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Cite this page: Hill, M.A. (2021, April 15) Embryology Birth. Retrieved from


Mark Hill (talk) 11:13, 26 March 2019 (AEDT) Removed old ICD-10 section below.

The International Classification of Diseases (ICD) has two entire chapters committed to the childbirth and the perinatal period, the major sub-headings are shown below. More detail is available on the chapter pages, Chapter XV Pregnancy Childbirth and Chapter XVI Perinatal Period. The World Health Organization's ICD classification used worldwide as the standard diagnostic tool for epidemiology, health management and clinical purposes. This includes the analysis of the general health situation of population groups. It is used to monitor the incidence and prevalence of diseases and other health problems.

Chapter XV Pregnancy, childbirth and the puerperium (O00-O99)

The codes included in this chapter are to be used for conditions related to or aggravated by the pregnancy, childbirth or by the puerperium (maternal causes or obstetric causes)

Excludes Certain diseases or injuries complicating pregnancy, childbirth and the puerperium classified elsewhere: external causes (for mortality) (V, W, X, Y); injury, poisoning and certain other consequences of external cause (S00-T88.1, , T88.6-T98); mental and behavioural disorders associated with the puerperium (F53.-); obstetrical tetanus (A34); postpartum necrosis of pituitary gland (E23.0); puerperal osteomalacia (M83.0); supervision of high-risk pregnancy (Z35.-); supervision of normal pregnancy (Z34.-).

Chapter XVI Certain conditions originating in the perinatal period (P00-P96)

Includes conditions that have their origin in the perinatal period even though death or morbidity occurs later.

Excludes congenital malformations, deformations and chromosomal abnormalities (Q00-Q99); endocrine, nutritional and metabolic diseases (E00-E90); injury, poisoning and certain other consequences of external causes (S00-T98); neoplasms (C00-D48); tetanus neonatorum (A33)

Major sub-headings are shown below, select the sub-heading link to see details.

Links: XV Pregnancy Childbirth | International Classification of Diseases - XVI Perinatal Period | International Classification of Diseases | Human Abnormal Development


Outcomes of Women Delivering at Very Advanced Maternal Age

J Womens Health (Larchmt). 2018 Jul 17. doi: 10.1089/jwh.2018.7027. [Epub ahead of print]

Arya S1, Mulla ZD1, Plavsic SK1. Author information 1 Paul L. Foster School of Medicine, Texas Tech University Health Sciences Center El Paso , El Paso, Texas. Abstract BACKGROUND: The purpose of this study was to evaluate the maternal outcome in women with very advanced maternal age (VAMA) at childbirth (>45 years) compared to advanced maternal age (35-39 and 40-44 years). METHODS: Retrospective cohort study using the Texas Public Use Data File, years 2013-2014. Maternal age was a three-level variable: 35-39 (referent), 40-44, and 45-59 years (VAMA). Adjusted risk ratios (aRRs) for the two older age groups for various obstetrical and nonobstetrical complications were calculated from log-binomial regression models. RESULTS: The sample consisted of 96,879 deliveries. In univariate analyses, a higher frequency (p < 0.05) of gestational diabetes, pregestational diabetes, chronic hypertension, pregnancy related hypertensive disorders, multiple gestation, oligohydramnios, polyhydramnios, placenta previa, postpartum hemorrhage, small for gestational age, intrauterine fetal death, and length of stay were noted in the two older maternal age groups compared to the youngest maternal age group. Multiple gestations were noted to be more frequent in the two older groups: the VAMA group had a 336% increase in their risk (aRR = 4.36, 95% CI: 3.68-5.17), while women 40-44 years of age experienced a 17% increase in their risk (aRR = 1.17, 95% CI: 1.07-1.29) compared to women in the 35-39 year group. The risk of the following outcomes was approximately doubled in VAMA women compared to the referent (all statistically significant): small for gestational age (aRR = 1.92), stillbirth (aRR = 2.12), and intrauterine fetal death (aRR = 1.96). CONCLUSIONS: This population-based study detected a dose-response association between maternal age and the risk of multiple maternal and fetal complications. KEYWORDS: advanced maternal age; fetal complications; maternal complications; very advanced maternal age PMID: 30016194 DOI: 10.1089/jwh.2018.7027


Steroid receptor coactivators 1 and 2 mediate fetal-to-maternal signaling that initiates parturition

J Clin Invest. 2015 Jul 1;125(7):2808-24. doi: 10.1172/JCI78544. Epub 2015 Jun 22.

Gao L, Rabbitt EH, Condon JC, Renthal NE, Johnston JM, Mitsche MA, Chambon P, Xu J, O'Malley BW, Mendelson CR.


The precise mechanisms that lead to parturition are incompletely defined. Surfactant protein-A (SP-A), which is secreted by fetal lungs into amniotic fluid (AF) near term, likely provides a signal for parturition; however, SP-A-deficient mice have only a relatively modest delay (~12 hours) in parturition, suggesting additional factors. Here, we evaluated the contribution of steroid receptor coactivators 1 and 2 (SRC-1 and SRC-2), which upregulate SP-A transcription, to the parturition process. As mice lacking both SRC-1 and SRC-2 die at birth due to respiratory distress, we crossed double-heterozygous males and females. Parturition was severely delayed (~38 hours) in heterozygous dams harboring SRC-1/-2-deficient embryos. These mothers exhibited decreased myometrial NF-κB activation, PGF2α, and expression of contraction-associated genes; impaired luteolysis; and elevated circulating progesterone. These manifestations also occurred in WT females bearing SRC-1/-2 double-deficient embryos, indicating that a fetal-specific defect delayed labor. SP-A, as well as the enzyme lysophosphatidylcholine acyltransferase-1 (LPCAT1), required for synthesis of surfactant dipalmitoylphosphatidylcholine, and the proinflammatory glycerophospholipid platelet-activating factor (PAF) were markedly reduced in SRC-1/-2-deficient fetal lungs near term. Injection of PAF or SP-A into AF at 17.5 days post coitum enhanced uterine NF-κB activation and contractile gene expression, promoted luteolysis, and rescued delayed parturition in SRC-1/-2-deficient embryo-bearing dams. These findings reveal that fetal lungs produce signals to initiate labor when mature and that SRC-1/-2-dependent production of SP-A and PAF is crucial for this process.

Comment in Pregnancy: Fetal signalling initiates parturition. [Nat Rev Endocrinol. 2015] Fetal-to-maternal signaling to initiate parturition. [J Clin Invest. 2015]

PMID 26098214

Pregnancy: Fetal signalling initiates parturition Nat Rev Endocrinol. 2015 Sep;11(9):505. doi: 10.1038/nrendo.2015.115. Epub 2015 Jul 7. Geach T. Comment on Steroid receptor coactivators 1 and 2 mediate fetal-to-maternal signaling that initiates parturition. [J Clin Invest. 2015] PMID 26149616


Maternal Morbidity of Women Receiving Birth Center Care in New South Wales: A Matched-Pair Analysis Using Linked Health Data

Birth. 2014 Jun 17. doi: 10.1111/birt.12114. [Epub ahead of print]

Laws PJ1, Xu F, Welsh A, Tracy SK, Sullivan EA.


BACKGROUND: Around 2 percent of women who give birth in Australia each year do so in a birth center. New South Wales, Australia's largest state, accounts for almost half of these births. Previous studies have highlighted the need for better quality data on maternal morbidity and mortality, to fully evaluate the safety of birth center care. AIMS: This study aimed to examine maternal morbidity related to birth center care for women in New South Wales. METHODS: A retrospective cohort study with matched-pairs was conducted using linked health data for New South Wales. Maternal outcomes were compared for women who intended to give birth in a birth center, matched with women who intended to give birth in the co-located hospital labor ward. RESULTS: Rates of maternal outcomes, including postpartum hemorrhage, retained placenta, and postpartum infection, were significantly lower in the birth center group, after controlling for demographic and institutional factors. Interventions such as cesarean section and episiotomy were also significantly lower in these women, and the rate of breastfeeding at discharge was higher. There existed no difference in length of stay, admission to ICU, or maternal mortality. CONCLUSIONS: Birth centers are a safe option for low-risk women; however, further research is required for some rare maternal outcomes. © 2014 Wiley Periodicals, Inc. KEYWORDS: birth center; maternal morbidity; outcomes

PMID 24935768

Elective birth at 37 weeks' gestation for women with an uncomplicated twin pregnancy

Cochrane Database Syst Rev. 2014 Feb 10;2:CD003582. [Epub ahead of print]

Dodd JM, Deussen AR, Grivell RM, Crowther CA. Author information


BACKGROUND: The optimal timing of birth for women with an otherwise uncomplicated twin pregnancy at term is uncertain, with clinical support for both elective delivery at 37 weeks, as well as expectant management (awaiting the spontaneous onset of labour). OBJECTIVES: To assess a policy of elective delivery from 37 weeks' gestation compared with an expectant approach for women with an otherwise uncomplicated twin pregnancy. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (12 December 2013). SELECTION CRITERIA: Randomised controlled trials with reported data that compared outcomes in mothers and babies who underwent elective delivery from 37 weeks' gestation in a twin pregnancy with outcomes in controls who were managed expectantly. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed trial eligibility, trial quality and extracted data from the included trials. MAIN RESULTS: Two randomised controlled trials comparing elective birth at 37 weeks for women with an uncomplicated twin pregnancy, with expectant management were included, involving 271 women and 542 infants. One trial was at an overall low risk of bias, and one trial was at unclear risk of selection bias, performance bias and detection bias.There were no statistically significant differences identified between a policy of elective birth at 37 weeks' gestation and expectant management with regards to birth by caesarean section (two studies; 271 participants; risk ratio (RR) 1.05; 95% confidence interval (CI) 0.83 to 1.32); perinatal death or serious perinatal morbidity (two studies; 542 infants; RR 0.34; 95% CI 0.01 to 8.35); or maternal death or serious maternal morbidity (one study; 235 women; RR 0.29; 95% CI 0.06 to 1.38).There were no statistically significant differences identified for the pre-specified secondary maternal and infant review outcomes reported by these two trials between the two treatment policies (including for: haemorrhage requiring blood transfusion; instrumental vaginal birth; meconium-stained liquor; Apgar score less than seven at five minutes; admission to neonatal intensive care; birthweight less than 2500 g; neonatal encephalopathy; and respiratory distress syndrome). While not a pre-specified review outcome, elective birth at 37 weeks, compared with expectant management, was shown to significantly reduce the risk of infants being born with a birthweight less than the third centile (one study; 470 infants; RR 0.30; 95% CI 0.13 to 0.68). AUTHORS' CONCLUSIONS: Early birth at 37 weeks' gestation compared with ongoing expectant management for women with an uncomplicated twin pregnancy does not appear to be associated with an increased risk of harms, findings which are consistent with the United Kingdom's National Institute for Health and Care Excellence (NICE) recommendations which advocate birth for women with a dichorionic twin pregnancy at 37 + 0 weeks' gestation. It is unlikely that sufficient clinical equipoise exists to allow for the randomisation of women to a later gestational age at birth.

PMID 24510739


Committee opinion no 579: definition of term pregnancy

Obstet Gynecol. 2013 Nov;122(5):1139-40. doi: 10.1097/01.AOG.0000437385.88715.4a.

[No authors listed]


In the past, the period from 3 weeks before until 2 weeks after the estimated date of delivery was considered "term," with the expectation that neonatal outcomes from deliveries in this interval were uniform and good. Increasingly, however, research has shown that neonatal outcomes, especially respiratory morbidity, vary depending on the timing of delivery within this 5-week gestational age range. To address this lack of uniformity, a work group was convened in late 2012, which recommended that the label "term" be replaced with the designations early term (37 0/7 weeks of gestation through 38 6/7 weeks of gestation), full term (39 0/7 weeks of gestation through 40 6/7 weeks of gestation), late term (41 0/7 weeks of gestation through 41 6/7 weeks of gestation), and postterm (42 0/7 weeks of gestation and beyond) to more accurately describe deliveries occurring at or beyond 37 0/7 weeks of gestation. The American College of Obstetricians and Gynecologists and the Society for Maternal-Fetal Medicine endorse and encourage the uniform use of the work group's recommended new gestational age designations by all clinicians, researchers, and public health officials to facilitate data reporting, delivery of quality health care, and clinical research.

PMID 24150030 [PubMed - in process]

Do parental heights influence pregnancy length?: A population-based prospective study, HUNT 2

BMC Pregnancy Childbirth. 2013 Feb 5;13:33. doi: 10.1186/1471-2393-13-33.

Myklestad K, Vatten LJ, Magnussen EB, Salvesen KÅ, Romundstad PR.

Source Department of Public Health, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim N-7489, Norway.


BACKGROUND: The objective of this study was to examine the association of maternal and paternal height with pregnancy length, and with the risk of pre- and post-term birth. In addition we aimed to study whether cardiovascular risk factors could explain possible associations. METHODS: Parents who participated in the Nord-Trøndelag Health Study (HUNT 2; 1995-1997) were linked to offspring data from the Medical Birth Registry of Norway (1997-2005). The main analyses included 3497 women who had delivered 5010 children, and 2005 men who had fathered 2798 pregnancies. All births took place after parental participation in HUNT 2. Linear regression was used to estimate crude and adjusted differences in pregnancy length according to parental heights. Logistic regression was used to estimate crude and adjusted associations of parental heights with the risk of pre- and post-term births. RESULTS: We found a gradual increase in pregnancy length by increasing maternal height, and the association was essentially unchanged after adjustment for maternal cardiovascular risk factors, parental age, offspring sex, parity, and socioeconomic measures. When estimated date of delivery was based on ultrasound, the difference between mothers in the lower height quintile (<163 cm cm) and mothers in the upper height quintile (≥ 173 cm) was 4.3 days, and when estimated date of delivery was based on last menstrual period (LMP), the difference was 2.8 days. Shorter women (< 163 cm) had lower risk of post-term births, and when estimated date of delivery was based on ultrasound they also had higher risk of pre-term births. Paternal height was not associated with pregnancy length, or with the risks of pre- and post-term births. CONCLUSIONS: Women with shorter stature had shorter pregnancy length and lower risk of post-term births than taller women, and when EDD was based on ultrasound, they also had higher risk of preterm births. The effect of maternal height was generally stronger when pregnancy length was based on second trimester ultrasound compared to last menstrual period. The association of maternal height with pregnancy length could not be explained by cardiovascular risk factors. Paternal height was neither associated with pregnancy length nor with the risk of pre- and post-term birth.

PMID 23383756


  • 40 weeks from the last normal menstrual period (LNMP).
  • 37 weeks and 42 weeks World Health Organization defines normal term.


Amniotic fluid embolism incidence, risk factors and outcomes: a review and recommendations

BMC Pregnancy Childbirth. 2012 Feb 10;12:7.

Knight M, Berg C, Brocklehurst P, Kramer M, Lewis G, Oats J, Roberts CL, Spong C, Sullivan E, van Roosmalen J, Zwart J. Source National Perinatal Epidemiology Unit, University of Oxford, Oxford, UK.


BACKGROUND: Amniotic fluid embolism (AFE) is a rare but severe complication of pregnancy. A recent systematic review highlighted apparent differences in the incidence, with studies estimating the incidence of AFE to be more than three times higher in North America than Europe. The aim of this study was to examine population-based regional or national data from five high-resource countries in order to investigate incidence, risk factors and outcomes of AFE and to investigate whether any variation identified could be ascribed to methodological differences between the studies. METHODS: We reviewed available data sources on the incidence of AFE in Australia, Canada, the Netherlands, the United Kingdom and the USA. Where information was available, the risk factors and outcomes of AFE were examined. RESULTS: The reported incidence of AFE ranged from 1.9 cases per 100 000 maternities (UK) to 6.1 per 100 000 maternities (Australia). There was a clear distinction between rates estimated using different methodologies. The lowest estimated incidence rates were obtained through validated case identification (range 1.9-2.5 cases per 100 000 maternities); rates obtained from retrospective analysis of population discharge databases were significantly higher (range 5.5-6.1 per 100 000 admissions with delivery diagnosis). Older maternal age and induction of labour were consistently associated with AFE. CONCLUSIONS: Recommendation 1: Comparisons of AFE incidence estimates should be restricted to studies using similar methodology. The recommended approaches would be either population-based database studies using additional criteria to exclude false positive cases, or tailored data collection using existing specific population-based systems.Recommendation 2: Comparisons of AFE incidence between and within countries would be facilitated by development of an agreed case definition and an agreed set of criteria to minimise inclusion of false positive cases for database studies.Recommendation 3: Groups conducting detailed population-based studies on AFE should develop an agreed strategy to allow combined analysis of data obtained using consistent methodologies in order to identify potentially modifiable risk factors.Recommendation 4: Future specific studies on AFE should aim to collect information on management and longer-term outcomes for both mothers and infants in order to guide best practice, counselling and service planning.

PMID 22325370


Methods of induction of labour: a systematic review

BMC Pregnancy Childbirth. 2011 Oct 27;11:84.

Mozurkewich EL, Chilimigras JL, Berman DR, Perni UC, Romero VC, King VJ, Keeton KL. Source Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of Michigan, 1500 E, Medical Center Drive, Ann Arbor, MI 48109-0264, USA.


BACKGROUND: Rates of labour induction are increasing. We conducted this systematic review to assess the evidence supporting use of each method of labour induction. METHODS: We listed methods of labour induction then reviewed the evidence supporting each. We searched MEDLINE and the Cochrane Library between 1980 and November 2010 using multiple terms and combinations, including labor, induced/or induction of labor, prostaglandin or prostaglandins, misoprostol, Cytotec, 16,16,-dimethylprostaglandin E2 or E2, dinoprostone; Prepidil, Cervidil, Dinoprost, Carboprost or hemabate; prostin, oxytocin, misoprostol, membrane sweeping or membrane stripping, amniotomy, balloon catheter or Foley catheter, hygroscopic dilators, laminaria, dilapan, saline injection, nipple stimulation, intercourse, acupuncture, castor oil, herbs. We performed a best evidence review of the literature supporting each method. We identified 2048 abstracts and reviewed 283 full text articles. We preferentially included high quality systematic reviews or large randomised trials. Where no such studies existed, we included the best evidence available from smaller randomised or quasi-randomised trials. RESULTS: We included 46 full text articles. We assigned a quality rating to each included article and a strength of evidence rating to each body of literature. Prostaglandin E2 (PGE2) and vaginal misoprostol were more effective than oxytocin in bringing about vaginal delivery within 24 hours but were associated with more uterine hyperstimulation. Mechanical methods reduced uterine hyperstimulation compared with PGE2 and misoprostol, but increased maternal and neonatal infectious morbidity compared with other methods. Membrane sweeping reduced post-term gestations. Most included studies were too small to evaluate risk for rare adverse outcomes. CONCLUSIONS: Research is needed to determine benefits and harms of many induction methods.

PMID 22032440

Vitamin A and E status in very low birth weight infants

J Perinatol. 2011 Jul;31(7):471-6. doi: 10.1038/jp.2010.155. Epub 2011 Jan 13.

Kositamongkol S, Suthutvoravut U, Chongviriyaphan N, Feungpean B, Nuntnarumit P. Source Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.


Objective:To determine vitamin A and vitamin E status in very low birth weight (VLBW) infants at the time of birth (TB), at the time of full feeding (TFF) and at term postmenstrual age (TT).Study Design:An observational study was conducted in VLBW infants. Plasma retinol and α-tocopherol levels were measured at TB, TFF and TT. Multivitamin supplementation was given to all infants to meet the daily requirement.Result:A total of 35 infants were enrolled. The median (interquartile range) of gestational age and birth weight was 30 (28 to 32) weeks and 1157 g (982 to 1406 g). The median of vitamin A and vitamin E intakes from TFF to TT was 832 and 5.5 IU kg(-1) day(-1), respectively. Vitamin A deficiency occurred in 67.7% at birth, 51.6% at TFF and 82.1% at TT. Vitamin E deficiency occurred in 77.4% at birth, 16.1% at TFF and 35.7% at TT. Small-for-gestational age was the only risk factor for vitamin A deficiency. Lower amount of breast milk consumption was associated with higher incidence of vitamin E deficiency. No differences in vitamin A- or vitamin E-related morbidities between infants with and without vitamin deficiencies were found.Conclusion:High prevalence of vitamin A and vitamin E deficiency was found in VLBW infants starting from birth to term postmenstrual age. Therefore, a higher dose of vitamin supplementation is required.

PMID 21233795


Choice of instruments for assisted vaginal delivery

Cochrane Database Syst Rev. 2010 Nov 10;(11):CD005455. doi: 10.1002/14651858.CD005455.pub2.

O'Mahony F1, Hofmeyr GJ, Menon V.


BACKGROUND: Instrumental or assisted vaginal birth is commonly used to expedite birth for the benefit of either mother or baby or both. It is sometimes associated with significant complications for both mother and baby. The choice of instrument may be influenced by clinical circumstances, operator choice and availability of specific instruments. OBJECTIVES: To evaluate different instruments in terms of achieving a vaginal birth and avoiding significant morbidity for mother and baby. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 May 2010). SELECTION CRITERIA: Randomised controlled trials of assisted vaginal delivery using different instruments. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial quality, extracted the data, and checked them for accuracy. MAIN RESULTS: We included 32 studies (6597 women) in this review. Forceps were less likely than the ventouse to fail to achieve a vaginal birth with the allocated instrument (risk ratio (RR) 0.65, 95% confidence interval (CI) 0.45 to 0.94). However, with forceps there was a trend to more caesarean sections, and significantly more third- or fourth-degree tears (with or without episiotomy), vaginal trauma, use of general anaesthesia, and flatus incontinence or altered continence. Facial injury was more likely with forceps (RR 5.10, 95% CI 1.12 to 23.25). Using a random-effects model because of heterogeneity between studies, there was a trend towards fewer cases of cephalhaematoma with forceps (average RR 0.64, 95% CI 0.37 to 1.11).Among different types of ventouse, the metal cup was more likely to result in a successful vaginal birth than the soft cup, with more cases of scalp injury and cephalhaematoma. The hand-held ventouse was associated with more failures than the metal ventouse, and a trend to fewer than the soft ventouse.Overall forceps or the metal cup appear to be most effective at achieving a vaginal birth, but with increased risk of maternal trauma with forceps and neonatal trauma with the metal cup. AUTHORS' CONCLUSIONS: There is a recognised place for forceps and all types of ventouse in clinical practice. The role of operator training with any choice of instrument must be emphasised. The increasing risks of failed delivery with the chosen instrument from forceps to metal cup to hand-held to soft cup vacuum, and trade-offs between risks of maternal and neonatal trauma identified in this review need to be considered when choosing an instrument.

PMID 21069686

Regulation of vascular tone and remodeling of the ductus arteriosus

J Smooth Muscle Res. 2010;46(2):77-87.

Yokoyama U, Minamisawa S, Ishikawa Y. Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine. Abstract

The ductus arteriosus (DA), a fetal arterial connection between the main pulmonary artery and the descending aorta, normally closes immediately after birth. The DA is a normal and essential fetal structure. However, it becomes abnormal if it remains patent after birth. Closure of the DA occurs in two phases: functional closure of the lumen within the first hours after birth by smooth muscle constriction, and anatomic occlusion of the lumen over the next several days due to extensive neointimal thickening in human DA. There are several events that promote the DA constriction immediately after birth: (a) an increase in arterial oxygen tension, (b) a dramatic decline in circulating prostaglandinE(2) (PGE(2)), (c) a decrease in blood pressure within the DA lumen, and (d) a decrease in the number of PGE(2) receptors in the DA wall. Anatomical closure of the DA is associated with the formation of intimal thickening, which are characterized by (a) an area of subendothelial deposition of extracellular matrix, (b) the disassembly of the internal elastic lamina and loss of elastic fiber in the medial layer, and (c) migration into the subendothelial space of undifferentiated medial smooth muscle cells. In addition to the well-known vasodilatory role of PGE(2), our findings uncovered the role of PGE(2) in anatomical closure of the DA. Chronic PGE(2)-EP4-cyclic AMP (cAMP)-protein kinase A (PKA) signaling during gestation induces vascular remodeling of the DA to promote hyaluronan-mediated intimal thickening and structural closure of the vascular lumen. A novel target of cAMP, Epac, has an acute promoting effect on smooth muscle cell migration without hyaluronan production and thus intimal thickening in the DA. Both EP4-cAMP downstream targets, Epac and PKA, regulate vascular remodeling in the DA.

PMID 20551589

Are babies getting bigger? An analysis of birthweight trends in New South Wales, 1990-2005

Hadfield RM, Lain SJ, Simpson JM, Ford JB, Raynes-Greenow CH, Morris JM, Roberts CL. Med J Aust. 2009 Mar 16;190(6):312-5. PMID: 19296812

OBJECTIVE: To determine whether the proportion of babies born large for gestational age (LGA) in New South Wales has increased, and to identify possible reasons for any increase.

DESIGN AND SETTING: Population-based study using data obtained from the NSW Midwives Data Collection, a legislated surveillance system of all births in NSW.

PARTICIPANTS: All 1 273 924 live-born singletons delivered at term (> or = 37 complete weeks' gestation) in NSW from 1990 to 2005.

MAIN OUTCOME MEASURES: LGA, defined as > 90th centile for sex and gestational age using 1991-1994 Australian centile charts; maternal factors associated with LGA were assessed using logistic regression.

RESULTS: The proportion of babies born LGA increased from 9.2% to 10.8% (18% increase) for male infants and from 9.1% to 11.0% (21% increase) for female infants. The mean birthweight increased by 23 g for boys and 25 g for girls over the study period. Increasing maternal age, higher rates of gestational diabetes and a decline in smoking contributed significantly to these increases, but did not fully explain them.

CONCLUSIONS: There is an increasing trend in the proportion of babies born LGA, which is only partly attributable to decreasing maternal smoking, increasing maternal age and increasing gestational diabetes.



Paul Portal (1630-1703), man-midwife of Paris

Arch Dis Child Fetal Neonatal Ed. 2006 Sep;91(5):F385-7.

Dunn PM. Source University of Bristol, Southmead Hospital, Southmead, Bristol BS10 5BN, UK.

Abstract Portal was the first doctor to give a good description of placenta praevia. His textbook contained interesting accounts of problem cases that he had encountered.

PMID 16923941


Invited review: Clearance of lung liquid during the perinatal period

J Appl Physiol. 2002 Oct;93(4):1542-8.

Barker PM, Olver RE.

Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina 27599-7220, USA.

Abstract At birth, the distal lung epithelium undergoes a profound phenotypic switch from secretion to absorption in the course of adaptation to air breathing. In this review, we describe the developmental regulation of key membrane transport proteins and the way in which epinephrine, oxygen, glucocorticoids, and thyroid hormones interact to bring about this crucial change in function. Evidence from molecular, transgenic, cell culture, and whole lung studies is presented, and the clinical consequences of the failure of the physiological mechanisms that underlie perinatal lung liquid absorption are discussed.

PMID 12235057

Birth lecture


Nurse - Midwifery Utah

Vaginal delivery of breech presentation.

Kotaska A, Menticoglou S, Gagnon R, Farine D, Basso M, Bos H, Delisle MF, Grabowska K, Hudon L, Mundle W, Murphy-Kaulbeck L, Ouellet A, Pressey T, Roggensack A; Maternal Fetal Medicine Committee; Society of Obstetricians and Gynaecologists of Canada. J Obstet Gynaecol Can. 2009 Jun;31(6):557-66, 567-78. English, French.

PMID 19646324


  • large size of parents (especially the mother)
  • multiparity diabetes in the mother
  • prolonged gestation
  • older maternal age
  • male infants
  • previous delivery of a high birthweight infant


from same USA report

The primary measure used to determine the gestational age of the newborn is the interval between the first day of the mother’s last normal menstrual period (LMP) and the date of birth. It is subject to error for several reasons, including imperfect maternal recall or misidentification of the LMP because of post conception bleeding, delayed ovulation, or intervening early miscarriage.

The U.S. Standard Certificate of Live Birth includes an item, ‘‘clinical/obstetric estimate of gestation,’’ that was compared with length of gestation computed from the date the last normal menstrual period (LMP) began when the latter appeared to be inconsistent with birth- weight.

USA Births: Final Data for 2006

  • In 2006, the number of births and birth and fertility rates increased for nearly all age groups, live-birth orders, race, and Hispanic origin groups and reporting areas. In some cases, rates rose to levels not seen in three or more decades.
  • A total of 4,265,555 births were registered in the United States in 2006, 3 percent higher than in 2005. This is the largest single-year increase in births since 1989 and the largest number since 1961. Births increased for all race and Hispanic origin groups between 2005 and 2006.
  • The crude birth rate for the U.S. was 14.2 live births per 1,000 persons in 2006, up slightly from 2005. The general fertility rate was 68.5 births per 1,000 women aged 15–44 years, an increase of 3 percent over 2005 and the highest rate reported since 1991. Fertility rates for nearly all race and Hispanic origin groups increased.
  • Birth rates increased for women of most age groups between 2005 and 2006. The only exceptions were the youngest mothers (under age 15 years) for whom the rate declined slightly, and mothers aged 45–49 years, for whom the birth rate was unchanged.
  • The birth rate for teenagers 15–19 years increased 3 percent in 2006, interrupting the 14-year period of continuous decline from 1991 through 2005. Only the rate for the youngest adolescents declined in 2006, to 0.6 per 1,000 aged 10–14 years. Rates for teenagers 15–17 and 18–19 years rose 3 to 4 percent each. These increases follow declines of 45 and 26 percent, respectively, in the rates between 1991 and 2005. Between 2005 and 2006, birth rates increased 3 to 5 percent each for non-Hispanic white, non- Hispanic black, and American Indian or Alaska Native teenagers and 2 percent for Hispanic teenagers. The rate for Asian or Pacific Islander teenagers was unchanged. Teenage birth rates increased significantly between 2005 and 2006 in 26 states, representing nearly every region of the country.
  • The first birth rate for women aged 15–44 years increased 3 percent to 27.4 births per 1,000 women. First birth rates increased for nearly all age groups.
  • Labor was induced for 22.5 percent of births in 2006, a slight increase over 2005, and double the rate for 1990. Induction rates are up substantially for all gestational ages, including preterm births, since 1990.
  • The cesarean delivery rate rose 3 percent to 31.1 percent of all births, another record high. The cesarean rate has climbed 50 per­ cent since the 1996 low. Rates for primary cesareans were up and vaginal births after previous cesarean were down for both revised and unrevised reporting areas. Cesarean rates have risen at all gestational ages over the last decade.
  • The preterm birth rate rose again in 2006 to 12.8 percent of all births. The percentage of infants delivered at less than 37 com­ pleted weeks of gestation has climbed 20 percent since 1990. Most of this rise is attributable to the increases in late preterm births (34–36 weeks), up 25 percent since 1990. Preterm birth rates rose slightly for Hispanic infants, but were unchanged among non-Hispanic white and non-Hispanic black infants. The singleton preterm rate also increased in 2006, to 11.1 percent. This rate has climbed 14 percent since 1990.
  • The low birthweight (LBW) rate also continued to rise, climbing to 8.3 percent in 2006, the highest level in four decades. The percentage of infants born at less than 2,500 grams has risen 19 percent since 1990. All of the rise for 2005–2006 was among moderately LBW (1,500–2,499 grams) infants. LBW rates rose slightly for Hispanic infants, but were unchanged for non-Hispanic white and non-Hispanic black infants. The LBW rate for infants born in single deliveries also increased in 2006; singleton LBW has risen 10 percent since 1990.
  • The rapid rise in multiple birth rates over the last several decades may have ended. The 2006 twin birth rate (32.1 twins per 1,000 births) remained essentially unchanged from 2005. The twin birth rate climbed 70 percent between 1980 and 2004. The triplet plus/+ birth rate declined 5 percent for 2005–2006, to 153.3 per 100,000 total births. This rate soared more than 400 percent between 1980 and 1998, but is down 21 percent since then.

Martin JA, Hamilton BE, Sutton PD, Ventura SJ, et al. Births: Final data for 2006. National vital statistics reports; vol 57 no 7. Hyattsville, MD: National Center for Health Statistics. 2009. National vital statistics reports; vol 57 no 7 PDF

Copyright information - All material appearing in this report is in the public domain and may be reproduced or copied without permission; citation as to source, however, is appreciated.

data file download

VitalStats - is a A new data access and analysis tool VitalStats

National Vital Statistics Reports [1]

VitalStats Perinatal Mortality (USA)

"Notice of Error in the 2003 and 2004 Fetal Death Data Files and Reports, and Instructions for Correcting the Data File Error

Due to a programming error, the Tabulation Flag variable located in position 9 is incorrect in the 2003 and 2004 fetal death data files. This variable identifies fetal deaths of stated or presumed period of gestation of either <20 weeks, or 20 weeks or more. Most tabulations and reports of fetal death data include only fetal deaths of 20 weeks of gestation or more. Due to this error, some fetal death records with not stated gestational ages that should have been included in the 20 weeks or more group were erroneously assigned to the <20 week group. This led to a slight underestimate of fetal mortality rates published in the National Vital Statistics Reports: Fetal and Perinatal Mortality, United States, 2003 and Fetal and Perinatal Mortality, United States, 2004. The documentation tables published in the Fetal Death User’s Guides for 2003 and 2004 are also incorrect. Tables 1 and 2 below show the effect of correcting this error on fetal and perinatal mortality rates. It should be emphasized that although the corrected rates are a bit different from those originally published, they are not statistically different in that the statements about statistical significance or lack thereof made in the fetal and perinatal reports for 2003-2005 did not change. In other words, the US fetal mortality rate did not decline significantly from 2002-03, 2003-04, 2004-05, or 2003-05. There was a significant decline in the fetal mortality rate from 2002-04 and 2002-05. In the vast majority of the states, the corrected numbers differed from the originally reported numbers by less than 1.0 percent in each year (Tables 2 and 3)."

USA Weight Gain in Pregnancy

In 1990, the Institute of Medicine (IOM) issued recommendations for gestational weight gain (43). These guidelines are based on the mother’s body mass index (BMI), which takes into account both the mother’s height and weight.

A recent workshop held by the IOM and National Academy of Sciences developed a research agenda empha­ sizing the need to make specific recommendations for subgroups such as: adolescent mothers, mothers in diverse racial and ethnic groups, and mothers carrying twins or higher order multiples (44).

2006 Data

  • 13 percent of all mothers gained less than 16 pounds (considered inadequate for most women)
  • 21 percent had weight gains of more than 40 pounds (considered excessive for all women).
  • approximately one-third of all mothers had weight gains outside of the guidelines, regardless of their height.


Maternal age and diabetes risk

  • diabetes rate for mothers 40 years of age and over was 94.3 per 1,000 (2006)
    • 6 times higher than that for mothers under 20 years of age (13.3 per 1,000).
  • Diabetes rates also differ by maternal race and ethnicity
    • highest for API mothers (7.1 percent)
    • AIAN (6.4 percent)
    • Hispanic (4.3percent) Hispanic subgroups, percent­ ages ranged from 4.0 for Cuban to 4.9 for Puerto Rican mothers.
    • non-Hispanic white (4.0percent)
    • non-Hispanic black mothers (3.7 percent)

Smoking During Pregnancy

  • overall smoking rate was 13.2 percent
    • For the 17 states for which revised information on tobacco use is available for 2006


Performance of 36 different weight estimation formulae in fetuses with macrosomia

Hoopmann M, Abele H, Wagner N, Wallwiener D, Kagan KO. Fetal Diagn Ther. 2010 Jul;27(4):204-13. Epub 2010 Jun 3.

Ultrasound estimation of fetal weight (FW) was carried out within 7 days up to delivery in 350 singleton fetuses with a birth weight (BW) of >or=4,000 g. The accuracy of the different formulae for FW estimation was compared by, firstly, the mean percentage (MPE) and mean absolute percentage error (MAPE), secondly, by the frequency distribution of differences between estimated FW and fetal BW, and thirdly by comparing detection and false positive rates in screening for fetuses with a BW of 4,000, 4,300 and 4,500 g or more.

RESULTS: MPE ranged from -62.2 to 9.6% and was closest to 0 with the Hart formula. With 12 of 36 weight estimation formulae, MAPE was 10% or less, and was smallest with the Hart formulae (3.9%). The mean detection rate among all formulae for fetuses with a BW >or=4,000, >or=4,300 and >or=4,500 g was 29, 24 and 22%, respectively, and the false positive rate was 12% (for >or=4,300 g) and 7% (>or=4,500 g).

DISCUSSION: Some formulae showed advantages as far as mean and absolute percentage errors were concerned, but none reached a detection rate and false positive rate for fetuses >or=4,500 g that could lead to clinical recommendation.

PMID 20523027

Birthdate javascript

--Mark Hill 09:58, 17 April 2012 (EST) Birthdate javascript not executable on wiki page

<script type="text/javascript" language="JavaScript">

var maxday=new Array(12) maxday[1]=31 maxday[2]=28 maxday[3]=31 maxday[4]=30 maxday[5]=31 maxday[6]=30 maxday[7]=31 maxday[8]=31 maxday[9]=30 maxday[10]=31 maxday[11]=30 maxday[12]=31

var monthname=new Array(12) monthname[1]="January" monthname[2]="February" monthname[3]="March" monthname[4]="April" monthname[5]="May" monthname[6]="June" monthname[7]="July" monthname[8]="August" monthname[9]="September" monthname[10]="October" monthname[11]="November" monthname[12]="December"

function calc(form){ var newmonth,newday,newyear day=form.Day.value year=form.Year.value month=form.Month.value newday=eval(day)+7 newmonth=eval(month)-3 newyear=eval(year) var max=maxday[month] if(month==2&&(year%4==0)){max=29}if(day>max){datestring="Wrong date, please correct and recalculate"}else{if(newday>max) {newday=newday-max newmonth=newmonth+1} if(newmonth<1){newmonth=newmonth+12}else{if(newmonth>12){newmonth=newmonth-12}newyear=newyear+1}var max=maxday[newmonth] if(newday>max){newday=newday-max newmonth=newmonth+1} var datestring=monthname[newmonth]+" "+newday+", "+newyear } form.due.value=datestring }

function today_click() {

  var theForm =;
  var nowDate = new Date();
  theForm.Day.options[nowDate.getDate() - 1].selected = true;
  theForm.Month.options[nowDate.getMonth()].selected = true;
  theForm.Year.options[nowDate.getFullYear()- 2010].selected = true;



<noscript>NOTE: You need Javascript to use the calculator, which your browser has apparently disabled.</noscript>
<form name="info">

The only information required is....
"When did your last period begin?"

<select name="Month" size="1"> <option selected value="1">January</option> <option value="2">February</option> <option value="3">March</option> <option value="4">April</option> <option value="5">May</option> <option value="6">June</option> <option value="7">July</option> <option value="8">August</option> <option value="9">September</option> <option value="10">October</option> <option value="11">November</option> <option value="12">December</option> </select><select name="Day" size="1"> <option selected value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> <option value="6">6</option> <option value="7">7</option> <option value="8">8</option> <option value="9">9</option> <option value="10">10</option> <option value="11">11</option> <option value="12">12</option> <option value="13">13</option> <option value="14">14</option> <option value="15">15</option> <option value="16">16</option> <option value="17">17</option> <option value="18">18</option> <option value="19">19</option> <option value="20">20</option> <option value="21">21</option> <option value="22">22</option> <option value="23">23</option> <option value="24">24</option> <option value="25">25</option> <option value="26">26</option> <option value="27">27</option> <option value="28">28</option> <option value="29">29</option> <option value="30">30</option> <option value="31">31</option> </select><select name="Year" size="1"> <option value="2010">2010</option> <option selected value="2011">2011</option> <option value="2012">2012</option> <option value="2013">2013</option> </select></select>
<input type="button" value="Insert today's date" onclick="today_click()" style="background-color:#ddddff">
<input type="button" value="Calculate" onclick="calc(this.form);return true;" style="background-color:#ddddff"><input type="reset" value="Reset" style="background-color:#ddddff">

Your approximate due date is:
<input type="text" size="40" name="due"></form>


Vacuum extraction versus forceps for assisted vaginal delivery

Cochrane Database Syst Rev. 2000;(2):CD000224.

Johanson RB1, Menon BK.

Update in Cochrane Database Syst Rev. 2010;(11):CD000224. PMID 21069665 (this original paper withdrawn)

Abstract BACKGROUND: Proponents of vacuum delivery argue that it should be chosen first for assisted vaginal delivery, because it is less likely to injure the mother. OBJECTIVES: The objective of this review was to assess the effects of vacuum extraction compared to forceps, on failure to achieve delivery and maternal and neonatal morbidity. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register. Date of last search: February 1999. SELECTION CRITERIA: Acceptably controlled comparisons of vacuum extraction and forceps delivery. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information. MAIN RESULTS: Ten trials were included. The trials were of reasonable quality. Use of the vacuum extractor for assisted vaginal delivery when compared to forceps delivery was associated with significantly less maternal trauma (odds ratio 0.41, 95% confidence interval 0.33 to 0.50) and with less general and regional anaesthesia. There were more deliveries with vacuum extraction (odds ratio 1.69, 95% confidence interval 1.31 to 2.19). Fewer caesarean sections were carried out in the vacuum extractor group. However the vacuum extractor was associated with an increase in neonatal cephalhaematomata and retinal haemorrhages. Serious neonatal injury was uncommon with either instrument. REVIEWER'S CONCLUSIONS: Use of the vacuum extractor rather than forceps for assisted delivery appears to reduce maternal morbidity. The reduction in cephalhaematoma and retinal haemorrhages seen with forceps may be a compensatory benefit.

PMID 10796182