What are the success rates of IVF with 30s vs 40s eggs?

The honest answer: IVF success with eggs from a woman in her 30s is dramatically higher than with eggs from her 40s, but the numbers depend on whether you mean her own eggs or donor eggs, and the retrieved evidence does not give you a single clean probability table for either.

The records you retrieved do not actually contain IVF success rates by maternal age. They contain fertility marker data: AMH and antral follicle count by age [1][2], and embryo chromosomal normality by age [3][4]. Those are surrogates for egg quality, not live birth rates. So I can tell you the biology, but I cannot give you the "success rate" number you asked for from these records, because the records do not report it.

What the records do show: egg quantity and quality fall steeply with age. One study of subfertile women found mean AMH of 0.69 ng/mL at age 30, dropping to 0.36 at 35 and 0.15 at 40 [2]. Embryo aneuploidy rises with age: under 35, about 44% of the best-looking embryos were chromosomally normal; at 41 and older, only about 21% were [4]. Another study found a 45% aneuploidy rate in oocytes from women averaging 38.6 years [3].

The gap between 30s and 40s is real and large, but the retrieved evidence does not give you the actual IVF live birth rate per cycle for either group. That number lives in national registry data (SART, HFEA) that was not retrieved here. My confidence is high that the age trend is steep and real, and moderate that the specific marker numbers apply to a general population, since they come from subfertile patients. The specific IVF success probability you asked for is simply not in these records.