Pregnancy dating by lmp Dates filipines escort
accurate dating of pregnancy at times becomes difficult especially in the presence of conflicting menstrual data and patient presenting for late ultrasound, this ppt explores the ways to arrive at a correct due week or date in such a scenario do we mature early? A London-based study of over 122 000 pregnancies with spontaneous onset of labour Roshni R Patel1,2, Philip Steer3, Pat Doyle1, Mark P Little4 and Paul Elliott4 IJE vol.33 no.1 107-113 © International Epidemiological Association 2004; all rights reserved. The median gestational age at delivery was 39 weeks in Blacks and Asians and 40 weeks in white Europeans. Menstrual age Overestimates the gestational age Wilcox M et al BMJ 1993;307(6904):588-91 10-45% do not provide correct information 18% with certain dates have significant difference with USG age Geirsson et al, Br J Obstet Gynaecol. Naegeles’ rule does not correlate with actual conception date….
Meconium stained amniotic fluid, which is a sign of fetal maturity, was statistically significantly more frequent in preterm Black and Asian infants and term Black infants compared with white European infants. Baird et al498 normal cycles luteal phase 7-19 days 10% ovulate on D14 Wicox et alonly 30% of normal cycle women are fertile between 10-17 days 50% pregnancy are unintended LMP recall is error prone Indian Husbands more aware of their wives’ LMP!
Ultrasound dating RADIUS trial 1993 - 15,000 low risk women no clinical benefit to justify routine ultrasound in the absence of medical indications ACOG 2008 states that obstetricians are under no obligation to perform routine ultrasounds in low-risk women; however, it is reasonable to honor a patient's request for one.!! 1992;11-505 Doubilet , J Ultrasound Med.1993;7-653 Taipale P, Obstet Gynecol. Significant reduction in post term induction when gestational age is established by USG 1st trimester dating 70% reduction rate in post term induction Mongelli M et al Estimating the date of confinement. Predicting delivery date by ultrasound and last menstrual period in early gestation. ultrasound biometryapproximation of assumption In early pregnancy all fetuses of same age are of same size ! Convert gestational age into days21wks 1day = 148 days 8% of Margin of error (MOE) = 148 x 0.08 = 11.84 = 12 days If difference is more than MOE use USG EDD If MOE is more than difference use LMP EDD MOE is less than the difference final EDD is 10/11/03 Use always earliest USG report Subsequent USGs can be used to rule out developmental abnormalities.
The margin of error is consistently ±8% by esteemed researchers Hadlock FP, Radiology. In study of 17,000 women With reliable LMP dating post term delivery rate reduced from 10.3% to 2.7% Taipale P, Hiilesmaa V. 3rd trimester GA measurement less accurate than 2nd trimester Distal femoral epiphysis 32-33 weekssize linearly increases with GA7mm epiphysis at least 37 weeks Proximal tibial epiphysis GA at least 35 weeks Dating discrepancy Problem arises in (busy) clinical practice when significant difference exist between due date calculated by LMP and USGespecially when earlier scan is not done and patient presents late in pregnancy.
Menstrual history Indirect measure of conception of roughly 280 days Reliability depends and influenced by - recall of memory - presence of light bleeding - regularity of cycles - OCP, breast feeding etc Nichols C. Most women may round off the dates or tell preferred dates May lead to misclassification as post term pregnancy Naegeles revisited 19th century Frederiech Naegele original article in German textbook Naegele himself credits Harmann Boerhaave with Inventing the formula for EDD. Comparison of pregnancy dating by last menstrual period, ultrasound scanning and their combination. 2002;160-1666 Methods of determining the gestational age Parameter variability 2SDIVF 1 day Ovulation 3 days IUI 3 days Single I/C 4 days 1st trimester examn 2 weeks2nd trimester examn 4 weeks3rd trimester examn 6 weeks Callen PW.
Very few women actually deliver on their due date, so while it’s important to have an idea of when your baby will be born, try not to get too attached to the exact date.If you have no idea when your last period was, your doctor may order an ultrasound to determine your due date.Some women have cycles that are consistently longer than the average 28-day cycle.There are basically three ways of dividing up a pregnancy into the three trimesters; they are by: Development, Gestation, Conception.They give different dates for when the second trimester begins and for when the third trimester begins.