Transition hormones are exogenous so it’s possible to emulate a cycle by varying doses (similar to the way HRT for menopause can be prescribed with oestrogen everyday plus two weeks of progesterone on and two weeks off or how the combined contraceptive pill has 21 pills followed by a 7 day break/7 days of dummy pills in order to create a ‘withdrawal bleed’) but obvs:
a) these is not the same as a natural hormonal cycle which is far more complex
b) ‘syncing’ would have to be done deliberately by timing the male human’s pseudo cycle to match the female human’s natural cycle
c) the NHS trans prescribing guidelines do not recommend prescribing any progesterone to males in transition because they don’t have wombs (prog is prescribed to menopausal women specifically for uterus health so women who have had a hysterectomy are able to do oestrogen-only HRT)
Some transitioners purchase grey market hormones from abroad or utilise private prescription services that will more or less issue prescriptions for whatever the recipient is willing to pay full price for so it is possible that your colleague’s partner is dosing themselves with a hormonal pseudo cycle, but any syncing is definitely not a natural phenomenon!
There are loads of strange menstruation myths and fantasies all over the trans-internet, some of which need copious amounts of eye bleach and some of which are bafflingly oppositional to the majority of actual female experience…
eg male transitioners often claim to have recovered an oestrogen-destroyed libido by taking large rectal doses of progesterone, whereas most women I know are angry, spotty and bloated when progesterone is at the highest monthly level thus they are far more likely to shout at you than want to shag you!
But then, progesterones/progestins can have androgenic actions so perhaps it makes sense that taking an exogenous version can raise an artificially feminised male’s libido but both natural/endogenous and synthetic or bio identical/exogenous can crash a female libido? 🤷♀️
(Of course, for the above to be true, there would have to be two biological sexes 😉)