كليدواژه :
Head Circumference , Mean , دورسر نوزادان , risk factors , newborn
چكيده لاتين :
Neonatal head size at birth is one of the indexes of newborn well-being and with other measures like his weight and length, it could give us useful information about the quality of intrauterine growth of fetus or prenatal care of the mothers.
Objectives: The study was performed to determine the neonatal head circumference and other related factors.
Material & Methods: The type of study was cross-sectional and the sampling method was simple random. The study was performed from March 2001 until March 2002 at 4 hospitals under supervision of Tehran University of Medical Sciences. Head circumference, weight and length were measured for each newborn. Data related to maternal or neonatal characters were collected by interviewing with the mothers and examination of the newborns.
Results: There were 562 males (52.67%) and 505 females (47.33%) in the study. The mean of newbornsʹ head circumference was 34.3cm with SD=1.84cm. The mean of malesʹ head circumference (34.55) was more than the femalesʹ (34.12). Pre-term or low birth weight newborns had smaller head circumference than the other newborns (32.41 and 31.63 respectively). The mean head circumference of twins (32.22) was less than singletons (34.42). Moreover, the mothers who had vaginal delivery (34.22), and were 20 years old or less (33.96), for the first gravidity (34.13) or first parity (34.07) had newborns with lower head circumference in comparison with other mothers. There were statistical significant relations between the mean head circumference of newborn and sex (p<0.001), gestational age (p<0.0001), maternal age (p<0.03), birth weight (p<0.0001), multiple gestation (p<0.0001), type of delivery (p<0.05), Maternal gravidity (p<0.0001) and parity (p<0.0001). Furthermore, positive correlations between the newborns head circumference and gestational age (r=0.51, p<0.001), birth weight (r=0.62, p<0.001) and birth length(r-0.58, p<0.001) were found.
Conclusion: The head circumference of 3.5% of our newborns was not in the range of -SD, which means that these newborns must be examined more carefully to determine microcephaly or macrocephaly. Maternal gravidity or parity>1, male sex, singleton pregnancy, birth weight>2.5 kg, maternal age more than 35 years, gestational age>37weeks and cesarian section were significantly associated with larger head circumference. Moreover, the better the intrauterine growth of the fetus the more the newborn head circumference would be. Therefore, offering ideal situations for fetal intrauterine growth and preventing premature labor might increase the fetal head size at birth.
