[Individualized Somatic Classification of Newborns Using Birth Weight Percentiles Based On Maternal Body Height and Weight (Results of a Validation Study)]. / Individuelle somatische Klassifikation von Neugeborenen auf der Grundlage von Körperhöhe und Körpergewicht der Mutter (Ergebnisse einer Validierungsstudie).

INTRODUCTION: Birth weight is influenced by maternal anthropometry. The SGA-rate of newborns of short and light mothers (<158 cm,<53 kg) and the LGA-rate of tall and heavy mothers (>177 cm,>79 kg) are overestimated. The LGA-rate of newborns of shorter mothers and the SGA-rate of taller mothers are underestimated. Individualized birth weight percentiles (IBWP) based on 18 maternal groups (6 groups of height combined with 3 groups of weight), sex and weeks of gestation have been published. The aim of this study is to validate IBWP by evaluating SGA-, AGA-, and LGA-rates using perinatal data. METHODS: The validation study compares IBWP (1995 to 2000, n=2.2 million singletons) with percentile values from two German cohorts (i: 1995 to 2000; n=2.3 million and ii: 2007 to 2011, n=3.2 million singletons) using newborns from the Lower Saxony Perinatal Survey (n=0.56 million singleton newborns, 2001 to 2009). SGA-, AGA-, and LGA-rates were calculated using R statistical analysis. RESULTS: Common percentile charts based on the total population 1995-2000 and 2007-2011 yielded SGA-rates among shorter mothers of 21.1 to 21.6% and LGA-rates of 2.0 to 3.1%. In taller mothers, SGA-rates were 3.3 to 3.5% and LGA-rates were 26.6 to 27.1%. IBWP achieved SGA-rates of 9.0% and LGA-rates of 11.4 to 11.6% in shorter mothers and SGA- and LGA-rates of 10% in taller mothers. DISCUSSION: IBWP consider the maternal size for estimation of the fetal growth potential and achieve expected SGA- and LGA-rates of 10%. Consideration of individual growth potential avoids underestimation and overestimation of SGA- and LGA-rates. It aided analyses of birth weight with IBWP simplify the assessment of the nutritional status.

The cumulative impact of parity on the body mass index (BMI) in a non-selected Lower Saxony population.

OBJECTIVES: During the last decade obesity has been continuously rising in adults in industrial countries. The increased occurrence of perinatal complications caused by maternal obesity poses a major challenge for obstetricians during pregnancy and childbirth. This study aims to examine the association between parity, pregnancy, birth risks, and body mass index (BMI) of women from Lower Saxony, Germany. METHODS: This retrospective cohort study examined pseudonymized data of a non-selected singleton cohort from Lower Saxony's statewide quality assurance initiative. Mothers were categorized according to BMI as normal weight (18.5 to <25 kg/m2) or obese (≥30 kg/m2). RESULTS: Most of the mothers in this study population were either in their first (33.9%) or second pregnancy (43.4%). The mean age of women giving birth for the first time was 28.3 years. Maternal age increased with increasing parity. The proportion of pregnant women with a BMI over 30 was 11% in primiparous women, 14.3% in second para, 17.3% in third para and 24.1% in fourth para or more women. Increasing parity was positively correlated with the incidence of classical diseases related to obesity, namely diabetes mellitus, gestational diabetes, hypertension, pregnancy-related hypertension and urinary protein excretion. An increased risk of primary or secondary cesarean section was observed in the obese women, particularly during the first deliveries. CONCLUSIONS: There is a positive and significant correlation between parity and increased maternal BMI. The highest weight gain happens during the first pregnancy. The rate of operative deliveries and complications during delivery is increased in obese pregnant women.

Birth risks according to maternal height and weight - an analysis of the German Perinatal Survey.

Objective To investigate the variability in the prevalences of selected birth risks in women of different heights and weights. Methods Data from the German Perinatal Survey of 1998-2000 were analyzed: 503,468 cases contributed to our analysis of the prevalences of selected birth risks specified according to maternal weight groups, 502,562 cases contributed to our analysis according to maternal height groups and 43,928 cases contributed to our analysis of birth risks in women with a body mass index (BMI) of 21-23 kg/m2 but different heights and weights. Data analysis was performed using SPSS version 22. Results Some birth risks varied substantially by maternal height in women with a "normal" BMI of 21-23 kg/m2: the prevalence of post-term birth increased from 8.7% in women with a height of 150 cm to 13.5% in 185 cm tall women, the prevalence of preterm birth decreased from 5.9% (150 cm tall women) to 3.1% (185 cm tall women), a pathologic cardiotocography (CTG) or poor fetal heart sounds on auscultation occurred in 19.4% of the 150 cm tall women but only in 9.2% of 185 cm tall women and cephalopelvic disproportion decreased from 12.3% (150 cm tall women) to 1.2% (185 cm tall women). Analyses of women in different body height and weight groups (without restriction of BMI) likewise showed differences in the prevalences of some birth risks. Conclusion Birth risks may vary by height and weight in women with the same, "normal" BMI. BMI should not be the only way by which the impact of maternal height and weight is assessed with regard to perinatal outcomes such as birth risks.

The relationship between maternal age, body mass index, and the rate of preterm birth

Objective: The aim of the present study was to assess the influence of maternal age and maternal body mass index of early pregnancy on the risk of preterm delivery. Material and Methods: The study included 2.1 million liveborn single newborns with documented data at perinatal surveys. Statistical analyses were performed using the SPSS statistics program. Results: The risk of preterm births increased in obese women and in women with advanced age. Conclusion: Strategies should be developed to reduce preconceptional body mass index, and guidelines are required to help advise women who postponed childbearing.

Somatic development at birth as influenced by maternal characteristics - an analysis of the German Perinatal Survey.

We investigated the effects of maternal age, body weight, body height, weight gain during pregnancy, smoking during pregnancy, previous live births and being a single mother on somatic development at birth. We analysed data from the German Perinatal Survey for the years 1998-2000 from eight German federal states. We had available data on 508,926 singleton pregnancies and neonates in total; for 508,893 of which we could classify the neonates as small, appropriate or large for gestational age (SGA, AGA or LGA) based on the 10th and 90th birth weight percentiles. Multivariable regression analyses found statistically significant effects of a clinically relevant magnitude for smoking during pregnancy [odds ratio (OR) 2.9 for SGA births for women smoking >10 cigarettes per day], maternal height (OR 1.4 for SGA births for women <162 cm; OR 1.4 for LGA births for women >172 cm), maternal weight (OR 1.5 for SGA births for women <59 kg; OR 1.9 for LGA births for women >69 kg), weight gain during pregnancy (OR 1.9 for SGA births for women with a weight gain <8 kg; OR 2.0 for LGA births for women with a weight gain >18 kg) and previous live births (OR 2.1 for LGA births for women with one or more previous live births). Maternal age and being a single mother also had significant effects but their magnitude was small. Our analysis confirms the clinically relevant effects of smoking, maternal anthropometric measures and weight gain during pregnancy on neonatal somatic development.