It is permissible for a woman to put henna on her hands and nails during her menstrual period and at other times. Indeed, a number of the fuqaha’ regarded it as mustahabb for a woman to dye her hands with henna at the time of her menses, because then she does not need to remove the paste for the purpose of doing wudoo’.
It was narrated from ‘Alqamah that he used to tell his womenfolk to put on henna during their menstrual period.
And it was narrated that ‘Ata’ said: It is mustahabb for a woman to dye her hands with henna when she is menstruating.
See: Musannaf Ibn ‘Ali Shaybah, 1/144
It says in Mawaahib al-Jaleel, 1/200 (which is a Maaliki book): Maalik was asked about a woman who is menstruating or junub using henna on her hands. He said: Yes, that is the time that women used to single out for that purpose, so that the dye would not be need to be removed in order to do wudoo’ for prayers. End quote.
In al-Mawsoo‘ah al-Fiqhiyyah (2/283) it says: The majority of fuqaha’ are of the view that it is permissible for a menstruating women to use henna, because it was narrated that a woman asked ‘Aa’ishah (may Allah be pleased with her) about that, saying: Can a menstruating woman dye (her hands) with henna? She said: We were with the Prophet (blessings and peace of Allah be upon him) and we used to dye our hands, and he did not tell us not to do that. And because it is narrated that the womenfolk of Ibn ‘Umar used to dye their hands with henna when they were menstruating. Ibn Rushd said: There is no difference of opinion that it is permissible for women who are menstruating or junub to dye their hands with henna, because the colour on the hands that results from it does not impede the removal of janaabah and menses by means of ghusl when she does ghusl. And there is no basis for the view that it is makrooh. End quote.
The hadeeth of ‘Aa’ishah mentioned above was narrated by Ibn Maajah (656) and classed as saheeh by al-Busayri in al-Zawaa’id and by al-Albaani in Saheeh Ibn Maajah.
To sum up: there is nothing wrong with applying henna during one’s menses, and what your husband heard is not correct. There is no basis for regarding that as makrooh, let alone haraam.
And Allah knows best.