I personally believe that this concept of women significantly decreasing in fertility after 25-30 is propaganda and a particularly modern problem.
Think about it. Society tells women to wait for marriage until at around 25-30 (to ensure careers are acquired and education finished), then the medical system will tell you that when you come out of school or establish yourself, that your fertility is rapidly, dangerously decreasing at that age and according to them, you actually become a high risk mother 35 and above, simply due to age.
What are the results? No babies at 20, no babies at 30.
Historically, Catholic women had perfectly healthy children well into their 40s.
Some women remain fertile into their 50s.
The reason why women are not as fertile nowadays or attractive is because they do not take care of themselves, letting themselves get fat, and wrinkle prematurely from not consuming enough foods with fat and collagen, those two things keep the skin tight and healthy.
Old pictures of people from the past show that men and women generally used to be more beautiful, especially those who consumed traditionally prepared foods.
Better jawlines, high cheekbones, bigger eyes, proportioned faces, this is all due to being properly nourished and not chronically inflamed from poor quality food and the stressful modern lifestyle (not enough fresh air, walking, sleep, sunshine, honouring circadian rhythms, etc.)
Men literally looked like strong, robust men at age 16. Women looked like feminine, beautiful women at 16. Now a lot of these women look like masculinized whores from birth control, and the men look like little boys in a lot of ways.
Vitamin D, for example, keeps the facial bone structures strong and defined. A lack of this is what causes the need for braces, and awkward, caved in faces (did not mean to rhyme there!)
Women who are metabolically healthy will have nourished hormones and glowing skin for a long time.
This metabolic fitness is often accomplished through healthy keto, and there have actually been women who inadvertently came out of menopause and had children, because of healthy keto.
Now I’m not saying this diet is for everyone, I am simply giving an example of what true health can look like, and often does.