Table 1 Participants’ baseline characteristics on menstrual cycle days 2–3

Age at inclusion (years; mean (SD))

33.9 (4.5)

34.3 (4.0)

0.581

 Age ≥ 37

45 (24.2)

53 (28.6)

0.330

 Age ≥ 40

22 (11.8)

18 (9.7)

0.515

Body mass index (kg/m²; mean (SD)) ⁑

23.1 (3.4)

23.5 (3.2)

0.103

Duration of infertility (years; median (P25, P75))

3 (2, 5)

3 (2, 5)

0.604

Types of infertility

0.882

 Primary infertility

73 (39.2)

74 (40.0)

 Secondary infertility

113 (60.8)

111 (60.0)

Primary cause of infertility:

0.651

 Tubal factor

134 (72.0)

122 (65.9)

 Male factor

26 (14.0)

25 (13.5)

 Tubal + Male factor

8 (4.3)

14 (7.6)

 Unexplained infertility

12 (6.5)

16 (8.7)

 Ovulation disturbance

3 (1.6)

2 (1.1)

 Diminished ovarian reserve

2 (1.1)

3 (1.6)

 Endometriosis

1 (0.5)

3 (1.6)

AMH (ng/ml; median (P25, P75))

2.0 (1.3, 3.0)

2.2 (1.3, 3.0)

0.558

Total AFC (median (P25, P75))

11 (8, 14)

11 (9, 14)

0.913

FSH (mIU/ml; median (P25, P75))

7.1 (6.0, 8.9)

7.1 (5.9, 8.9)

0.734

LH (mIU/ml; median (P25, P75))

4.5 (2.8, 6.1)

4.5 (2.8, 6.5)

0.806

Estradiol (pg/ml; median (P25, P75))

32.4 (25.0, 45.9)

30.7 (24.6, 40.6)

0.122