Assessing the role of multiple pregnancies in the association between tetralogy of Fallot and assisted reproductive techniques: a path-analysis approach

Table 2 Comparison of the study population characteristics according to exposure to ART (all methods combined)

Variable		Exposure to ART				p
		No		Yes
		n	%^§	n	%^§
Mother	Age (years)
	Mean (SD)	30.4 (5.2)		33.0 (4.6)		<0.001
	Median (p25–p75)	30 (27 – 34)		33 (30 – 37)
	<20	61	1.4	0	0.0	<0.001
	20 – 29	1,874	43.4	39	22.8
	30 – 34	1,440	33.4	68	39.8
	35 – 39	727	16.9	52	30.4
	≥ 40	213	4.9	12	7.0
	Geographic origin
	France	2,416	56.4	124	72.9	<0.001
	North Africa	484	11.3	11	6.5
	Subsaharan Africa	573	13.4	9	5.3
	Other	808	18.9	26	15.3
	Occupation
	None	1,134	27.1	24	14.2	<0.001
	Professional	988	23.6	60	35.5
	Intermediate	851	20.3	43	25.4
	Administrative/public service	867	20.7	28	16.6
	Other	346	8.3	14	8.3
Father	Age (years)
	Mean (SD)	33.9 (6.6)		35.0 (5.8)		0.044
	Median (p25–p75)	33 (29 – 38)		34 (31 – 38)		0.044
	<20	6	0.2	0	0.0	<0.001
	20 – 29	924	26.1	17	10.8
	30 – 34	1,206	34.0	66	42.0
	35 – 39	756	21.3	47	29.9
	≥ 40	652	27.0	27	17.2
	Geographic origin
	France	2,327	57.1	118	71.5	0.002
	North Africa	463	11.4	11	6.7
	Subsaharan Africa	550	13.5	11	6.7
	Other	736	18.1	25	15.2
	Occupation
	None	291	7.5	6	3.7	0.023
	Professional	1,454	37.7	80	49.1
	Intermediate	573	14.9	25	15.3
	Administrative/public service	480	12.4	14	8.6
	Other	1,060	27.5	38	23.3
Pregnancy	Outcome
	Still-births	22	0.5	3	1.8	0.099
	Live-births	4,183	96.3	163	95.3
	Pregnancy terminations	123	2.8	5	2.9
	Multiplicity
	Singletons	2,908	97.0	94	71.8	<0.001
	Twins	88	2.9	31	23.7	<0.001
	Triplets	3	0.1	6	4.6

^§% calculated with the total of cases or controls without missing data as a denominator.

ISSN: 1750-1172