Tehran University Medical Journal

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Background: The aim of the study was to investigate associations between maternal characteristics, with emphasis on hematological status, and risk of low birth weight and preterm delivery among pregnant women

Methods: In a cohort study, 1,500 pregnant women attending Hazrat Zaynab Hospital for prenatal care and delivery in the period 2000-2001, without any risk factors for preterm delivery and low birth weight were included. Maternal characteristics including hematocrit values were recorded at the first antenatal visit. Main outcome measures included birth weight and gestation at delivery. Linear and logistic regression models were used to analyze data.

Results: Severe anemia (hematocrit< 24%) was associated with a significantly increased risk of low birth weight (<2500 g) and preterm delivery (< 37 weeks gestation). High hematocrit values (> 40%) did not increase the risk of low birth weight and preterm delivery. Teenagers, women with short height or low body mass index had significantly higher risk of delivering low birth weight infants.

Conclusion.: Severe maternal anemia, particularly in the first trimester, was significantly associated with adverse pregnancy outcome. Low maternal age, height or body mass index also increased the risk of low birth weight. Improved nutritional status of young women could contribute to improved health among their infant.

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Background: Preterm labor is defined as delivery before 37 weeks of gestation. Recurrence of preterm labor in future pregnancies is 6-8%. History of preterm labor is a strong risk factor for future preterm labor. Preterm labor is the leading cause of neonatal mortality in developed countries, but permanent morbidity in these premature neonates has many side effects for the newborn as well as their family members and society. For this reason we conducted a survey to identify risk factors for recurrent preterm delivery among primiparous women with previous preterm delivery.
Methods: This prospective case–control study included patients from three university hospitals, namely Imam Khomeini, Shariati and Mirza Koochakkhan Hospitals, all in Tehran, Iran. Subjects, including 539 primiparous women who delivered preterm (22–36 weeks), were divided into two groups: 47 had a second preterm delivery (study group) and 492 had first preterm delivery (control group). Exclusion criteria were induced preterm delivery due to medical indications in mother and primigravid. Data collection and analysis was performed using SPSS 10 and t-test and χ2 test were used to analyze the significance of the results.
Results: From a total of 6,537 deliveries, we found 539 cases of preterm delivery, among which 47 cases were identified as recurrent preterm delivery. The control group was composed of 492 deliveries. The recurrence of preterm delivery was 8.7%. Uterine anomaly, cardiovascular, renal and thyroid disease in mother and blood group A had a significant correlation with recurrent preterm delivery.
Conclusion: Expectant mothers with uterine anomalies, cardiovascular, renal or thyroid diseases or group A blood type should receive extra care, observation and instructions in order to limit the risk of preterm delivery and its subsequent effects.