Reference for Pesachim 144:6

אמר רב ביבי אמר רבי אלעזר פוטר היה רבי מאיר אפי' עגל של זבחי שלמים ששחטו לשום הפסח א"ל רבי זירא לרב ביבי והאמר רבי יוחנן מודה היה רבי מאיר בבעלי מומין א"ל בבעלי מומין לא טריד בהו והאי טריד ביה

Now [according to] R. Johanan, wherein does his yebamah differ? Because he performed a religious duty! [Then in the case of] his wife too he performed a religious duty. - It refers to his wife when she is pregnant. But there is the pleasure of the periodical visit? - It was not at the time of her periodical visit. But Raba said: A man is bound to please his wife with a good deed? - It was near her [menstruation] date, If so, the same [applies to] his yebamah? - he is bashful towards his yebamah, [but] he is not bashful towards his wife.

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