Table 1 Demographic and obstetric characteristics

MATERNAL CHARACTERISTICS

  Maternal age, years [mean, SD]

30.7 [4.7]

29.2 [5.2]

  Maternal age ≥ 35 years

196 (18.0)

544 (16,9)

1.1 (0.9-1.2)

0.400

  Maternal BMI, kg/m², [mean, SD]

24.8 [5.1]

Not available

-

-

  Maternal obesity (BMI ≥ 30 kg/m²)

155 (14.3)

Not available

-

-

  Primiparity

574 (52.9)

1370 (42.7)

1.2 (1.2-1.3)

<0.001

  Daily/occasionally smoking 1.trimester

93 (8.5)

673 (21.0)

0.4 (0.3-0.5)

<0.001

  Anterior placental site

479 (44.1)

Not available

-

-

DELIVERY MODE

  Vaginal deliveries

905 (83.3)

2545 (78.3)

1.1 (1.0-1.1)

<0.001

    Induced vaginal deliveries

182 (20.1)

304 (11.9)

1.7 (1.4-2.0)

<0.001

    Assisted vaginal delivery

131 (14.5)

282 (11.1)

1.3 (1.1-1.6)

0.006

  Cesarean sections (CS), total

181 (16.7)

706 (21.6)

0.8 (0.7-0.9)

<0.001

    Emergency CS

117 (64.6)

442 (62.6)

1.0 (0.9-1.7)

0.552

CHARACTERISTICS OF THE NEWBORNS AND BIRTH OUTCOME

  Gestational age, weeks [mean,SD]

39.6 [1.6]

39.2 [1.9]

  Male gender

562 (51.7)

1726 (52.7)

1.0 (0.9-1.1)

0.588

  Birth weight in grams [mean, SD]

3584 [524]

3492 [623]

-

-

  Low birth weight (<2500gr)

27 (2.5)

147 (4.5)

0.6 (0.4-0.9)

0.006

  Stillbirth [> 22 weeks, per 1000]

3 [2.7/1000]

8 [2.4/1000]

  Preterm (22⁰-36⁶ weeks)

52 (4.8)

213 (6.6)

0.7 (0.5-1.0)

0.031

  Apgar score <7_5min

16 (1.5)

55 (1.7)

0.9 (0.5-1.5)

0.642