Figure 3. ICSI-induced [Ca²⁺]_i oscillations are unchanged with maternal age.

(a,b) Typical Ca²⁺ oscillatory patterns in young and naturally-aged eggs following ICSI. (c,d) Quantification of the number of Ca²⁺ spikes in the first hour (c) and first two hours (d) in young (n = 14) and aged (n = 10) eggs revealed no difference in oscillation frequency (P =0.61 first hour, P = 0.46 first two hours), indicating that aged eggs are capable of mounting and responding to an appropriate Ca²⁺ signal at fertilisation. (e) Quantification of fold-change fluorescence in young (n = 14) and aged (n = 10) eggs revealed the amplitude of Ca²⁺ oscillations is unaffected by age (P = 0.50). Experiments performed in Ca²⁺ -containing media. ns indicates not statistically significant. a.u. represents arbitrary units. Error bars are s.e.m.