Table 4 Frequency of assessed parameters of twins concerning ART type.

Parameters		ART type
		IVF		IVF/ICSI		IUI
		Number	%	Number	%	Number	%
IUGR: intrauterine growth restriction; IVF: in vitro fertilization; ICSI: intracytoplasmic sperm injection; IUI: intrauterine insemination
I twin presentation	head	39	16.74	102	43.78	5	2.15
	pelvis	17	7.30	54	23.18	5	2.15
	other	3	1.29	8	3.43	0	0.00
II twin presentation	head	37	15.88	82	35.19	6	2.58
	pelvis	14	6.01	38	16.31	3	1.29
	other	8	3.43	44	18.88	1	0.43
I twin sex	male	32	13.73	84	36.05	5	2.15
	female	27	11.59	80	34.33	5	2.15
II twin sex	male	31	13.30	71	30.47	6	2.58
	female	28	12.02	93	39.91	4	1.72
Twins comorbidities	none	49	21.03	140	60.09	8	3.43
	malformations	0	0.00	6	2.58	1	0.43
	IUGR	0	0.00	1	0.43	0	0.00
	asphyxiation	4	1.72	2	0.86	1	0.43
	multiple	3	1.29	4	1.72	0	0.00
	other	3	1.29	11	4.72	0	0.00
Maturation	no	46	19.74	135	57.94	7	3.00
	yes	13	5.58	29	12.45	3	1.29
Chorionicity	dichorionic	59	25.32	145	62.23	10	4.29
	monochorionic	0	0.00	19	8.15	0	0.00
Outcome	excellent	24	10.30	80	34.33	5	2.15
	intermediate	28	12.02	63	27.04	2	0.86
	bad	7	3.00	21	9.01	3	1.29