What should bpd be at 32 weeks

As a result fetal myocardial hypoxia develops. This pathophysiologic process manifests in the form of repetitive uniform late decelerations the hallmark of a positive CST. However, absence of some of these dynamic states may reflect either normal periodicity or CNS depression.

Because of these observations, Manning and associates postulated that evaluation of several fetal biophysical variables or a biophysical profile may better predict fetal health status. Subsequently, they conducted a number of studies to test the predictive ability of five biophysical variables including NST, FBM, fetal tone FT , fetal movements FM , and oligohydramnios.

Their evaluation system was simple, a score of 2 was assigned for each normal variable and 0 when the biophysical parameter was absent or abnormal. Recently, however, Manning and associates showed that the addition of the NST did not improve discriminative accuracy, when all the other four variables were normal. The outcome used for measuring true or false normal test results was fetal death within 1 week of a normal biophysical profile.

Their observed false-negative rate was 0. Overall, the results of the biophysical profile were normal, equivocal, or abnormal in The accuracy of the biophysical profile may be enhanced if guidelines to define prerequisites for the test are established. For example, to properly evaluate FBM a function governed by circadian rhythm and maternal glucose level , during the day.

Additionally, prior to testing it should be determined that the mother is not on medication known to inhibit the fetal CNS. The umbilical arteries UA and therefore Doppler interrogation of these vessels allows for the assessment of placental circulation. In the normal placenta, the resistance to passive flow decreases with increasing gestational age. However, in the growth restricted fetus, often the resistance to flow increases leading to an overall decease in flow.

It should be noted that it is the pathological conditions leading to IUGR and not fetal growth restriction itself that lead to abnormal umbilical artery Doppler values.

A number of authors have evaluated and tested the efficacy of UA Dopplers in the monitoring of the growth restricted fetus. In addition, there is continued debate regarding the implications of abnormal UA Doppler results. Unfortunately, the Doppler studies in isolation do not predict the timing of perinatal insults, and they are not able to predict which neonates will be compromised.

Therefore, this type of monitoring should be used as an adjunct to other perinatal testing. It may be used to help guide the frequency of NST or biophysical profile testing in the at risk pregnancy. Progressive decline in the flow, absent and finally reversed flow in the UA Doppler studies should prompt intensive fetal surveillance and may guide the decision to deliver when gestational age and other fetal surveillance are taken into account. In most centers management protocols list use of the NST as the initial evaluation of the fetus with altered growth.

In the event the test is nonreactive, a biophysical score is then obtained. UA Dopplers are used to determine the frequency of fetal testing, as abnormal Dopplers will prompt more frequent NSTs. Most obstetricians agree that in the face of IUGR and abnormal biophysical and bioelectric tests, intervention, regardless of pulmonary maturity, is necessary to prevent fetal death or asphyxia possibly leading to long-term CNS deficits.

By comparison the question of when to deliver an IUGR fetus, who has attained pulmonary maturity but in whom biophysical and bioelectric tests remain normal, has not been scientifically answered yet. Some physicians feel that, under these circumstances, delivery should be effected by 36—38 weeks' gestation, in the hope of preventing long-term CNS abnormalities.

Optimal diabetic antenatal care entails the early detection and appropriate management of fetal growth acceleration. The large-for-gestational age LGA neonate is at greater risk for perinatal mortality and morbidity when compared with the normal sized infant. In another study of infants weighing more than g, neonatal morbidity, neonatal mortality, and maternal morbidity were For clinical purposes, macrosomia is generally defined as a fetal weight in excess of g.

To effect improvement in perinatal care, the evolution as well as the extent or severity of macrosomia should be determined and quantified earlier in pregnancy and prior to term or attainment of maximal size and weight. Toward this end, we concur with others who believe that fetal weight above the 90th centile for gestational age is a more meaningful clinical definition of macrosomia than is absolute birth weight.

Our experience parallels that of Hadlock and associates who contend that LGA fetuses are a nonhomogeneous population with two main forms of macrosomia. On the other hand, asymmetric macrosomia occurs in diabetic patients falling into White's A—C classification. In these asymmetric LGA fetuses the head and femur measurements vary in size and length but fall below the 90th centile rank.

Fetal abdominal circumference and thigh diameter, however, both reflect soft tissue mass and may be significantly larger than normal. Fetal macrosomia is difficult to predict in the antenatal period. In the other ten fetuses AC values exceeded the upper limits of normal 2 SD above the mean for nondiabetic pregnancies between 28 and 32 weeks' gestation; delivered at term, the reliability of the macrosomia index for detection of evolving macrosomia prior to term has not been determined.

Platt and associates reported that a transverse fetal thigh diameter greater than 5. Femur length is part of the standard biometric assessment of gesational age and fetal weight. Of clinical importance, vaginal delivery was attempted in of the diabetic gravidas. The probability of cesarean delivery for disproportion in fetuses predicted to be macrosomic was Although several formulas are now available for sonographic estimation of fetal weight, to date, only two studies have evaluated the accuracy of fetal weight estimation for the detection of macrosomia.

Because of this variation, a fetus weighing g may be estimated to weigh as little as g or as much as g. Clearly, such a wide range of estimates would result in a significant number of false-negative and false-positive results. Korndorffer and associates, in a preliminary study, compared three methods for predicting macrosomia and were able to correctly diagnose only five of ten LGA fetuses by the best method.

The standard deviation of differences was These authors caution that the large standard deviations of mean differences behoves the obstetrician to use clinical judgment and centile ranks of fetal sonar parameters in addition to weight estimates when planning delivery of fetuses suspected of being macrosomic. Available methods for fetal antenatal assessment in diabetic pregnancies include biochemical urinary estriols , bioelectric antepartum fetal heart rate testing , and biophysical ultrasound modalities.

Biochemical tests, specifically serial urinary estriol determinations, have served as the standard of fetal well-being against which the value of fetal heart rate testing has been compared. Recent reports, however, have seriously questioned the value of estriol determinations as the standard. Further, the cost of serial estriols is high and there is a delay in obtaining laboratory results.

Golde and associates used bioelectric and biophysical testing to manage insulin-dependent diabetic pregnant women. Antepartum fetal heart rate testing AFHRT is, at present, the predominant approach used to assess fetal status in the insulin-dependent diabetic mother. As a result of the low false-negative rate, the contraction stress test CST has had the greatest clinical usefulness in diabetic gestations. The nonstress test NST , although widely used, has not been tested in large numbers of diabetic pregnancies.

Whittle and associates and Dooley and associates have demonstrated that NSTs are superior to estriol determinations. Dynamic ultrasound imaging provides another screening modality by allowing in utero observation of fetal activity.

Although several aspects of fetal behavior have been studied, at present, fetal breathing movements FBM and body movements FM appear to be the most promising. Natale and associates hypothesize that local excesses of carbon dioxide produced by increased glucose oxidation might stimulate fetal medullary chemosensitive areas and produce increased FBM.

Improved neonatal care has sharply reduced the incidence of neonatal deaths in IDMs. As a result attention is presently being focused on antepartum and intrapartum methods that allow for the early detection and treatment of fetal disease. In a prospective, blinded, clinical study they found that perinatal mortality consistently rose when the last test score prior to delivery fell. Whereas Of the 93 perinatal deaths, Of prognostic significance, completely normal test scores were associated with a perinatal mortality rate of 0.

Clearly, large numbers of diabetic pregnancies must be serially assessed by biophysical profile testing before its accuracy can be precisely determined. Obstet Gynecol 31, Am J Obstet Gynecol , Yerushalmy J: Relation of birth weight, gestational age, and rate of intrauterine growth to perinatal mortality.

Clin Obstet Gynecol , London, Heinemann, The pathologist's evaluation. Pediatr Clin North Am , Neurological and intellectual sequelae. Pediatrics 50, Villar J, Belizan JM: The timing factor in the pathophysiology of the intrauterine growth retardation syndrome.

J Pediatr , Rosenberg K, Grant J, Hepburn M: Antenatal detection of growth retardation-actual practice in a large maternity hospital. Br J Obstet Gynaecol 12, Scott A, Moar V, Ounsted M: The relative contributions of different maternal factors in small-for-gestational-age pregnancies.

Belizan J, Villar J, Nardin JC et al: Diagnosis of intrauterine growth retardation by a simple clinical method-measurement of uterine height. Biol Neonate , Lubchenco LO, Hansman C, Boyd E: Intrauterine growth in length and head circumference as estimated from live births at gestational ages from 26—42 weeks.

Pediatrics , J Ultrasound Med 3: 1, Am J Obstet Gynecol 35, Predictive of three fetal growth patterns leading to a closer assessment of gestational age and neonatal weight. Sabbagha RE: Intrauterine growth retardation: Antenatal diagnosis by ultrasound.

Turner G: Recognition of intrauterine growth retardation by considering comparative birth weights. Lancet 2: , Am J Obstet Gynecol 47, Campbell S, Thoms A: Ultrasound measurement of the fetal head to abdomen circumference ratio in the assessment of growth retardation.

J Ultrasound Med 3: , J Ultrasound Med 4: 65, Am J Obstet Gynecol 43, J Tenn Med Assoc , Chamberlain PF, Manning FA, Morrison I et al: Ultrasound evaluation of amniotic fluid volume: The relationship of marginal and decreased amniotic fluid volumes to perinatal outcome.

The single deepest pocket of amniotic fluid is measured vertically. If it is at least 2 cm deep, then true oligohydramnios is not considered present.

Some sonographers and clinicians find this definition too restrictive and will measure the largest pocket in two diameters. Using the AFI, the deepest pocket of fluid in each of four uterine quadrants is measured.

The four measurements are added to each other. If the sum is less than 7. If more than While these measurements are commonly used, there is considerable subjectivity involved in obtaining them.

Further, the amount of amniotic fluid present varies, depending to some extent on the state of maternal hydration. Placental Location In most cases, the exact location of the placenta is of little clinical consequence. In a few cases such as 2nd and 3rd trimester bleeding, placenta previa, low-lying placenta , the location of the placental is very important.

It is usually relatively simple to perform, readily available, and relatively inexpensive. More detailed scanning Level II, or targeted scan requires higher resolution more expensive equipment and sonographic skills that are more limited in their availablity and significantly more expensive. Indications for a Level II scan may include:. Suspicious findings on a Level I scan History of prior congenital anomaly Insulin dependent diabetes or other medical problem that increases the risk of anomaly.

History of seizure disorder, particularly if being treated with medications known to increase the risk of anomaly. As a practical matter, ultrasound scanning has proven to be so popular with patients and their obstetricians, that almost everyone receiving regular prenatal care ends up with at least one scan anyway. For this reason, the focus of the debate has more recently shifted to when and under what circumstances should patients have ultrasound scans.

Those favoring frequent, routine scans, do so on the basis that incorrect gestational age assessments can be corrected, many congenital anomalies can be detected, growth abnormalities can be identified and treated, and multiple gestations identified early, when intervention is more likely to improve results.

Those opposed to routine scanning point to the lack of significant improvement in outcome identified to date in large studies or routinely-scanned patients. The debate continues. Umbilical Cord in Cross Section Doppler Flow Studies Using the Doppler principle, blood flow through structures such as the umbilical cord can be identified and quantified. As placental resistance to flow increases, the amount of diastolic flow through the umbilical artery decreases, although systolic flow rates are usually unchanged.

As the resistance increases further, diastolic flow into the placenta ceases. In the most severe form of placental resistance, the diastolic flow reverses. Doppler flow studies can be useful in determining fetal status in the second trimester fetus who is too small for traditional fetal monitoring techniques to be useful.

Doppler can also be helpful as another measure of fetal well-being in the potentially compromised fetus with growth restriction. This information is provided by The Brookside Associates.

The opinions presented here are those of the author and do not necessarily represent the opinions of the Brookside Associates or the Department of Defense. The presence of any advertising on these pages does not constitute an endorsement of that product or service by either the US Department of Defense or the Brookside Associates. All material presented here is unclassified. Basic Ultrasound Exam In evaluating the pregnancy with ultrasound, the following observations are usually made: Number of fetuses and their position within the uterus.

Observation of the fetal heartbeat Location of the placenta Assessment of amniotic fluid volume Determination of gestational age, based on various fetal measurements screening evaluation of the fetus for gross anatomic abnormalities. Gender-specific body composition at birth has been reported, where the male infant has more fat mass and lean body mass than the female infant, especially in well-nourished mothers [ 31 ]. This phenomenon has been associated with gender-different intrauterine physical adaptations to an enhanced nutrient supply from the mother.

The male infant body composition has been more subject to maternal influences as higher pre-gestational BMI and excessive gestational weight gain [ 32 ]. Lastly, the lung maturation of the male fetus proceeds slower than in the female fetus, possibly contributing to a higher rate of low AS in the term grown fetus. In animal studies, lung fluid secretion is inhibited and the lung fluid absorption initiated by adrenalin infusions at birth [ 33 ]. And preterm asphyxiated male infants have lower adrenaline levels than female infants, again putting the boys at higher risk [ 34 ].

Whether in the term infant this will be similar is unknown. Our antenatal growth curves are unique in that all four fetal growth parameters BPD, HC, AC, and FL were measured in standardized circumstances in accordance with international guidelines [ 26 ].

GAMLSS can combine longitudinal data with a cross-sectional component and can construct centiles in a way that they are constrained and do not cross. Further, in using the GAMLSS analysis statistics, one could, by synchronizing the statistical methods of the WHO, align the biometry measurements with the neonatal and pediatric charts [ 22 , 23 ].

With the available neonatal data, we could discriminate different growth curves for boys and girls for all four fetal growth parameters and hence the EFW. Since the introduction of ultrasound in antenatal care, many reports on fetal growth curves have been published [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ]. Recognizing pathological fetal growth depends on reliable, standardized growth curves [ 35 ].

Discrepancies between the curves have often been attributed to the differences in methodology and population selection [ 36 ]. A recent report reviewed fetal growth charts, demonstrating the wide variations of methodologies on how these charts have been constructed concluding that there were many grounds for bias in the growth curves that are currently used [ 37 ].

Standardization of the methodologies with a checklist was recommended to define a high-quality study [ 37 ]. When we compare our growth charts to the requirements, these would be compliant for the combination of a high-quality control score, longitudinal design, sample size, and the fact that all four parameters BPD, HC, AC, and FL were examined Additional file 6.

All growth measurements were reviewed by certified staff members, judging all the scanned images as to whether they adhered to the protocol described. We also incorporated a strict protocol on pregnancy dating.

In Belgium, in routine obstetrical care, every pregnant woman will be offered a first, second, and third trimester ultrasound scan with fetal growth measurements. In many countries, the third trimester scan is not part of the routine care for low-risk pregnancies [ 38 ]. Furthermore, we were able to eliminate aberrant fetal growth and extreme maternal influences by excluding fetal anomalies level 1 and 2 indications and including only the mothers enrolled to a routine obstetric care scheme [ 40 ].

Finally, a population-based cohort was generated with a significant sample size over a period of 11 years. The description of a routine population could also be supported by our neonatal data. In our population selection, we further customized the charts for one maternal and one fetal factor. Other ethnicity-derived customized growth curves have arisen in response to the early reference charts from mainly Europe and the USA [ 18 , 19 ]. Ethnicity was reported to have a discriminative influence on fetal growth [ 24 , 41 ].

This highly qualitative study Additional file 6 represents a fascinating investigation of the physiology of fetal growth, concluding that optimal growth potential can be attained irrespective of the ethnicity in a selected population, which is in contradiction with the previous studies. Unfortunately, it lacks information on fetal gender differences; not all measurements were longitudinal, and the derived charts are by their selective nature manifestly not representative of a general population, regardless of the ethnicity concerned.

Our current study adds these advantages. Girls and boys both have different neonatal growth curves, assuming there is a discriminative effect of the gender on their growth trajectories. In more than three quarters of our cohort, complete neonatal data was registered, including gender registration. Therefore, we focused on developing two separate fetal growth charts, both for boys and girls.

Some limitations on constructing these charts have to be addressed. The study was performed in a university teaching hospital, a large tertiary referral center, not necessarily reflecting a routine setting. This center, on the other hand, also has a regional remit for routine obstetric care for low-risk pregnancies, but the included cases were not selected on maternal morbidity nor on parental characteristics.

Some maternal characteristics e. But artificial conception was excluded for intracytoplasmic sperm injection, since this is a level 1 ultrasound indication. Finally, it is expected that within this large time period, some women with subsequent pregnancies were included more than once for this cohort. Our fetal growth curves for the Caucasian population resemble predictive growth curves with the gender specified which can discern aberrant from normal fetal growth.

The longitudinal aspect and large cohort, covering the full trimesters, have not been reported before in the Caucasian population. The neonatal data gave us the opportunity to customize for the fetal gender. There was a marked difference between fetal boys and girls in their growth trajectory for fetal head measurements and to a lesser extent the abdominal circumferences.

Also for the estimated fetal weight, there was a difference. This gender differentiation is important in antenatal and perinatal care. Prenatal ultrasound is used not only to define fetal growth, but also gestational age. Both growth and fetal age are important in defining the time point of fetal viability and the optimization of the timing of obstetrical interventions, e.

Second trimester dating depends on fetal growth parameters and particular on the fetal head measurement. Our results suggest a gender-specific approach in counseling future parents on important issues when fetal viability starts and when is the best time point to start obstetrical interventions.

The gender differences are further demonstrated by the immediate birth outcomes for males: different anthropometry heavier, longer, and bigger heads , lower AS, and lower cord pH. Therefore, one can argue on the clinical importance of the pH findings and perhaps also the AS in our study. In summary, we present fetal growth curves with the latest statistical tools in a large, routine pregnant population with state-of-the-art ultrasound technology.

Also, the immediate neonatal outcome demonstrated gender differences favoring the girls. This could give caretakers the opportunity to take into account a gender-tailored approach in life decision care both at the margins of viability and post-term.

Investigations of abdominal masses by pulsed ultrasound. Campbell S. An improved method of fetal cephalometry by ultrasound. J Obstet Gynaecol Br Commonw. The prediction of fetal maturity by ultrasonic measurement of the biparietal diameter.

Pregnancy dating by fetal crown-rump length: a systematic review of charts. Sex differences in the prevalence of human birth defects: a population-based study. Risk factors associated with low Apgar scores in a low-income population. Paediatr Perinat Epidemiol. Male predominance in fetal distress during labor. Am J Obstet Gynecol. Article Google Scholar. Human sexual size dimorphism in early pregnancy. Am J Epidemiol. Sex differences in Apgar scores for full-term neonates.

Acta Paediatrica. Vatten LJ, Skjaerven R. Offspring sex and pregnancy outcome by length of gestation. Early Human Development. Estimation of fetal weight with the use of head, body and femur measurements — a prospective study.

Ultrasound Obstet Gynecol. Charts of fetal size: 2. Head measurements. Br J Obstet Gynaecol. Charts of fetal size: 3. Abdominal measurements. Charts of fetal size: 4. Femur length.