安全 あんぜん
an zembi

Noun

1. safe day (when unprotected sex is less likely to lead to conception)

ただし、安全 あんぜん だからって、中出 なかだししても妊娠 にんしんしないというわけではないらしいです。
tadashi anzen hidakaratte chūdashi shitemo ninshin shinaito iu wakedewa nairashiidesu.
However, it seems that just because it's a 'low risk day' doesn't mean that you won't get pregnant from intravaginal ejaculation.