I read that in a big cat article. It stated that if anything, use a serm or winstrol
here's part of it:
the progesterone receptor. It has been concluded that both nandrolone2 and several of its metabolites3,4 do indeed activate the progesterone receptor and are altered by it. On the one hand progestagenic activity decreases the estrogen receptor concentration in some tissues, it also mediates estrogenic action in other tissues5. So while estrogenic side-effects are fairly uncommon with nandrolone use alone, they can indeed occur and the implications of nandrolone's activity as a progesterone indicate these potential side-effects aren't to be solved with an aromatase inhibitor alone (like Cytadren). As long as there is estrogen in the system (indicating a possible increase of the problem when stacked with another aromatizing compound) progesterone can agonize its effects. And since progesterone receptors are found in breast tissue and have been linked to the formation of milk ducts, progestagenic activity may aggravate possibly gynocomastia. So while such problems are rare, when they occur they aren't easily treated.
It makes sense then that those particularly prone to the effects and side-effects of estrogen would take extra precaution. Blocking aromatase, considering the previous paragraph, would be a poor choice, but competitively inhibiting the estrogen receptor itself with clomiphene citrate (Clomid) or tamoxifen citrate (Nolvadex) might bring some relief since a large portion of progestagenic action is nullified if there is no circulating estrogen around, or if it is kept from being activated by the estrogen receptor. It is generally assumed that 1 mg of either every day for every 20 mg of nandrolone injected weekly is sufficient. Slightly higher doses, or the use of an aromatase inhibitor like cytadren can be stacked if nandrolone is used in conjunction with another aromatizing steroid. It has also been noted that the steroid stanozolol (Winstrol) may provide relief as it too binds to the progesterone receptor but remains unaltered by it. How strong of a competitor it is in such a case and what sort of doses would be needed are as much your guess as they are mine, so this may be non-issue. But it does bode well for the stacking of nandrolone with stanozolol in that you have nothing to lose and everything to gain.