1 Samuel 21:6 ESV
And David answered the priest, “Truly women have been kept from us as
always when I go on an expedition. The vessels of the young men are holy
even when it is an ordinary journey. How much more today will their vessels be holy?”

* * *

As we know that men have urges and needs, and drafting is sometimes
done in haste, and young men immediately sent from their bedrooms
and their wives, girlfriends, mistresses or prostitutes to the front lines
in mass waves ... It is interesting that king David of the Biblical kingdom
of Israel had this requirement when setting on a military campaign:
that men be abstinent from touching women.

Russian translation is similar:
И отвечал Давид священнику и сказал ему: женщин при нас не было
ни вчера, ни третьего дня, со времени, как я вышел, и сосуды отроков
чисты, а если дорога нечиста, то [хлеб] останется чистым в сосудах.
(1 Samuel 21:6).

This especially emphasises not approaching a woman in her montly
"flow" of blood (uncleanness).

Leviticus 15:19
And if a woman have an issue, and her issue in her flesh be blood, she shall
be put apart seven days: and whosoever toucheth her shall be unclean until
the even.

Russian:
Если женщина имеет истечение крови, текущей из тела ее, то она
должна сидеть семь дней во время очищения своего, и всякий, кто
прикоснется к ней, нечист будет до вечера;

Normally, the apostles required only four things from Gentiles who
accepted faith:

Acts 15:20
But that we write unto them, that they abstain from pollutions of idols, and
from fornication, and from things strangled, and from blood.

This doesn't put Christians under the Law of Moses and all the ritual
ceremonies which are impractical today without Temple or animal
sacrifice (and our sufficient sacrifice is the Lamb of God).
But I am certain about the monthly female uncleanness and I suspect
that eating or drinking blood is also forbidden to Christians too
(whether fresh or in sausages).

Leviticus 19:26
"Do not eat meat that has not been drained of its blood. "Do not practice
fortune-telling or witchcraft."

Leviticus 17
12 Therefore I said unto the children of Israel, No soul of you shall eat blood,
neither shall any stranger that sojourneth among you eat blood. 13 And
whatsoever man there be of the children of Israel, OR OF THE STRANGERS
that sojourn among you, which hunteth and catcheth any beast or fowl that
may be eaten; he shall even pour out the blood thereof, and cover it with
dust.
14 For it is the life of all flesh; the blood of it is for the life thereof: therefore I
said unto the children of Israel, Ye shall eat the blood of no manner of flesh:
for the life of all flesh is the blood thereof: whosoever eateth it shall be cut
off.

The STRANGERS that were forbidden from eating anything with blood
were Gentiles.

If you have eaten i.e. pork blood sausages, or anything with animal
blood, or have had been intimate with a woman, girl, mistress or
a prostitute in her monthly flow of unclean blood, you might have
experienced that it is not right.

But you do not have to go to Hell, you can ask forgiveness, as
the High Priest atones for the sins done in ignorance (Hebrews 9:7)
and not willful. And our High Priest is Lord Jesus Christ.

You might say, "Yes, but we are in the New Testament!"
OK, then go and sing to the lions! If you do not want to turn
the other cheek until the jaws snap, then if you render the Old
Testament "eye for an eye" justice, then you should be
aware of the need to avoid idols and witchcraft, strangled and
what the beast had slain, fornication and defiling yourself with blood
(eating or in intimate relationship).

There were talks of the soldiers who went to fight for freedoms,
but local prostitutes did not give them any discount on behalf of
that and they "remained with them" until they either repented,
or they died, maybe even to the Judgment Day, God only knows.

War is evil, sending unprivileged boys who did not have the money
to go to Switzerland where the children of oligarchs at war have
luxury parties together with plenty of expensive caviar, food and drinks,
prostitutes and all kinds of drugs and stimulants.

But we can look only to minimise the damage that is already done.

A fratricidal war is not a just war, but it is not profitable to stay
with the last girlfriend or wife who will quickly remarry (thereof
the term "black widow", for no one "returns" from an affair with her.

Ecclesiastes 7:26
And I find more bitter than death the woman, whose heart is snares and
nets, and her hands as bands: whoso pleaseth God shall escape from her;
but the sinner shall be taken by her.

in the name of the LORD God Merciful, Almighty
Amen