Postnatal Birth Weight Research Articles

Effect of third trimester maternal vitamin D levels on placental weight to birth weight ratio in uncomplicated pregnancies.

Vitamin D has critical role for the fetal and placental development. Today, placental weight (PW), fetal birth weight (BW), and the PW/BW ratio are used as markers of fetal development. The aim of this study is to evaluate the relationship between vitamin D levels and these markers in uncomplicated pregnancies. This study included 108 women with uncomplicated pregnancies, defined as full-term and healthy pregnancies without perinatal complications. Vitamin D levels <12ng/mL were classified as deficient, 12-20ng/mL as insufficient, and >20ng/mL as normal. Postnatal BW and PW were compared according to maternal serum vitamin D levels. Maternal age, maternal height, maternal weight, body mass index, nulliparity, gestational age at delivery, mode of delivery, and fetal gender were similar between groups. Postnatal BW, PW, fetal height at birth, and fetal head circumference parameters were similar between the groups. The PW/BW ratio was 21.77±2.20 in the vitamin D deficient group, 21.20±2.40 in the insufficient group, and 19.98±2.37 in the normal group (p=0.012). In addition, there was a significant negative correlation between vitamin D level and the PW/BW ratio (p=0.012, r=0.031). Our results indicated that PW/BW ratio which is the marker for prediction adverse perinatal outcomes were significantly increased in the presence of vitamin D deficiency and insufficiency.

Smoking influence on early and late fetal growth.

Smoking during pregnancy is a leading and modifiable risk factor for fetal growth restriction (FGR) and low birthweight (<10th centile). We studied the effects of smoking in the development of early and late FGR or low birthweight, as well as in uteroplacental and fetoplacental hemodynamics of growth-restricted fetuses. Retrospective cohort study of 5,537 consecutive singleton pregnancies delivered at≤34+0 ("early delivery" group, n=95) and >34+0 ("late delivery" group, n=5,442) weeks of gestation. Each group was divided into smokers and non-smokers. Prenatal diagnosis of FGR was based oncustomized fetal growth standards and fetal Doppler, andpostnatal birthweight was assessed using the Olsen newborn chart. There were 15/95 (15.8%) and 602/5,442 (11.1%) smokers in the early and late delivery groups, respectively. In early deliveries, FGR was diagnosed in 3/15 (20%) of smokers and in 20/80 (25%) of non-smokers (p=0.68). We also found no differences in birthweights and hemodynamics. In late deliveres, FGR was detected in 30/602 (5%)smokers and 64/4,840 (1.3%) non-smokers (p<0.001). Birthweights <3rd centile and <10th centile were more common in smokers vs. non-smokers: 38/602 (6.3%) vs. 87/4,840 (1.8%) and 89/602 (14.8%) vs. 288/4,840 (6%), respectively (all p<0.01). Fetal Doppler of late FGR showed slightly higher umbilical artery resistances in smokers. Smoking in pregnancy is associated with FGR, low birthweight and higher umbilical artery Doppler resistances after 34weeks of gestation, but we could not confirm this association in earlier deliveries.

The relationship between umbilical cord measurements and newborn outcomes

Objective This study investigated the relationship between umbilical vein diameter and cord length and fetal outcome in low-risk pregnancies (fetuses appropriate for gestational age [AGA]). Methods A prospective cohort study of 39 singleton pregnant women aged 19–44 years at between 38+0 and 41+6 weeks of gestation was conducted. Case demographics, umbilical vein diameter measured by prenatal ultrasound, postnatal birth weight, gender, 1- and 5-minute Apgar scores, blood gas analysis, and umbilical cord length were recorded. Fetuses with a fetal weight in the 10–90th percentile according to week of gestation were accepted as AGA. Results The mean age of the pregnant women was 27.5±5.3 years. 33% (13/39) of the pregnant women were nulliparous. There was no statistically significant correlation between umbilical vein diameter and other variables in correlation analysis (p&gt;0.050). Umbilical cord length and umbilical vein lactate level were found to have a statistically negative and significant correlation (r=-0.418; p=0.015); however, no other pregnancy outcomes were found to have a significant correlation. There was no statistically significant difference between the median values of umbilical vein diameter and cord length by gender (p=0.076 and 0.181, respectively). Conclusion In conclusion, this study found no relationship between umbilical vein diameter and cord length and fetal weight and pregnancy outcome in low-risk 38.0–41.6-week pregnancies (AGA fetuses). However, the obtained results still need to be confirmed by larger series.

The effect of long term nicotine exposure on nicotine addiction and fetal growth

To investigate the effect of nicotine exposure starting before coitus and continuing during pregnancy and lactation period on delivery rate, fetal growth and nicotine addiction in rats. Ten female Swiss Albino rats were divided into 2 groups as the nicotine group (NG) (n=5), and the control group (n=5), conceived by adding 2 male rats to each group. While the control group was given only normal drinking water, 0.4 mg/kg body weight (BW)/day nicotine was given to the NG in drinking water. After delivery, the BWs of pups were recorded weekly for 6 weeks and their drinking water preferences were assessed. Meanwhile, pups of the NG continued to receive 0.4 mg/kg/day nicotine for 12 months while the controls continued with normal drinking water. At the end of the 6(th) week, it was determined that 30 (69%) rats out of 43 in the NG and only 7 rats (20%) out of 35 in the control group preferred the nicotine added drinking water (p<0.05). No significant difference was observed between control and NGs in post-natal birth weights and BWs recorded for 6 weeks. On the contrary, a significant decrease (p< 0.05) was observed in the BWs of NG at the end of 12 months nicotine exposure. Use of maternal nicotine in pregnancy and lactation periods, even at a low dose, may be effective in nicotine addiction development although it may not affect delivery rate, and BWs of pups after delivery and during six weeks follow up in the lactation period.