Mazal tov on the birth of your baby!
In this case, we would recommend using spermicide. Spermicide is widely permitted halachically when contraception is allowed. In contrast, condoms are only permitted in very rare cases. Although spermicide is less effective on its own with typical use, the odds of becoming pregnant at six weeks post partum are already low, so the added protection should suffice. Furthermore, the condom is also of limited efficacy in actual use, so the additional risk with spermicide rather than a condom is not that great. Please see our article on Contraceptive Spermicides for more information, and check in with your physician with any concerns and to confirm.
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