Table 1.

Main characteristics of the sample. No significant difference was present among groups (chi-square = 4.73, p = 0.09 for trimesters/losses distribution; p > 0.05 for age and weeks differences among groups).

Previous losses	Trimesters	N	Age (mean ± SD)	Weeks (mean ± SD)
No	First	10	32.2 ± 3.0	10.9 ± 2.5
	Second	33	33.1 ± 4.5	20.0 ± 3.2
	Third	57	34.2 ± 3.9	34.2 ± 4.0
Yes	First	16	34.8 ± 3.2	9.5 ± 2.3
	Second	42	35.1 ± 3.5	21.3 ± 4.3
	Third	42	34.5 ± 3.7	34.9 ± 3.1