Predictive factors for oocyte retrieval failure in controlled ovarian hyperstimulation protocols: a retrospective observational cohort study

Table 2 Univariate analysis of variables in the cycles with one or more oocytes retrieved and zero oocytes retrieved

	Oocyte retrieval (+)	Oocyte retrieval (−)	P value
No. of cycles/all cycles (%)	706/744 (94.9)	38/744 (5.1)	–
Age, years	37 (23–46)^a	39 (31–46)^a	0.01
Gravida per patient, n	0 (0–7)^a	0 (0–6)^a	0.25
Parity per patient, n	0 (0–3)^a	0 (0–4)^a	0.02
BMI, kg/m²	21 (16–36)^a	21 (18–31)^a	0.42
Infertility period, years	6 (0–18)^a	7 (0–16)^a	0.09
Previous treatment cycles, n	2 (1–16)^a	2 (1–14)^a	0.87
No. of cycles with GnRH agonist long/no. of cycles (%)	190/706 (69.4)	19/38 (50.0)	0.02
No. of cycles with GnRH antagonist/no. of cycles/ (%)	216/706 (30.6)	19/38 (50.0)	0.02
Duration of hMG/rFSH, days	11 (7–21)^a	12 (8–20)^a	0.49
Dose of hMG/rFSH, IU	1425 (150–4800)^a	1500 (900–4800)^a	0.20
Hormone levels^b
FSH, mIU/ml	13.4 (3.2–113.5)^a	16.8 (7.5–43.5)^a	<0.001
LH, mIU/ml	2.3 (0.1–26.8)^a	3.8 (0.1–45.3)^a	0.006
PRL, ng/ml	30.7 (0.6–314)^a	21.3 (9.3–56.8)^a	<0.001
Estradiol, pg/ml	1717 (88–15,768)^a	633 (62–1970)^a	<0.001
Progesterone, ng/ml	0.77 (0.05–10.9)^a	0.51 (0.1–6.48)^a	0.02
Endometrial thickness^b, mm	10.9 (4.6–21.2)^a	10.3 (6.2–17.2)^a	0.51
No. of follicles over 15.5 mm^b, n	4 (1–16)^a	2 (1–6)^a	<0.001

^aMedian (range). ^bValues on the day of hCG injection. BMI: body mass index; GnRH: gonadotropin-releasing hormone; hMG: human menopausal gonadotropin; rFSH: recombinant follicle stimulating hormone; IU: international unit; LH, luteinizing hormone; PRL, prolactin; hCG: human chorionic gonadotropin