence of spiral and radialarteries with intact muscular and elastic layers causesincreased vascular resistance and decreased blood flowto the intervillous space, restricting the maternal capacity to provide oxygen and nutrients to the fetus. Also, the vessels with absent or incomplete transformation remainreactive to vasoactive substances produced or ingestedby the mother. This placentation defect is not exclusiveof FGR and is also found in placentas of women withpreeclampsia, preterm labor, and preterm prematurerupture of the fetal membranes. Placentalinfarcts are present in up to 10% of normal pregnancies andthey probably result from the hypercoagulability of pregnancy combined with the slow blood flow through the intervillous space. The presence of multiple infarcts is stronglysuggestive of the possibility of congenital or acquired maternal thrombophilia. Antiphospholipid antibodies are themost common cause of acquired thrombophilia and factorV Leiden mutation, prothrombin promoter mutation,homozygosity for the methylene-tetra-hydro-folate reductase C677T mutation, and decreased protein S activity arethe most common congenitally acquired thrombophilicstates.A lesion in the maternal side associated with PFGR ismassive perivillous fibrin deposition. In these cases theintervillous space is occupied by fibrin and the villi embedded within the fibrinous mass are nonfunctional. In onestudy the incidence of PFGR in cases of massive perivillousfibrin deposition was 62.9% (Fuke et al., 1994). This lesionis also present in some cases of fetal demise and is stronglysuggestive of the possibility of maternal thrombophilia.Maternal floor infarction is another placental lesionassociated with PFGR and fetal demise. Pathologically,this condition is characterized by massive deposition offibrin in the maternal floor of the placenta encasing thecontiguous villi that become necrotic or atrophic. Thislesion is apparent macroscopically and can be identifiedeasily by looking at the maternal side of the placentawhich will be covered by pale, glassy, smooth tissue withan appearance that vaguely resembles the surface of abrain. Maternal floor infarct is found in 5 per 1000 to 9per 10,000 births. It is associated with PFGR in morethan 50% of cases and is a common finding in cases offetal death (Mandsager et al., 1994). Unfortunately, thiscondition frequently reoccurs in successive pregnancies.The pathophysiological basis for maternal floor infarct isunknown but maternal thrombophilia is a good possibility and should be researched systematically. Some investigators consider that maternal floor infarction and massiveperivillous fibrin deposition are related conditions(Katzman et al., 2002).Other placental lesions associated with PFGR arechronic villitis, hemorrhagic endovasculitis, and confinedplacental mosaicism. Lymphocytic and histiocytic infiltration of the villi are the markers of chronic villitis (Althabeand Labarrere, 1985), a nonspecific lesion that may occurin isolation but frequently is associated with vascularlesions in the maternal or fetal side of the placenta. Chronicvillitis may be immunological or viral in origin. When cellinfiltration by plasma cells occurs, the possibility of infection by cytomegalic virus is high. Chronic villitis occurs inapproximately 8% of normal pregnancies but the incidenceincreases three- to fourfold in cases of PFGR. Pathologicalfetal growth restriction is present in approximately 30%of patients with chronic villitis.Hemorrhagic endovasculitis is another lesion associatedwith poor pregnancy outcome and is histologically characterized by the presence of numerous extravascular erythrocytes infiltrating the villi. It is generally believed that hemorrhagic endovasculitis is another histological manifestation of maternal/fetal thrombophilia. Both chronic villitisand hemorrhagic endovasculitis are frequently present inplacentas from women with preeclampsia.In cases of confined placental mosaicism, the chromosomal composition of the placenta is not the same as that ofthe fetus. In these cases the placenta is usually trisomic andthe fetus has a normal karyotype but inherits both homologous chromosomes from one of the parents. Most commonly the placenta is trisomic for chromosome 16 but upto 12 other chromosomes could be involved. Most likelythe zygote is originally trisomic with subsequent expulsionof one of the trisomic chromosomes from the embryonicbut not from the trophoblastic tissue (Robinson et al.,1997). Confined placental mosaicism and fetal uniparentaldisomy is a condition associated with severe PFGR but mayalso occur in newborns with normal weight and in somethat are large for gestational age.Clotting and thrombosis may also be present in thefetal side of the placental circulation. In these cases theintravascular clotting affects the chorionic stem vessels,causing an infarct with avascular fibrous villi in the distribution territory of the affected vessel. This lesion hasbeen named fetal thrombotic vasculopathy (Redline andPappin, 1995). In many cases the lesions in the fetal circulation occur simultaneously with infarcts or decidualCHAPTER 4 FETAL GROWTH RESTRICTION 109vasculopathy in the maternal side of the placenta but inother cases they may occur without apparent maternalside lesions. In any case, the presence of fetal thromboticvasculopathy has a strong association with poor pregnancy outcome (Arias et al., 1998). Of particular importanceis the possibility of an association between this placentallesion and thromboembolic lesions in the fetal brain(Rayne and Kraus, 1993).Placental vascular insufficiency and impaired fetalgrowth of one or more fetuses are a relatively commonfinding in multifetal pregnancies. When the restriction ingrowth affects only one of the fetuses is named âselectiveFGRâ condition that may occur in up to 21% of multifetal pregnancy. The problem occurs more frequently intwins with monochorionic placentation. Abnormal insertion of the umbilical cord, torsion of the cord, hemangiomas of the placenta, and placenta previa are situationsalso frequently associated with selective FGR. The overallprevalence of these abnormalities is low.
The frequency of congenitally abnormal newborns among severely affected PFGR fetuses is approximately 10%. The majority of these genetically affected babies have asymmetric measurements in prenatal ultrasound examination with the head being larger than the abdomen. PFGR is common in chromosomal disorders, especially in somatic trisomies. It also occurs in patients with familial dysautonomy, osteogenesis imperfecta, and other multifactorial disorders.Single gene mutations do not affect fetal growth as much as do chromosomal defects. The possibility of a fetal congenital disorder should always be considered in patients with âidiopathicâ or âunexplainedâ FGR. In a study of more than 13,000 malformed infants bornin Atlanta (Khoury et al., 1988) the overall frequency of PFGR was 22.3%. The most common abnormalities associated with PFGR were chromosomal, particularly trisomy 18. The mechanism of fetal growth impairment secondary to genetic syndromes is unknown but it is possiblethat chromosomal defects cause alterations in placental function, resulting in fetal malnutrition. A large number of fetuses affected by genetic conditions can be detected by a comprehensive or genetic ultrasound examination.Fetal infections are not a common cause of PFGR.Bacterial infections usually have acute courses and cause preterm labor, preterm rupture of membranes, or fetal death. Viral infections on the other hand may be chronic and affect fetal growth. The viral infections associated with impaired fetal growth are congenital rubella, cytomegalic virus, congenital varicella, human immunodeficiency virus, and acute herpes simplex virus infection
The problems in diagnosing and managing pregnancieswith impaired fetal growth are substantial. This is due tothe confusion between fetuses that are small and healthyand those who have a pathological restriction in theirgrowth, to our inability to know what is the growthpotential of a given fetus, to the occurrence of FGR inpatients without recognizable high-risk factors, to theproliferation of measurements to assess fetal growth, tothe difficulties in estimating gestational age, and to different opinions about the ideal time to deliver these smallfetuses.
Fig. 2. Fetal deterioration and monitoring in early-severe FGR. Placental disease affects a large proportion of the placenta, and this isreflected in changes in the UA Doppler in a high proportion ofcases. The figure depicts in a schematic and simplified fashion thepathophysiologic progression with the main adaptation/consequence in placental-fetal physiology, and the accompanying cascade of changes in Doppler parameters. The sequence illustrates theaverage temporal relation among changes in parameters, but theactual duration of deterioration is influenced by severity. Regardless of the velocity of progression, in the absence of accompanyingPE this sequence is relatively constant, particularly as regards endstage signs and the likelihood of serious injury/death. However,severe PE may distort the natural history and fetal deteriorationmay occur unexpectedly at any time (see text for abbreviations).
Fig. 3. Fetal deterioration and monitoring in late-mild FGR. Placental disease is mild and UA Doppler values are not elevatedabove the 95th centile. The effects of fetal adaptation are best detected by the CPR, which can pick up mild changes in the AU andMCA Doppler. An important fraction of cases do not progress tobaseline hypoxia so that they remain only with abnormal CPR.Once baseline hypoxia is established, placental reserve is minimaland progression to fetal deterioration may occur quickly, as suggested by the high risk of severe deterioration or intrauterine fetaldeath after 37 weeks in these cases, possibly due to a combinationof a higher susceptibility to hypoxia of the term-mature fetus andthe more common presence of contractions at term (see text forabbreviations).
Stage I Fetal Growth Restriction (Severe Smallness orMild Placental Insufficiency). Either UtA, UA or MCADoppler, or the CPR are abnormal. In the absence of other abnormalities, evidence suggests a low risk of fetal deterioration before term. Labor induction beyond 37 weeksis acceptable, but the risk of intrapartum fetal distress isincreased [44]. Cervical induction with Foley catheter isalso recommended. Weekly monitoring seems reasonable.Stage II Fetal Growth Restriction (Severe Placental Insufficiency). This stage is defined by UA absent-end diastolic velocity (AEDV) or reverse AoI. Although evidencefor UA AEDV is stronger than that for AoI, observational evidence suggests an association between the latter toabnormal neurodevelopment, so that both criteria become a single category. Delivery should be recommendedafter 34 weeks. The risk of emergent cesarean section atlabor induction exceeds 50%, and, therefore, elective cesarean section is a reasonable option. Monitoring twice aweek is recommended.Stage III Fetal Growth Restriction (Advanced Fetal Deterioration, Low-Suspicion Signs of Fetal Acidosis). Thestage is defined by reverse absent-end diastolic velocity(REDV) or DV PI >95th centile. There is an associationwith a higher risk of stillbirth and poorer neurologicaloutcome. However, since signs suggesting a very high riskof stillbirth within days are not present yet, it seems reasonable to delay elective delivery to reduce as possible theeffects of severe prematurity. We suggest delivery shouldbe recommended by cesarean section after 30 weeks.Monitoring every 24â48 h is recommended.Stage IV Fetal Growth Restriction (High Suspicion ofFetal Acidosis and High Risk of Fetal Death). There arespontaneous FHR decelerations, reduced STV (<3 ms) inthe cCTG, or reverse atrial flow in the DV Doppler. Spontaneous FHR deceleration is an ominous sign, normallypreceded by the other two signs, and thus it is rarely observed, but if persistent it may justify emergency cesareansection. cCTG and DV are associated with very high risksof stillbirth within the next 3â7 days and disability. Deliver after 26 weeks by cesarean section at a tertiary carecenter under steroid treatment for lung maturation. Intact survival exceeds 50% only after 26â28 weeks, and before this threshold parents should be counseled by multidisciplinary teams. Monitoring every 12â24 h until delivery is recommended.Particularly at early gestational ages, and at whateverstage, coexistence of severe PE may distort the naturalhistory and strict fetal monitoring is warranted since fetaldeterioration may occur unexpectedly at any time.