Comparison of Naturally Conceived and IVF-DZ Twins in the Netherlands Twin Registry: A Developmental Study

Table 5

Number, mean and standard deviation (SD) for internalizing problems (int), externalizing problems (ext) and attention problems (AP) at age 3, 7, 10, and 12 years by rater (mother, father, teacher) for IVF/ICSI twins and matched NC twins.

	IVF/ICSI twins			Matched NC twins			𝑃 *
	𝑁	Mean	(SD)	𝑁	Mean	(SD)
Age 3
int mother	2808	4.73	(4.0)	2777	4.48	(3.9)	0.040
int father	2029	4.40	(3.8)	1999	4.28	(3.7)	0.408
ext mother	2799	15.86	(9.6)	2776	15.40	(9.7)	0.147
ext father	2015	14.52	(9.0)	1992	14.50	(9.3)	0.893
Age 7
int mother	1850	4.91	(4.8)	1810	4.53	(4.8)	0.048
int father	1325	3.72	(4.0)	1274	3.47	(4.1)	0.211
int teacher	1130	5.20	(5.6)	1110	4.69	(5.2)	0.039
ext mother	1879	7.11	(6.3)	1830	7.20	(6.8)	0.721
ext father	1350	6.20	(5.8)	1288	6.32	(6.2)	0.686
ext teacher	1151	4.49	(6.8)	1130	4.51	(7.0)	0.969
AP mother	1888	2.95	(2.9)	1851	2.79	(2.9)	0.126
AP father	1354	2.49	(2.6)	1291	2.42	(2.6)	0.548
AP teacher	1152	5.90	(6.7)	1131	5.51	(6.2)	0.209
Age 10
int mother	993	5.16	(5.3)	899	4.96	(5.5)	0.514
int father	697	3.51	(4.1)	617	3.72	(4.8)	0.487
int teacher	877	5.57	(5.9)	821	5.05	(5.5)	0.101
ext mother	999	6.25	(6.0)	909	6.52	(6.6)	0.427
ext father	701	4.92	(5.0)	624	5.33	(6.1)	0.271
ext teacher	898	4.85	(7.8)	834	5.13	(7.5)	0.461
AP mother	1005	2.98	(2.9)	913	2.92	(3.1)	0.678
AP father	704	2.41	(2.6)	626	2.53	(2.8)	0.490
AP teacher	900	5.81	(6.5)	836	6.07	(6.8)	0.387
Age 12
int mother	974	4.60	(5.6)	966	4.52	(5.6)	0.759
int father	690	3.57	(4.5)	658	3.59	(4.6)	0.936
int teacher	392	4.80	(5.5)	355	4.67	(5.4)	0.807
ext mother	979	5.35	(6.0)	966	5.45	(6.3)	0.792
ext father	692	4.40	(5.3)	661	4.59	(5.4)	0.617
ext teacher	400	3.91	(6.5)	360	4.61	(8.6)	0.254
AP mother	988	2.60	(2.9)	972	2.73	(3.1)	0.395
AP father	692	2.28	(2.6)	669	2.34	(2.8)	0.749
AP teacher	402	5.37	(6.2)	360	5.44	(6.5)	0.923

Note: *𝑃 value based on tests comparing IVF and matched NC groups.