Table 1 Demographic profile and clinical characteristics of the study subjects

Maternal age (years, mean ± SD)

34.7 ± 3.6

32.2 ± 4.8

< 0.0001 ^a

35.8 ± 3.9

29.5 ± 6.1

< 0.0001 ^a

37.2 ± 5.2

Paternal age (years, mean ± SD)

36.9 ± 5.7

33.3 ± 5.2

< 0.0001 ^a

38.3 ± 6.5

34.8 ± 4.6

0.0610

39.0 ± 6.9

Mode of egg fertilization (ICSI/non ICSI)

54/127

NA

–

30/23

NA

–

14/24

Oxygen tension (20/5%)

123/59

NA

–

16/38

NA

–

19/19

Type of embryo transfer (fresh/frozen)

128/54

NA

–

33/22

NA

–

26/13

Embryo transfer day (day 3/day 5)

110/72

NA

–

17/37

NA

–

18/20

Gestational age (weeks, mean ± SD)

39.2 ± 1.3

39.1 ± 1.2

0.4306^a

38.2 ± 3.6

38.2 ± 6.4

0.9990^a

36.5 ± 2.1

Birth weight (grams, mean ± SD)

3441.5 ± 498.6

3318.8 ± 559.3

0.0837^a

3196 ± 918.4

3411 ± 541.7

0.1324^a

2653.1 ± 576.9

Males (%)

83(45.6)

39 (50.6)

0.4972^b

26

29

0.7103^b

39(50.0)

Females (%)

99(54.4)

38 (49.4)

29

28

39(50.0)