Table 1.

Studies of assisted hatching in unselected patients following IVF

Type of AH	No. of patients		Implantation rat (%)			Pregnancy rates (%)			Ref.
	AH	Control	AH	Control	P	AH	Control	P
PZD	15	15	25	6	<0.023	47	13	<0.05	[47]
Acid Tyrode’s	69	68	28	21	NS	54	47	NS	[15]
Acid Tyrode’s	110	108	18.9	21.9	NS	44.6	37	NS	[3]
PZD after ICSI	60	60	17.9	17.1	NS	42.1	38.1	NS	[66]
Laser	111	121	11.8	7.1	<0.05	39.6	19	<0.05	[4]
Acid Tyrode’s	13	7	9.6	10.7	NS	23	42	NS	[67]
Laser	96	103	–	–	–	30.2	29.1	NS	[68]
Laser after ICSI	51	52	17.3	20.8	NS	33.3	40.3	NS	[69]
Acid Tyrode’s after ICSI	27	25	–	–	–	44	40	NS	[11]