Table 2 Serum E₂ levels and ovarian stimulation and fertilization outcomes

Number of cycles

316

451

313

FSH during ovulation stimulation, IU/L^a

9.5 (7.5, 11.8)

8.9 (7.5, 10.6)

9 (7.7, 11)

0.098

0.047

Duration of stimulation, days^a

9 (8, 10)

8 (7, 10)*

8 (7, 9)* **

<0.001

<0.001

Gonadotropin, ampules

16 (12.5, 18)

14 (10, 18)*

14 (10.8, 17.5)*

<0.001

<0.001

E₂ at HCG day, pg/ml^a

2216 (1391, 3319)

2150.5 (1406, 3294)

2179.5 (1337.5, 3223)

0.991

0.976

Number of eggs^a

6 (3, 9)

5 (3, 8)

5 (2, 7)*

0.004

0.031

Number of mature oocytes (MII)^a

5 (3, 8)

4 (2, 7)

4 (2, 6)*

0.003

0.032

Number of embryos^a

2 (1, 4)

2 (1, 4)

2 (1, 4)

0.340

0.771

Number of good quality embryos^a

2 (1, 4)

2 (1, 3)

2 (1, 3)

0.440

0.638

Successful fertilization^b,c

1470 (82.7)

1968 (84.2)

1261 (82.9)

0.375

0.756

Successful cleavage^b,d

1432 (97.4)

1917 (97.4)

1217 (96.5)

0.257

0.995

Cancelled cycles^b

46 (14.6)

55 (12.2)

52 (16.6)

0.221

0.290 (Group B), 0.766 (Group C)