Yes, it can. I've met a few Mamas on here who, like me, experienced a big dip at 9 months. For me, AF returned around that time too and that also knocked supply.
The way your breasts work changes overtime so while at the start of your BF journey it's all about producing and storing milk, lugging around great big milk boulders it then changes albeit gradually to producing more on demand, rather than storing. For me, at 9 months, it really dipped off. I could produce to feed DS (not massive amounts) but pumping became a nightmare. At 10 / 11 months I stopped expressing. I had only been expressing for the DF and when we dropped that (10m) I was just pumping for a freezer stash. But the pumping, as I say, was a nightmare. I would pump for several hours and get very little. Mamas on here told me that as time goes by, our breasts get savvier when it comes to pumping; the body isn't so easily fooled by the pump.
So. With that in mind, I think you might need to try and up supply anyway that you can. So here's a load of ideas on things you can do and things you can take. It's copied and pasted from another post so if some bits don't apply, please ignore them and forgive me for not editing? The bits I think are really REALLY important for you, I've put in bold
Things that you can do to increase your supply:*First and foremost - your lo! Nothing will stimulate your supply like your baby so key here is to nurse, nurse, and nurse some more
*Skin to skin contact - as much as you can - strip yourself off - strip lo off and climb into bed. Play, cuddle, nurse etc. Spend the whole day in bed if you can. Failing that, make sure the house is nice and warm and strip your lo off and yourself and just play like that all day. Bathing together etc... This will increase teh level of oxytocin (one of the primary milk producing hormones) and therefore help a LOT
*switch nursing: when lo has finished with the first side, offer the second. When done with the second, offer the first. When finished with the first for a second time, offer the second again. This will normally stimulate a further let down with each switch and tells your body to make more milk.*Pumping directly after the feed preferably for at least 15 mins per side although anything is better than nothing.
You can also "switch pump" which is basically going back and forth between the breasts when the milk stops coming... Pump for a few minutes even when empty, then switch back to the other breast for a letdown there again. Might be best to do this at night, after bedtime, rather than at work
Things you can consume to help:*Fenugreek, Blessed Thistle, Mothers Milk Tea & Brewers Yeast are all things you can buy at your local health food store that can be really great for helping to boost supply. With the fenugreek, it's arguably the most effective but unless you are smelling like savoury maple syrup (and I mean everything - your urine, your sweat, you!), you're not taking enough haha!
*Oatmeal/porridge. This can be great for some - I personally notice a difference with this When I've been low in the past, I've had it for breakfast and for lunch - you can also eat tons of flapjack or oatmeal cookies ~~~ porridge is great for me: porridge, milk, cinnamon, pinch of ground cloves, drop of vanilla essense and fresh berries - really helps my supply everyday. Also, oatmilk available from healthfood stores and some UK supermarkets - even do chocolate flavour
*make sure you're getting plenty of water - this really can be a major factor for many! In those early months (up to 6 months or so), I'd drink a large glass of water or milk during / or with each BF. All other drinks during the day I saw as drinks / hydration for me. *make sure you're eating properly - well balanced diet, with enough calories, enough dairy fats and health fats (such as are found in seeds and nuts etc). Up until 9 months or so, I ate an awful lot. I viewed main meals as nutrition for me, and then additional meals and snacks as feeding the boy...so I'd have breakfast and then toast an hour or so later... lots of healthy, carby nutritious snacks all day. It helped me make sure I was taking on enough to feed us both.
Hope this helps. Let me know what you think and how you get on?
Charlotte